[sage-devel] Re: writing an interpeter for mathematica language

[David]

From a social point of view, I think this would be a great idea.
However, Mathematica contains many functions that have no equivalent
in Sage. You might find yourself re-implementing Mathematica from
scratch.

-David

On Dec 24, 5:15 pm, "Ondrej Certik" <[EMAIL PROTECTED]> wrote:
> Hi,
>
> I am thinking for a long time already of writing an interpreter, in
> Python of course, of the Mathematica
> language:
>
> http://code.google.com/p/sympy/issues/detail?id=161
>
> that would call Sage (or SymPy) as a backend to do the actual
> calculations. People would
> just take their Mathematica code, and execute it directly in Sage. So
> that they could
> use Sage immediatelly. See the issue above for some details. I quite
> like the idea of
> telling my professor - you don't have to download 450MB download and you don't
> have to steal it in order to use it from home, you can just download 200MB 
> Sage
> and use your program freely everywhere. And when people start using Sage,
> even though with Mathematica programs, I think they will just switch to Python
> with new programs.
>
> What are your thoughts - especially from the social point of view - is
> it a bad or good idea?
>
> Ondrej

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[sage-devel] Re: [fricas-devel] Clisp and graphics

[David Joyner]

Hi Bill:
Does it make sense to build an axiom4sage package which uses the
pre-installed clisp (since maxima comes with clisp) to make the
axiom graphics engine? If so, do you know how long such a package
would take to compile, on average?
- David

On 11/10/07, Waldek Hebisch <[EMAIL PROTECTED]> wrote:
>
> Some time ago I wrote that some graphic examples do not work when
> using clisp based FriCAS.  I belive that the problem is fixed now
> (in revision 123).  The problem was mostly because by default
> clisp is not Ansi compilant, in particular some operations which
> according to Ansi give double floats in fact produced integer
> result.  Fortunately, clisp has a flag which switches off most
> of noncompliant behaviour -- that fixed most of the problems.
> I also had to explicitly coerce Pi to double float (Ansi says
> that PI is of type long float, and in clisp long float is
> different than double float).
>
> So, now graphic should work in clisp based FriCAS as well as
> in gcl or sbcl based FriCAS.
>
> --
>   Waldek Hebisch
> [EMAIL PROTECTED]
>
> >
>

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[sage-devel] Re: plotQt.c with Qt 4.3.2 + GUI for pari/gp

[David Joyner]

I tried emailing the author of mathguide several times a few years ago,
with no response. Of course, my email was in English, which might have been the
problem. In any case, I did not get the impression that it was open source.
Either I am wrong or I presume this guy got permission from the
mathguide author to distribute a derived work based on his code?



On Nov 12, 2007 9:33 PM, William Stein <[EMAIL PROTECTED]> wrote:
>
> On Nov 13, 2007 1:35 AM, Téragone <[EMAIL PROTECTED]> wrote:
> > I'm also working on a GUI for pari/gp. I started with mathGuide from which I
> > removed the Python plugin
>
> Wow, thanks for pointing out mathGuide, which I had never heard about before.
> Since this is in English, I translation of the web page
>   http://www.math.uni-siegen.de/ring/mathGUIde
> is here:
> http://babelfish.altavista.com/babelfish/trurl_pagecontent?lp=de_en&url=http%3A%2F%2Fwww.math.uni-siegen.de%2Fring%2FmathGUIde%2Findex.html
>
> It's interesting how that project is fairly similar to Sage
> (http://sagemath.org)
> in many ways.  E.g., see this screenshot which looks very much like
> the screen shot for mathGUIde:
> http://sagemath.org/screen_shots/.html/sage-screenshot.png
>
> >. I call gp in application mode, not in library
> > mode.
> >  I use most of the code of gp.c and I redirect the output to a global
> > string. Maybe not the best way, but it's easy to code and it work.
>
> Interestingly the Sage GP GUI also uses GP rather than the PARI
> C library for the GUI (though Sage also uses PARI). Anyway,
> here is a screenshot from Sage that actually looks a lot like
> yours below:
>
> http://sagemath.org/screen_shots/.html/sage-pari.png
>
> > For now, my new code is source compatible only. All the modifications have
> > been include in #ifdef/#endif so the "original" gp compile and work with no
> > modification.
> > Still many hours before it will work correctly. I use Qt so it must be
> > possible to port it on many OS. I only tested it on Linux. Here a screenshot
> > :
> >
> > http://pages.videotron.com/teragone/gui.png
> >
> > Please, let me know if you have interest for that.
>
> I'm excited that there is so much enthusiasm and energy for open source
> projects / guis, etc., related to mathematical software right now.   I wonder
> if you've solved any problems I don't know how to solve (and conversely)
> related to such things?
>
>   -- William
>
> >
>

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[sage-devel] Re: plotQt.c with Qt 4.3.2 + GUI for pari/gp

[David Joyner]

On 11/13/07, Fabio Tonti <[EMAIL PROTECTED]> wrote:
> The original Webpage says "[mathGUIde] ist Freeware und wird mit allen
> Quellen verbreitet" which means that "it's freeware and is distributed with
> all the sources".
> So it doesn't state any licensing details e.g. whether you may modify the
> source etc.
> Maybe I should download it and look into the sourcefiles? There could be
> some hidden licensing information.

Please do. I did and didn't find anything. But everything is in German,
so my search wasn't very useful if there is some information in with other
things. Might be worth emailing Ring. If it is opensource then perhaps
it could be
adapted to be used as a windows SAGE gui interface?


>
> Fabio
>
>
> On Nov 13, 2007 3:53 AM, William Stein < [EMAIL PROTECTED]> wrote:
> >
> >
> > On Nov 13, 2007 2:50 AM, David Joyner <[EMAIL PROTECTED]> wrote:
> > > I tried emailing the author of mathguide several times a few years ago,
> > > with no response. Of course, my email was in English, which might have
> been the
> > > problem. In any case, I did not get the impression that it was open
> source.
> > > Either I am wrong or I presume this guy got permission from the
> > > mathguide author to distribute a derived work based on his code?
> >
> > It's probably open source I guess, since the web page says
> > (translated) "Freeware is and with all sources is spread".  Perhaps a
> > German speaker could look at
> >
> >   http://www.math.uni-siegen.de/ring/mathGUIde
> > and confirm this.
> >
> > William
> >
> >
> >
> >
> > >
> > > 
> > >
> > >
> > > On Nov 12, 2007 9:33 PM, William Stein <[EMAIL PROTECTED]> wrote:
> > > >
> > > > On Nov 13, 2007 1:35 AM, Téragone < [EMAIL PROTECTED]> wrote:
> > > > > I'm also working on a GUI for pari/gp. I started with mathGuide from
> which I
> > > > > removed the Python plugin
> > > >
> > > > Wow, thanks for pointing out mathGuide, which I had never heard about
> before.
> > > > Since this is in English, I translation of the web page
> > > >   http://www.math.uni-siegen.de/ring/mathGUIde
> > > > is here:
> > > >
> http://babelfish.altavista.com/babelfish/trurl_pagecontent?lp=de_en&url=http%3A%2F%2Fwww.math.uni-siegen.de%2Fring%2FmathGUIde%2Findex.html
> > > >
> > > > It's interesting how that project is fairly similar to Sage
> > > > (http://sagemath.org)
> > > > in many ways.  E.g., see this screenshot which looks very much like
> > > > the screen shot for mathGUIde:
> > > >
> http://sagemath.org/screen_shots/.html/sage-screenshot.png
> > > >
> > > > >. I call gp in application mode, not in library
> > > > > mode.
> > > > >  I use most of the code of gp.c and I redirect the output to a
> global
> > > > > string. Maybe not the best way, but it's easy to code and it work.
> > > >
> > > > Interestingly the Sage GP GUI also uses GP rather than the PARI
> > > > C library for the GUI (though Sage also uses PARI). Anyway,
> > > > here is a screenshot from Sage that actually looks a lot like
> > > > yours below:
> > > >
> > > >
> http://sagemath.org/screen_shots/.html/sage-pari.png
> > > >
> > > > > For now, my new code is source compatible only. All the
> modifications have
> > > > > been include in #ifdef/#endif so the "original" gp compile and work
> with no
> > > > > modification.
> > > > > Still many hours before it will work correctly. I use Qt so it must
> be
> > > > > possible to port it on many OS. I only tested it on Linux. Here a
> screenshot
> > > > > :
> > > > >
> > > > > http://pages.videotron.com/teragone/gui.png
> > > > >
> > > > > Please, let me know if you have interest for that.
> > > >
> > > > I'm excited that there is so much enthusiasm and energy for open
> source
> > > > projects / guis, etc., related to mathematical software right now.   I
> wonder
> > > > if you've solved any problems I don't know how to solve (and
> conversely)
> > > > related to such things?
> > > >
> > > >   -- William
> > > >
> > > > >
> > > >
> > >
> > > >
> > >
> >
> >
> >
> > --
> > William Stein
> > Associate Professor of Mathematics
> > University of Washington
> > http://wstein.org
> >
> >
> >
> >
> >
>
>
>  >
>

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[sage-devel] Re: plotQt.c with Qt 4.3.2 + GUI for pari/gp

[David Joyner]

Please do!


On 11/13/07, Fabio Tonti <[EMAIL PROTECTED]> wrote:
> I couldn't find anything either. It only states
>
> >># mathguide Version 1.0 -- 2006-04-05
>
> >># Copyright 2004-2006 Hartmut Ring
>
> which doesn't sound that good. Mailing ring sounds like a good idea. Should
> I do it?
>
>
>
>
> On Nov 13, 2007 12:41 PM, David Joyner <[EMAIL PROTECTED]> wrote:
>
> >
> > On 11/13/07, Fabio Tonti <[EMAIL PROTECTED]> wrote:
> > > The original Webpage says "[mathGUIde] ist Freeware und wird mit allen
> > > Quellen verbreitet" which means that "it's freeware and is distributed
> > with
> > > all the sources".
> > > So it doesn't state any licensing details e.g. whether you may modify
> > the
> > > source etc.
> > > Maybe I should download it and look into the sourcefiles? There could be
> > > some hidden licensing information.
> >
> > Please do. I did and didn't find anything. But everything is in German,
> > so my search wasn't very useful if there is some information in with other
> > things. Might be worth emailing Ring. If it is opensource then perhaps
> > it could be
> > adapted to be used as a windows SAGE gui interface?
> >
> >
> > >
> > > Fabio
> > >
> > >
> > > On Nov 13, 2007 3:53 AM, William Stein < [EMAIL PROTECTED]> wrote:
> > > >
> > > >
> > > > On Nov 13, 2007 2:50 AM, David Joyner <[EMAIL PROTECTED]> wrote:
> > > > > I tried emailing the author of mathguide several times a few years
> > ago,
> > > > > with no response. Of course, my email was in English, which might
> > have
> > > been the
> > > > > problem. In any case, I did not get the impression that it was open
> > > source.
> > > > > Either I am wrong or I presume this guy got permission from the
> > > > > mathguide author to distribute a derived work based on his code?
> > > >
> > > > It's probably open source I guess, since the web page says
> > > > (translated) "Freeware is and with all sources is spread".  Perhaps a
> > > > German speaker could look at
> > > >
> > > >   http://www.math.uni-siegen.de/ring/mathGUIde
> > > > and confirm this.
> > > >
> > > > William
> > > >
> > > >
> > > >
> > > >
> > > > >
> > > > > 
> > > > >
> > > > >
> > > > > On Nov 12, 2007 9:33 PM, William Stein <[EMAIL PROTECTED]> wrote:
> > > > > >
> > > > > > On Nov 13, 2007 1:35 AM, Téragone < [EMAIL PROTECTED]> wrote:
> > > > > > > I'm also working on a GUI for pari/gp. I started with mathGuide
> > from
> > > which I
> > > > > > > removed the Python plugin
> > > > > >
> > > > > > Wow, thanks for pointing out mathGuide, which I had never heard
> > about
> > > before.
> > > > > > Since this is in English, I translation of the web page
> > > > > >   http://www.math.uni-siegen.de/ring/mathGUIde
> > > > > > is here:
> > > > > >
> > >
> >
> http://babelfish.altavista.com/babelfish/trurl_pagecontent?lp=de_en&url=http%3A%2F%2Fwww.math.uni-siegen.de%2Fring%2FmathGUIde%2Findex.html
> > > > > >
> > > > > > It's interesting how that project is fairly similar to Sage
> > > > > > (http://sagemath.org)
> > > > > > in many ways.  E.g., see this screenshot which looks very much
> > like
> > > > > > the screen shot for mathGUIde:
> > > > > >
> > > http://sagemath.org/screen_shots/.html/sage-screenshot.png
> > > > > >
> > > > > > >. I call gp in application mode, not in library
> > > > > > > mode.
> > > > > > >  I use most of the code of gp.c and I redirect the output to a
> > > global
> > > > > > > string. Maybe not the best way, but it's easy to code and it
> > work.
> > > > > >
> > > > > > Interestingly the Sage GP GUI also uses GP rather than the PARI
> > > > > > C library for the GUI (though Sage also uses PARI). Anyway,
> > > > > > here is a screenshot from

[sage-devel] Re: [SAGEdev] Error building sage in Solaris 10 with gcc 4.0.2

[David Joyner]

Klas:
Thanks for your report but it was sent to the wrong list.
(The sf list is "closed". I'm forwarding this to the correct list.)
- David Joyner

On Nov 14, 2007 8:19 AM, Klas Heggemann <[EMAIL PROTECTED]> wrote:
>
>  This fails in the building of one of the libraries:
>
>  SunOS sgray.nada.kth.se 5.10 Generic_127111-02 sun4u sparc
> SUNW,Sun-Fire-280R
>  
>  
>  GCC Version
>  gcc -v
>  Using built-in specs.
>  Target: sparc-sun-solaris2.10
>  Configured with: ../gcc-4.0.2/configure --prefix=/pkg/gcc/4.0.2/os
>  Thread model: posix
>  gcc version 4.0.2
>  
>  make[2]: Entering directory
> `/afs/.nada.kth.se/pkg/sage/src/sage-2.8.12/spkg/build/flint-0.2.p4/src'
>  gcc -std=c99 -I/afs/.nada.kth.se/pkg/sage/src/sage-2.8.12/local/include/
> -I/afs/.nada.kth.se/pkg/sage/src/sage-2.8.12/local/include
> -fexpensive-optimizations  -fPIC -funroll-loops   -O3 -c mpn_extras.c -o
> mpn_extras.o
>  gcc -std=c99 -I/afs/.nada.kth.se/pkg/sage/src/sage-2.8.12/local/include/
> -I/afs/.nada.kth.se/pkg/sage/src/sage-2.8.12/local/include
> -fexpensive-optimizations  -fPIC -funroll-loops   -O3 -c Z.c -o Z.o
>  gcc -std=c99 -I/afs/.nada.kth.se/pkg/sage/src/sage-2.8.12/local/include/
> -I/afs/.nada.kth.se/pkg/sage/src/sage-2.8.12/local/include
> -fexpensive-optimizations  -fPIC -funroll-loops   -O3 -c memory-manager.c -o
> memory-manager.o
>  gcc -std=c99 -I/afs/.nada.kth.se/pkg/sage/src/sage-2.8.12/local/include/
> -I/afs/.nada.kth.se/pkg/sage/src/sage-2.8.12/local/include
> -fexpensive-optimizations  -fPIC -funroll-loops   -O3 -c Z_mpn.c -o Z_mpn.o
>  gcc -std=c99 -I/afs/.nada.kth.se/pkg/sage/src/sage-2.8.12/local/include/
> -I/afs/.nada.kth.se/pkg/sage/src/sage-2.8.12/local/include
> -fexpensive-optimizations  -fPIC -funroll-loops   -O3 -c ZmodF.c -o ZmodF.o
>  gcc -std=c99 -I/afs/.nada.kth.se/pkg/sage/src/sage-2.8.12/local/include/
> -I/afs/.nada.kth.se/pkg/sage/src/sage-2.8.12/local/include
> -fexpensive-optimizations  -fPIC -funroll-loops   -O3 -c ZmodF_mul.c -o
> ZmodF_mul.o
>  gcc -std=c99 -I/afs/.nada.kth.se/pkg/sage/src/sage-2.8.12/local/include/
> -I/afs/.nada.kth.se/pkg/sage/src/sage-2.8.12/local/include
> -fexpensive-optimizations  -fPIC -funroll-loops   -O3 -c ZmodF_mul-tuning.c
> -o ZmodF_mul-tuning.o
>  gcc -std=c99 -I/afs/.nada.kth.se/pkg/sage/src/sage-2.8.12/local/include/
> -I/afs/.nada.kth.se/pkg/sage/src/sage-2.8.12/local/include
> -fexpensive-optimizations  -fPIC -funroll-loops   -O3 -c fmpz.c -o fmpz.o
>  gcc -std=c99 -I/afs/.nada.kth.se/pkg/sage/src/sage-2.8.12/local/include/
> -I/afs/.nada.kth.se/pkg/sage/src/sage-2.8.12/local/include
> -fexpensive-optimizations  -fPIC -funroll-loops   -O3 -c fmpz_poly.c -o
> fmpz_poly.o
>  gcc -std=c99 -I/afs/.nada.kth.se/pkg/sage/src/sage-2.8.12/local/include/
> -I/afs/.nada.kth.se/pkg/sage/src/sage-2.8.12/local/include
> -fexpensive-optimizations  -fPIC -funroll-loops   -O3 -c mpz_poly-tuning.c
> -o mpz_poly-tuning.o
>  gcc -std=c99 -I/afs/.nada.kth.se/pkg/sage/src/sage-2.8.12/local/include/
> -I/afs/.nada.kth.se/pkg/sage/src/sage-2.8.12/local/include
> -fexpensive-optimizations  -fPIC -funroll-loops   -O3 -c mpz_poly.c -o
> mpz_poly.o
>  gcc -std=c99 -I/afs/.nada.kth.se/pkg/sage/src/sage-2.8.12/local/include/
> -I/afs/.nada.kth.se/pkg/sage/src/sage-2.8.12/local/include
> -fexpensive-optimizations  -fPIC -funroll-loops   -O3 -c ZmodF_poly.c -o
> ZmodF_poly.o
>  ZmodF_poly.c: In function 'ZmodF_poly_bit_pack_mpn':
>  ZmodF_poly.c:217: error: 'u_int16_t' undeclared (first use in this
> function)
>  ZmodF_poly.c:217: error: (Each undeclared identifier is reported only once
>  ZmodF_poly.c:217: error: for each function it appears in.)
>  ZmodF_poly.c:217: error: syntax error before 'lower'
>  ZmodF_poly.c:269: error: 'lower' undeclared (first use in this function)
>  ZmodF_poly.c:269: error: syntax error before 'temp'
>  make[2]: *** [ZmodF_poly.o] Error 1
>  make[2]: Leaving directory
> `/afs/.nada.kth.se/pkg/sage/src/sage-2.8.12/spkg/build/flint-0.2.p4/src'
>
>
>  This is due to the fact that there is no typedef for u_int_t in include
> files.
>
>  Adding this definition in some file makes sage build OK.
>
>
>
>
> -
> This SF.net email is sponsored by: Splunk Inc.
> Still grepping through log files to find problems?  Stop.
> Now Search log events and configuration files using AJAX and a browser.
> Download your FREE copy of Splunk now >> http://get.splunk.com/
> ___

[sage-devel] Re: trying to define a function and find an approximation

[David Joyner]

On Nov 15, 2007 2:49 AM, William Stein <[EMAIL PROTECTED]> wrote:
>
> On Nov 15, 2007 1:45 AM, Dan Drake <[EMAIL PROTECTED]> wrote:
> >
> > I discovered Sage recently and am very excited about it. In grad school,
> > I came to be very good with Mathematica, and am now doing a postdoc
> > where I only have access to (an old copy of) Maple. I like the idea of
> > having my mathematical software being only a 'wget' away, and even more
> > I like the idea of being able to see how it works and change it as I see
> > fit.
> >
> > But I'm having difficulty even defining a relatively simple function and
> > finding a floating-point approximation. I want to do
> >
> >   f := x -> integrate(exp(t^2), t=0..x); (Maple)
> >   evalf(f(2));
> >
> >   f[x_] := Integrate[Exp[t^2], {t, 0, x}](Mathematica)
> >   N[f[2]]
> >
> > in Sage. I know Python, and Sage is built with Python, so I tried
> >
> >   sage: def f(x): integrate(exp(t^2), t, 0, x)
> >
> > which complains that "global name 't' is not defined" when I try to
> > evaluate it. I don't want a global variable, just a local one to do the
> > integration!
>
> You can define that function and compute the integral in Sage as
> follows:
>
> sage: assume(x > 0)
> sage: f(x,t) = integrate(exp(t^2), t, 0, x)
> sage: f
> (x, t) |--> -sqrt(pi)*I*erf(I*x)/2
> sage: a = f(x,0)
> sage: a
> -sqrt(pi)*I*erf(I*x)/2
>
> The assume is needed above because of how Maxima works (you'll be
> non-interactively
> asked for it if you don't give it).
>
> Unfortunately, Sage does not have an implementation of computing
> a numerical approximation of erf(a) when a is not real, as PARI only


In that case, what is going on here?


sage: w = var("w")
sage: f = lambda w: exp((w+sqrt(-1))^2)
sage: f(w)
e^(w + I)^2
sage: f(w).nintegral(w,0,2)[0]
-4.4746871004750179
sage: f = lambda w: real(exp((w+sqrt(-1))^2))
sage: f(w).nintegral(w,0,2)[0]
-4.4746871004750179
sage: f = lambda w: imag(exp((w+sqrt(-1))^2))
sage: f(w).nintegral(w,0,2)[0]
-1.2224121101763701



> provides this function in case a is real, and maxima also seems to
> only provide it in that case.   Thus you can't actually numerically evaluate
> the result at some point.
>
> You are the second person to request numerical evaluation of erf... at a
> complex argument this week (Paul Zimmerman requested the same
> thing a few days ago).   So I hope one of the Sage developers looks into
> this.  I've made it:
>
> http://trac.sagemath.org/sage_trac/ticket/1173
>
> I also made
>
> http://trac.sagemath.org/sage_trac/ticket/1174
>
> which is related.
>
> > What's the right way to go about all this? Like I said, I'm very excited
> > about Sage, but this is not such an auspicious start.
>
> Calculus is actually not at all the main focus of Sage or Sage development
> yet, unfortunately, though the calculus package is very powerful.  It's
> something we introduced pretty recently into Sage, but it will still take
> some time to get every reasonable thing implemented, which very much
> is our goal.   We need more people-power though, at least for the calculus
> part of Sage (where there are currently very few developers compared
> to other parts of Sage).
>
>  -- William
>
>
> >
>

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[sage-devel] Re: Coercion trouble

[David Roe]

The code for residue field is currently not correct.  In converting a number
field element, it expresses it in terms of a power basis for the number
field and then casts the coefficients to Z/pZ.  But the coefficients can
have denominators divisible by p in general.  That's probably what's causing
your problem.

William and I have been talking about rewriting it so that residue field
computes a p-maximal order and then does things appropriately, but it hasn't
gotten done yet.
David

On Nov 15, 2007 8:57 PM, mabshoff <
[EMAIL PROTECTED]> wrote:

>
>
>
> On Nov 16, 1:30 am, Iftikhar Burhanuddin <[EMAIL PROTECTED]> wrote:
> > Hi folks,
>
> Hello Ifti,
>
> >
> > I run into some coercion trouble when I reduce a fourier coefficient
> > of a cusp form modulo a prime ideal. (See below.)
> >
> > Any idea how I can avoid this?
> >
>
> No clue for now, but that looks like a bug to me. Please file a bug
> report.
>
> Cheers,
>
> Michael
>
> > Regards,
> > Ifti
> > ===
> >
> > sage: M = ModularSymbols(77, 2)
> >
> > sage: s = M.cuspidal_subspace().new_subspace()
> >
> > sage: N = s.decomposition()
> >
> > sage: f = N[3].q_eigenform()
> >
> > sage: R = f.base_ring()
> >
> > sage: K = R.number_field()
> >
> > sage: O = K.ring_of_integers()
> >
> > sage: I = O.ideal(7)
> >
> > sage: F = O.residue_field(I)
> >
> > sage: F(f[2])
> >
> ---
> >  Traceback (most recent call
> > last)
> >
> > /home/burhanud/tau_nov14_07/ in ()
> >
> > /home/burhanud/tau_nov14_07/residue_field.pyx in
> > sage.rings.residue_field.ResidueFiniteField_givaro.__call__()
> >
> > /home/burhanud/tau_nov14_07/finite_field_givaro.pyx in
> > sage.rings.finite_field_givaro.FiniteField_givaro.__call__()
> >
> > : unable to coerce
> >
>

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[sage-devel] Re: Coercion trouble

[David Roe]

I lost internet connection and then lost the traceback when my machine
restarted, so if you could open a ticket on the __rpath issue, I would
apprectiate it.

The residue field problem is ticket 1183.
David

On Nov 15, 2007 9:29 PM, David Roe <[EMAIL PROTECTED]> wrote:

> I lost internet connection and then lost the traceback when my machine
> restarted, so if you could open a ticket on the __rpath issue, I would
> apprectiate it.
>
> I'll open a ticket on the residue field issue though. Or check to see if
> one exists already.
> David
>
>
> On Nov 15, 2007 9:13 PM, mabshoff <[EMAIL PROTECTED]>
> wrote:
>
> >
> >
> >
> > On Nov 16, 3:05 am, "David Roe" <[EMAIL PROTECTED]> wrote:
> > > The code for residue field is currently not correct.  In converting a
> > number
> > > field element, it expresses it in terms of a power basis for the
> > number
> > > field and then casts the coefficients to Z/pZ.  But the coefficients
> > can
> > > have denominators divisible by p in general.  That's probably what's
> > causing
> > > your problem.
> > >
> > > William and I have been talking about rewriting it so that residue
> > field
> > > computes a p-maximal order and then does things appropriately, but it
> > hasn't
> > > gotten done yet.
> > > David
> >
> > David,
> >
> > could you please open a ticket then. I was also wondering if you ever
> > opened a ticket about the --rpath issue that caused compilation
> > failure on OSX when moving the install. I can't find it, so if you
> > don't want to open that one let me know and I will do.
> >
> > Cheers,
> >
> > Michael
> >
> > >
> > > On Nov 15, 2007 8:57 PM, mabshoff <
> > >
> > > [EMAIL PROTECTED]> wrote:
> > >
> > > > On Nov 16, 1:30 am, Iftikhar Burhanuddin < [EMAIL PROTECTED]> wrote:
> > > > > Hi folks,
> > >
> > > > Hello Ifti,
> > >
> > > > > I run into some coercion trouble when I reduce a fourier
> > coefficient
> > > > > of a cusp form modulo a prime ideal. (See below.)
> > >
> > > > > Any idea how I can avoid this?
> > >
> > > > No clue for now, but that looks like a bug to me. Please file a bug
> > > > report.
> > >
> > > > Cheers,
> > >
> > > > Michael
> > >
> > > > > Regards,
> > > > > Ifti
> > > > > ===
> > >
> > > > > sage: M = ModularSymbols(77, 2)
> > >
> > > > > sage: s = M.cuspidal_subspace().new_subspace()
> > >
> > > > > sage: N = s.decomposition()
> > >
> > > > > sage: f = N[3].q_eigenform()
> > >
> > > > > sage: R = f.base_ring()
> > >
> > > > > sage: K = R.number_field()
> > >
> > > > > sage: O = K.ring_of_integers()
> > >
> > > > > sage: I = O.ideal(7)
> > >
> > > > > sage: F = O.residue_field(I)
> > >
> > > > > sage: F(f[2])
> > >
> > > >
> > ---
> > > > >  Traceback (most recent
> > call
> > > > > last)
> > >
> > > > > /home/burhanud/tau_nov14_07/ in ()
> > >
> > > > > /home/burhanud/tau_nov14_07/residue_field.pyx in
> > > > > sage.rings.residue_field.ResidueFiniteField_givaro.__call__()
> > >
> > > > > /home/burhanud/tau_nov14_07/finite_field_givaro.pyx in
> > > > > sage.rings.finite_field_givaro.FiniteField_givaro.__call__()
> > >
> > > > > : unable to coerce
> > > >
> >
>

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[sage-devel] Power series rings

[David Roe]

Hey all,
At some point in the near future I may try to bring the implementation of
power series rings more into line with the p-adics.  The single variable
case seems straightforward, but a something popped up for me when thinking
about the multivariable case.

What is the appropriate analogue of laurent series?  Is the key point for
laurent series that we allow bounded negative exponents?   Or that it's a
field?  Because allowing bounded negative exponents is not enough to always
have inverses: x + y has no inverse if we require the exponents of x and y
to be bounded away from negative infinity.
David

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[sage-devel] Re: interactive widgets in the notebook

[David Harvey]

On Nov 17, 2007, at 7:41 PM, William Stein wrote:

> I'm pretty excited about this!  I think it would be extremely  
> amazingly
> useful if you could make up some more examples like this one
>
> sage: a = Slider(1,10)
> sage: plot(sin(a()*x),-3,3)

Why not just

> plot(sin(a*x),-3,3)

instead of

> plot(sin(a()*x),-3,3)

?

david


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[sage-devel] Re: sage-2.8.13 release cycle: request for reviews

[David Harvey]

On Nov 18, 2007, at 4:16 AM, Robert Bradshaw wrote:

>> #1130
>
> This seems to rely on an earlier patch. (#1120?) See comments on trac.

I'm very concerned about this patch. It is not the case that the LCM  
of the orders of all elements of E(GF(q)) will equal the order of E(GF 
(q)). I haven't tried the code, but if I understand the code  
correctly, it will go into an infinite loop on such cases, and it may  
well give incorrect results in other cases.

For example:

sage: K. = GF(5^3)
sage: K.polynomial()
a^3 + 3*a + 3
sage: E = EllipticCurve([3*a^2 + 2, 2*a + 4])
sage: E
Elliptic Curve defined by y^2  = x^3 + (3*a^2+2)*x + (2*a+4) over  
Finite Field in a of size 5^3
sage: LCM([P.order() for P in E.points()])
32
sage: len(E.points())
128

david


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[sage-devel] Re: sage-2.8.13 release cycle: request for reviews

[David Harvey]

On Nov 18, 2007, at 8:49 AM, Martin Albrecht wrote:

>
> On Sunday 18 November 2007, David Harvey wrote:
>> On Nov 18, 2007, at 4:16 AM, Robert Bradshaw wrote:
>>>> #1130
>>>
>>> This seems to rely on an earlier patch. (#1120?) See comments on  
>>> trac.
>>
>> I'm very concerned about this patch. It is not the case that the LCM
>> of the orders of all elements of E(GF(q)) will equal the order of E 
>> (GF
>> (q)). I haven't tried the code, but if I understand the code
>> correctly, it will go into an infinite loop on such cases, and it may
>> well give incorrect results in other cases.
>
> Yes, it should not go in, my bad, sorry. I quickly hacked to  
> together the
> algorithm in "Elliptic Curves" by Lawrence Washington and  
> apparently screwed
> up badly on the way. He writes:
>
> 7. If we are looking for the #E(F_q), then repeat steps (1)-(6)  
> [finding the
> order of a point, malb] with randomly chosen points in E(F_q) until  
> the
> greatest common multiple of the orders divides only one integer N  
> with q +
> 1 -2*sqrt(q) <= N <= q + 1 + 2*sqrt(q). Then N = #E(F_q).
>
> Apparently I overread the 'divides' part. Also, what is a   
> 'greatest common
> divisor'?

I still don't believe this algorithm.

Look at this example:

sage: K. = GF(3^4)
sage: K.polynomial()
a^4 + 2*a^3 + 2
sage: E = EllipticCurve(K, [2*a^2 + 2*a + 2, 2*a^3 + 2*a + 1])
sage: points = E.points()
sage: len(points)
100
sage: LCM([P.order() for P in points])
10

The hasse bound says the the number of points must be in [64, 100].  
But if the best we can do is show divisibility by 10, that's not  
enough information: it could be 70, 80, 90, or 100.

Does Washington place any other restrictions on the finite field or  
on the curve?

david


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[sage-devel] Re: sage-2.8.13 release cycle: request for reviews

[David Harvey]

On Nov 19, 2007, at 4:55 AM, Martin Albrecht wrote:

>> I still don't believe this algorithm.
>>
>> Look at this example:
>>
>> sage: K. = GF(3^4)
>> sage: K.polynomial()
>> a^4 + 2*a^3 + 2
>> sage: E = EllipticCurve(K, [2*a^2 + 2*a + 2, 2*a^3 + 2*a + 1])
>> sage: points = E.points()
>> sage: len(points)
>> 100
>> sage: LCM([P.order() for P in points])
>> 10
>>
>> The hasse bound says the the number of points must be in [64, 100].
>> But if the best we can do is show divisibility by 10, that's not
>> enough information: it could be 70, 80, 90, or 100.
>>
>> Does Washington place any other restrictions on the finite field or
>> on the curve?
>
> Hi David,
>
> I cannot see any restriction placed on the curves or the fields  
> used. Justin
> pointed me to the errate for Washington's book but it only contains  
> the
> remark, that the greatest common multiple is indeed the least common
> multiple. Revisiting the group structure of elliptic curves I now  
> also cannot
> see why this algorithm would work: the group of points of an  
> elliptic curve
> over a finite field is either isomorphic to Z_n or Z_n1 + Z_n2  
> where n1 | n2
> (also from Washington's book). In the later case we'll have points  
> of orders
> n1 and n2 and their LCM will be n2.
>
> So the trac ticket should be invalidated.
>
> Does this sound about right?

Yeah.

So I guess either you have to look at John Cremona's code, figure out  
how difficult it would be to wrap, or look up another algorithm and  
implement that instead.

Further down the road, Drew Sutherland is thinking about writing a C+ 
+ library for computing things like orders, exponents, structures of  
generic abelian groups. Basically you give it a "black box" that  
knows how to add group elements, invert group elements, produce the  
identity, and produce random elements, and it efficiently works out  
the structure of the group, etc. No firm plans yet though I'm  
meeting up with him next week to discuss this. It will be some time  
before it's written and wrapped in sage.

david


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[sage-devel] Re: sage-2.8.13 release cycle: request for reviews [abelian groups]

[David Joyner]

On Nov 19, 2007 6:33 AM, David Harvey <[EMAIL PROTECTED]> wrote:
>
>
>
> On Nov 19, 2007, at 4:55 AM, Martin Albrecht wrote:
>
> >> I still don't believe this algorithm.
> >>
> >> Look at this example:
> >>
> >> sage: K. = GF(3^4)
> >> sage: K.polynomial()
> >> a^4 + 2*a^3 + 2
> >> sage: E = EllipticCurve(K, [2*a^2 + 2*a + 2, 2*a^3 + 2*a + 1])
> >> sage: points = E.points()
> >> sage: len(points)
> >> 100
> >> sage: LCM([P.order() for P in points])
> >> 10
> >>
> >> The hasse bound says the the number of points must be in [64, 100].
> >> But if the best we can do is show divisibility by 10, that's not
> >> enough information: it could be 70, 80, 90, or 100.
> >>
> >> Does Washington place any other restrictions on the finite field or
> >> on the curve?
> >
> > Hi David,
> >
> > I cannot see any restriction placed on the curves or the fields
> > used. Justin
> > pointed me to the errate for Washington's book but it only contains
> > the
> > remark, that the greatest common multiple is indeed the least common
> > multiple. Revisiting the group structure of elliptic curves I now
> > also cannot
> > see why this algorithm would work: the group of points of an
> > elliptic curve
> > over a finite field is either isomorphic to Z_n or Z_n1 + Z_n2
> > where n1 | n2
> > (also from Washington's book). In the later case we'll have points
> > of orders
> > n1 and n2 and their LCM will be n2.
> >
> > So the trac ticket should be invalidated.
> >
> > Does this sound about right?
>
> Yeah.
>
> So I guess either you have to look at John Cremona's code, figure out
> how difficult it would be to wrap, or look up another algorithm and
> implement that instead.
>
> Further down the road, Drew Sutherland is thinking about writing a C+
> + library for computing things like orders, exponents, structures of
> generic abelian groups. Basically you give it a "black box" that
> knows how to add group elements, invert group elements, produce the
> identity, and produce random elements, and it efficiently works out
> the structure of the group, etc. No firm plans yet though I'm


How do you produce a random element without knowing the
generators of the group? And, for an abelian group, the
generators give you the "invariants" quickly don't they?



> meeting up with him next week to discuss this. It will be some time
> before it's written and wrapped in sage.
>
> david
>
>
>
> >
>

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[sage-devel] Re: sage-2.8.13 release cycle: request for reviews [abelian groups]

[David Harvey]

On Nov 19, 2007, at 6:59 AM, David Joyner wrote:

>> Further down the road, Drew Sutherland is thinking about writing a C+
>> + library for computing things like orders, exponents, structures of
>> generic abelian groups. Basically you give it a "black box" that
>> knows how to add group elements, invert group elements, produce the
>> identity, and produce random elements, and it efficiently works out
>> the structure of the group, etc. No firm plans yet though I'm
>
> How do you produce a random element without knowing the
> generators of the group? And, for an abelian group, the
> generators give you the "invariants" quickly don't they?

Oh boy you guys have exhausted my meagre knowledge on this  
subject pretty quickly :-)

I think the idea is supposed to be that part of the definition of the  
black box is that it can produce random elements, regardless of  
whether you know the generators. So for example, suppose our group is  
the multiplicative group of Z/NZ, for some large N whose  
factorisation we don't know. It's pretty easy to produce random  
elements of this group (or at least, every time you write down a  
random integer in [0, N), you have either found a random element, or  
can easily find a non-trivial factor of N by taking the gcd with N).  
But it's very hard to find generators (should be roughly equivalent  
to factoring N?).

And yes, once you have the generators, I guess you have everything  
else very easily.

david


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[sage-devel] Re: sage-2.8.13 release cycle: request for reviews [abelian groups]

[David Joyner]

On Nov 19, 2007 7:27 AM, David Harvey <[EMAIL PROTECTED]> wrote:
>
>
> On Nov 19, 2007, at 6:59 AM, David Joyner wrote:
>
> >> Further down the road, Drew Sutherland is thinking about writing a C+
> >> + library for computing things like orders, exponents, structures of
> >> generic abelian groups. Basically you give it a "black box" that
> >> knows how to add group elements, invert group elements, produce the
> >> identity, and produce random elements, and it efficiently works out
> >> the structure of the group, etc. No firm plans yet though I'm
> >
> > How do you produce a random element without knowing the
> > generators of the group? And, for an abelian group, the
> > generators give you the "invariants" quickly don't they?
>
> Oh boy you guys have exhausted my meagre knowledge on this
> subject pretty quickly :-)
>
> I think the idea is supposed to be that part of the definition of the
> black box is that it can produce random elements, regardless of
> whether you know the generators. So for example, suppose our group is
> the multiplicative group of Z/NZ, for some large N whose
> factorisation we don't know. It's pretty easy to produce random
> elements of this group (or at least, every time you write down a
> random integer in [0, N), you have either found a random element, or
> can easily find a non-trivial factor of N by taking the gcd with N).
> But it's very hard to find generators (should be roughly equivalent
> to factoring N?).


Okay. But this raises another (possibly dumber) question. Say
N is the product of 2 very large primes. In the case of G =
ZZ/NZZ, addition, inversion and random elements can be produced
in polynomial time I asume. Knowing the group structure of G, ie
the invariants, is tantamount to knowing the factorization of N, isn't it?
If "yes", then what does "efficiently works" mean?

I'm just curious, not trying to be discouraging. In fact, the opposite - it
sounds potentially very interesting...


>
> And yes, once you have the generators, I guess you have everything
> else very easily.
>
>
> david
>
>
> >
>

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[sage-devel] Fwd: [Maxima] Interesting Comment re Mathematica vs Everybody Else

[David Joyner]

FYI (scroll down to see the mention of SAGE)


-- Forwarded message --
From: Miguel Marco <[EMAIL PROTECTED]>
Date: Nov 19, 2007 7:13 AM
Subject: Re: [Maxima] Interesting Comment re Mathematica vs Everybody Else
To: [EMAIL PROTECTED]



> I have not played with Maple or MuPAD for five years or so, and so
> cannot really compare them now.  Five years ago Mathematica seemed to
> handle more of the problems that I threw at it, and that was before I
> knew anyone from Wolfram.  Every few months I look at Axiom, Maxima,
> sympy etc..., but frankly they are not close to being in the same
> league, and seem to be losing ground over time
I don't know much about Mathematica, but some of my coleagues use Maple once
in a while, and i agree with you about the fact that, often, the same problem
requires more work from the user to be solved in maxima than in maple.
Anyways, it is not a question of capability (at the end, both are
Turing-complete), but of usability. Anyways, all general purpose CAS that i
have seen make some mistakes in specific cases, which forced the user to
think twice befure using them for serious stuff beyond education.

> (I would have expected
> computer algebra to be a place where open source would shine, but
> alas, it seems not.)  The Sage project seems to have promise, but
> right now it looks like a bunch of distinct tools and a lot of duct
> tape.
> The more specialized tools like MacCaulay, CoCoA, Gap, Pari/GP, 4ti2,
> etc. are amazing in their niches, but have no pretenses to being
> widely applicable.
>
That is exactly the point: math researchers usually don't want to use a
general purpose tool, but the killer-app in their specific field. It makes
little sense to calculate groebner basis, or character tables with
Mathematica, Maple or Maxima. Hence, the same researchers that use these
specialized tools, help improving them (after all, they are the ones that do
research in those very specific algorithms). And thats how specifc open
source CAS keep improving, but general purpose ones stay in a second level.
One exception would be Axiom, that, besides a general purpose CAS, can handle
nested definitions of algebraic structures (i don't know any other CAS that
can do this), which can be usefull for some specific lines of research.

Besides that, i consider that the main target for general purpose CAS'es is
actually education, and in that niche efficiency of algorithms is secondary
to pedagogical questions (such as easyness of learning). Considering that, i
think that differences in that aspect between Mathematica, Maple, and Maxima
(depending on the GUI) are no big enough to say that Maxima plays in another
league.

Best:


Miguel Marco Buzunariz
Departamento de Matematicas
Universidad de Zaragoza.

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[sage-devel] Re: sage-2.8.13 release cycle: request for reviews [abelian groups]

[David Harvey]

On Nov 19, 2007, at 10:10 AM, David Joyner wrote:

>> I think the idea is supposed to be that part of the definition of the
>> black box is that it can produce random elements, regardless of
>> whether you know the generators. So for example, suppose our group is
>> the multiplicative group of Z/NZ, for some large N whose
>> factorisation we don't know. It's pretty easy to produce random
>> elements of this group (or at least, every time you write down a
>> random integer in [0, N), you have either found a random element, or
>> can easily find a non-trivial factor of N by taking the gcd with N).
>> But it's very hard to find generators (should be roughly equivalent
>> to factoring N?).
>
>
> Okay. But this raises another (possibly dumber) question. Say
> N is the product of 2 very large primes. In the case of G =
> ZZ/NZZ, addition, inversion and random elements can be produced
> in polynomial time I asume.

Yes. (In fact, almost linear time.)

> Knowing the group structure of G, ie
> the invariants, is tantamount to knowing the factorization of N,  
> isn't it?

Yes.

> If "yes", then what does "efficiently works" mean?

"Efficiently works" means that it has a very efficient implementation  
of baby-step/giant-step and various algorithms built on top of that.  
Of course this is a terrible algorithm for factoring integers, it's  
not even sub-exponential, in the case of two large prime factors.  
With the group Z/NZ, all the best algorithms take advantage of extra  
structure. But if you have a "generic" group where you don't know  
much else about the structure --- all you know is how to add and  
invert --- then baby-step/giant-step is pretty much the best you can do.

Drew's thesis makes good reading on this topic:

http://groups.csail.mit.edu/cis/theses/sutherland-phd.pdf

david


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[sage-devel] Re: Projects

[David Joyner]

On Nov 19, 2007 12:21 PM, Martin Albrecht <[EMAIL PROTECTED]> wrote:
>
> Hi there,
>
> at Sage Days 6 Stefan Müller-Stach
>
>http://hodge.mathematik.uni-mainz.de/~stefan/index.html
>
> babelfish translation:
>
> http://babelfish.altavista.com/babelfish/tr?lp=de_en&url=http%3A//hodge.mathematik.uni-mainz.de/%7Estefan/index.html
>
> asked me whether the Sage project would like to name some projects suitable
> for a Diplomarbeit for some of his students.
>
> If you don't know the German system: it is safe to assume a "Diplomarbeit" is
> like a Master's thesis (except that you usually do a Diplom before pursuing a
> PhD). The idea is that we/you/the Sage developers name a project (in number
> theory) which is suitable for a Diplomarbeit (i.e. challenging enough but not
> overwhelming, timeframe: roughly a year) and Stefan tries to pass this
> project on to one of his students.
>
> To me this seems like a nice way to get stuff implemented that one hardly gets
> around to implement.
>
> Also, he is thinking about setting up a Sage seminar which could provide a
> similar 'service' for Sage: i.e. Students get credits for working on Sage.
> This would be suitable for more short term projects.
>
> Thoughts?


Just to narrow things down a bit, is it fair to say that the topics
his students
will probably focus on would be algebraic geometry and/or algebraic number
theory (not calculus or differential equations or something like that)?

I think we are still lacking a good implementation of an algorithm computing
Riemann-Roch spaces. I'm not sure if that is too far afield or not though...


>
> Martin
>
> PS: Stefan, I hope I represented your idea correctly.
> --
> name: Martin Albrecht
> _pgp: http://pgp.mit.edu:11371/pks/lookup?op=get&search=0x8EF0DC99
> _www: http://www.informatik.uni-bremen.de/~malb
> _jab: [EMAIL PROTECTED]
>
>
> >
>

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[sage-devel] Re: writing a new class

[David Roe]

This is one of the things I'd been planning on adding to the new programming
guide.

Your issue is that you're creating a new directory.  When you do that, you
have to add that directory to the list of packages at the bottom of
setup.pyin sage-root/devel/sage-branch/
You should also put an __init__.py file in your new directory, and probably
also an all.py file that controls the imports of that directory for the sage
namespace.

Things get more complicated if you want to add cython files, but you're not
doing that at the moment.
David

On Nov 20, 2007 7:03 AM, Jason Grout <[EMAIL PROTECTED]> wrote:

>
> Hi everyone,
>
> I have a simple question: I'm trying to write a new class in a new file.
>  How do I get that file to show up in Sage?  In this case, I'm trying
> to write a menu.py file under the sage/server/notebook/widgets directory
> (a  new directory).  But when starting up SAGE with sage -br, it doesn't
> ever say anything about my file and I can't import my file like a normal
> Sage object (i.e., from sage.server.notebook.widgets import menu).
>
> Thanks,
>
> Jason
>
>
> >
>

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[sage-devel] Re: writing a new class

[David Harvey]

On Nov 20, 2007, at 7:03 AM, Jason Grout wrote:

> Hi everyone,
>
> I have a simple question: I'm trying to write a new class in a new  
> file.
>   How do I get that file to show up in Sage?  In this case, I'm trying
> to write a menu.py file under the sage/server/notebook/widgets  
> directory
> (a  new directory).  But when starting up SAGE with sage -br, it  
> doesn't
> ever say anything about my file and I can't import my file like a  
> normal
> Sage object (i.e., from sage.server.notebook.widgets import menu).

Someone who understands the sage build system will probably give you  
a better answer in a moment but since I'm already awake

You might need to add 'sage.server.notebook.widgets' near the bottom  
of setup.py. That script copies files into the place where SAGE knows  
where to find them.

david


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[sage-devel] Re: is anybody interesting lie groups, etc.

[David Joyner]

I think this is interesting but I wonder how easy it is to compile.
Also, is there also a plan to include lie?


++

On 11/21/07, William Stein <[EMAIL PROTECTED]> wrote:
>
> Hi Sage Devel,
>
> If you noticed the publicity a few months ago about E8, "the Sage
> supercomputer", etc.,
> then you might be interested in this project.The software here,
> which is a mostly
> well documented (but sometimes not) not unpleasant C++ program
>
>  http://www.liegroups.org/software/download/
>
> was the code used (run on sage.math.washington.edu) to do "the E8 
> calculation".
> It is actually much more general code, capable I think of doing many 
> interesting
> things related to lie groups, and do them very very quickly (that's
> the key point).
> It's completely unique, interesting, and powerful code.
>
> A few minutes ago I got word from the ATLAS of Lie Groups group that "William,
> Well, I think everybody has had their say and the conclusion is unanimous:
> Atlas is GPL. (There still is some discussion about which version of GPL
> and where to put the notification. This will be straightened out soon.)"
>
> So is anybody interested in thinking through how this could perhaps be
> made a standard and useful part of Sage?   Let me know.
>
> --
> William Stein
> Associate Professor of Mathematics
> University of Washington
> http://wstein.org
>
> >
>

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[sage-devel] Re: ArithmeticError

[David Roe]

It's fixed (patch posted to trac).  As suspected, it was a bug introduced in
the ell_rational_field refactoring.
David


On Nov 21, 2007 12:25 PM, William Stein <[EMAIL PROTECTED]> wrote:

>
> On Nov 20, 2007 1:40 PM, Paul Zimmermann <[EMAIL PROTECTED]> wrote:
> >William,
> >
> > sage told me to report you, thus I do:
> [... see below]
>
> For the particular curve you're considering mwrank (via sage's rank
> command)
> can compute the rank -- which is what you want -- in 0.5 seconds, so maybe
> you can use .rank() instead?
>
> {{{id=24|
> e = EllipticCurve([0, 33076156654533652066609946884, 0,
> 347897536144342179642120321790729023127716119338758604800,
> 114112815436927429551902303280680424778815462104985764887003237028585178\
> 135281664])
> }}}
>
> {{{id=27|
> time e.rank()
> ///
> 1
> CPU time: 0.00 s,  Wall time: 0.46 s
> }}}
>
> That said, the fact that  e.torsion_order() fails is certainly a bug:
>
> {{{id=29|
> e.torsion_order()
> ///
> Traceback (most recent call last):
>  File "", line 1, in 
>  File "/Users/was/sage_notebook/worksheets/admin/23/code/91.py", line
> 4, in 
> ...
>self.__torsion_subgroup =
> rational_torsion.EllipticCurveTorsionSubgroup(self, flag)
>  File
> "/Users/was/s/local/lib/python2.5/site-packages/sage/schemes/elliptic_curves/rational_torsion.py",
> line 56, in __init__
>self.__E.__pari_double_prec()
> AttributeError: 'EllipticCurve_rational_field' object has no attribute
> '_EllipticCurveTorsionSubgroup__pari_double_prec'
> }}}
>
> This is now trac #1237
>   http://trac.sagemath.org/sage_trac/ticket/1237
> and it probably won't be too hard to fix.  I suspect it was caused perhaps
> by David Roe's recent refactoring of the code for elliptic curve over QQ,
> but I couldn't be completely wrong.
>
>
> > sage: d = 919681/88529281
> > sage: _ = magma.eval('K := Rationals()')
> > sage: _ = magma.eval('P:=ProjectiveSpace(K,2)')
> > sage: def rank(d):
> > :s='f := (x^2+y^2)*z^2-z^4-('
> > :s=''.join([s, repr(d), ')*x^2*y^2;'])
> > :magma.eval(s)
> > :magma.eval('C:=Curve(P,f);')
> > :E = magma('EllipticCurve(C,C![0,1,1])')
> > :l = E.aInvariants()
> > :EE = EllipticCurve(map(Integer,l))
> > :return EE.simon_two_descent()[0]
> > :
> > sage: rank(d)
> >
> ---
> > Traceback (most recent call
> last)
> >
> > /home/zimmerma/ in ()
> >
> > /home/zimmerma/ in rank(d)
> >
> > /usr/local/sage-2.8.12/sage/local/lib/python2.5/site-packages/sage/schemes/elliptic_curves/ell_rational_field.py
> in simon_two_descent(self, verbose, lim1, lim3, limtriv, maxprob,
> limbigprime)
> > 858 (8, 8)
> > 859 """
> > --> 860 if self.torsion_order() % 2 == 0:
> > 861 raise ArithmeticError, "curve must not have rational
> 2-torsion\nThe *only* reason for this is that I haven't finished
> implementing the wrapper\nin this case.  It wouldn't be too
> difficult.\nPerhaps you could do it?!  Email me ([EMAIL PROTECTED])."
> > 862 F = self.integral_weierstrass_model()
> >
> > /usr/local/sage-2.8.12/sage/local/lib/python2.5/site-packages/sage/schemes/elliptic_curves/ell_rational_field.py
> in torsion_order(self)
> >1743 return self.__torsion_order
> >1744 except AttributeError:
> > -> 1745 self.__torsion_order = self.torsion_subgroup
> ().order()
> >1746 return self.__torsion_order
> >1747
> >
> > /usr/local/sage-2.8.12/sage/local/lib/python2.5/site-packages/sage/schemes/elliptic_curves/ell_rational_field.py
> in torsion_subgroup(self, flag)
> >1781 return self.__torsion_subgroup
> >1782 except AttributeError:
> > -> 1783 self.__torsion_subgroup =
> rational_torsion.EllipticCurveTorsionSubgroup(self, flag)
> >1784 return self.__torsion_subgroup
> >1785
> >
> > /usr/local/sage-2.8.12/sage/local/lib/python2.5/site-packages/sage/schemes/elliptic_curves/rational_torsion.py
> in __init__(self, E, flag)
> >  54 G = self.__E.pari_curve().elltors(flag)
> >  55 except RuntimeError:
> > ---> 56 self.__E.__pari_double_prec()
> >  57 if G is None:
> >  58 raise RuntimeError, "Could not compute torsion
> subgroup"
> >
> > : 'EllipticCurve_rational_field'
> object has no attribute '_EllipticCurveTorsionSubgroup__pari_double_prec'
> >
> > Paul
> >
>
>
>
> --
> William Stein
> Associate Professor of Mathematics
> University of Washington
> http://wstein.org
>
> >
>

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[sage-devel] abelian groups

[David Harvey]

Hi all,

I'd like to discuss this abelian group thing a bit further, from the  
point of view of design issues rather than algorithms.

Currently in SAGE the situation appears to be the following. An  
AbelianGroup represents a (not necessarily finite) abelian group  
whose structure is *known*; i.e. to even create the group object, you  
need to specify generators and invariants. In fact, even the parent  
class Group derives from ParentWithGens, so it seems to be impossible  
to define a "group" whose generators are unknown.

What I want to be able to do is create an object representing an  
abelian group whose structure is *not* a priori known, i.e. is  
expensive to compute. This is analogous to, for example, creating a  
matrix by specifying the entries, and then later on asking for other  
information like the rank, which is an expensive computation, and is  
subsequently cached.

The main example I'm interested in at the moment is:

* The group of K-rational points on a jacobian of an algebraic curve  
over k, where k and K/k are finite fields.

Other examples:

* The class group of a number field.
* The multiplicative group of Z/nZ.
* Like the Jacobian example above, but with the fields not finite  
(e.g. the rational points on an elliptic curve over Q)

In these examples, it is easy to describe the group law, and it is  
relatively easy to write down some elements of the group, but it is  
difficult (or even impossible!) to compute the structure of the group.

Consider the example of an elliptic curve E over a finite field k.  
Currently, when I call E.abelian_group(), it tries to compute the  
structure and return that as an AbelianGroup:

sage: F = GF(17)
sage: E = EllipticCurve(F, [2, 5])
sage: E.abelian_group()
(Multiplicative Abelian Group isomorphic to C18, ((5 : 2 : 1),))

But I would like to be able to call something like  
E.abstract_abelian_group() and have it just return something like an  
AbstractAbelianGroup object, whose elements are something like  
AbstractAbelianGroupElements. This operation doesn't attempt to  
compute the group structure at all. The elements should remember that  
they came from that elliptic curve, and I should be able to create  
elements (by specifying their co-ordinates), and I should be able to  
perform arithmetic on elements. The AbstractAbelianGroup class should  
then have generic implementations of things like finding orders of  
elements, computing the exponent of the group, computing the  
structure of the group, which are then cached. (The reason I'm  
starting this thread at all is because I want to come up with a sane  
way to put these kind of generic group algorithms into SAGE.)

Somehow at the moment in SAGE it's very difficult to separate the  
"group structure" from the "elliptic curve" structure. For example,  
suppose I have an elliptic curve over Q, and I want to work with  
points defined over some number field K/Q. Currently I think the only  
option I have is to base extend the curve to K, because points need  
to "belong" to the curve. But mathematically that shouldn't be  
necessary; I should be able to talk about K-valued points of a curve  
over Q. If I base-extend to K, I lose the information that the curve  
was really defined over Q (which might make certain computations  
easier). So what I would like to be able to do is call  
E.group_over_field(K) which returns an abstract abelian group.

Maybe what I really want is a "ParentWithoutGens" base class :-)

I'm really unsure of how to proceed with this. Especially since there  
are difficult coercion issues lurking in the background. Any thoughts  
would be most appreciated.

david


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[sage-devel] Re: abelian groups

[David Joyner]

On Nov 22, 2007 9:35 AM, David Harvey <[EMAIL PROTECTED]> wrote:
>
> Hi all,
>
> I'd like to discuss this abelian group thing a bit further, from the
> point of view of design issues rather than algorithms.
>
> Currently in SAGE the situation appears to be the following. An
> AbelianGroup represents a (not necessarily finite) abelian group
> whose structure is *known*; i.e. to even create the group object, you
> need to specify generators and invariants. In fact, even the parent
> class Group derives from ParentWithGens, so it seems to be impossible
> to define a "group" whose generators are unknown.
>
> What I want to be able to do is create an object representing an
> abelian group whose structure is *not* a priori known, i.e. is
> expensive to compute. This is analogous to, for example, creating a
> matrix by specifying the entries, and then later on asking for other
> information like the rank, which is an expensive computation, and is
> subsequently cached.
>
> The main example I'm interested in at the moment is:
>
> * The group of K-rational points on a jacobian of an algebraic curve
> over k, where k and K/k are finite fields.
>
> Other examples:
>
> * The class group of a number field.
> * The multiplicative group of Z/nZ.
> * Like the Jacobian example above, but with the fields not finite
> (e.g. the rational points on an elliptic curve over Q)
>
> In these examples, it is easy to describe the group law, and it is
> relatively easy to write down some elements of the group, but it is
> difficult (or even impossible!) to compute the structure of the group.
>
> Consider the example of an elliptic curve E over a finite field k.
> Currently, when I call E.abelian_group(), it tries to compute the
> structure and return that as an AbelianGroup:
>
> sage: F = GF(17)
> sage: E = EllipticCurve(F, [2, 5])
> sage: E.abelian_group()
> (Multiplicative Abelian Group isomorphic to C18, ((5 : 2 : 1),))
>
> But I would like to be able to call something like
> E.abstract_abelian_group() and have it just return something like an
> AbstractAbelianGroup object, whose elements are something like
> AbstractAbelianGroupElements. This operation doesn't attempt to
> compute the group structure at all. The elements should remember that
> they came from that elliptic curve, and I should be able to create
> elements (by specifying their co-ordinates), and I should be able to
> perform arithmetic on elements. The AbstractAbelianGroup class should
> then have generic implementations of things like finding orders of
> elements, computing the exponent of the group, computing the
> structure of the group, which are then cached. (The reason I'm
> starting this thread at all is because I want to come up with a sane
> way to put these kind of generic group algorithms into SAGE.)
>
> Somehow at the moment in SAGE it's very difficult to separate the
> "group structure" from the "elliptic curve" structure. For example,
> suppose I have an elliptic curve over Q, and I want to work with
> points defined over some number field K/Q. Currently I think the only
> option I have is to base extend the curve to K, because points need
> to "belong" to the curve. But mathematically that shouldn't be
> necessary; I should be able to talk about K-valued points of a curve
> over Q. If I base-extend to K, I lose the information that the curve
> was really defined over Q (which might make certain computations
> easier). So what I would like to be able to do is call
> E.group_over_field(K) which returns an abstract abelian group.
>
> Maybe what I really want is a "ParentWithoutGens" base class :-)

It seems to me you want to copy

cdef class Group(sage.structure.parent_gens.ParentWithGens):

but with a bigger parent, calling it maybe AbstractGroup or
GroupWithoutGens or something.
If/when you know the generators, you coerce it into Group. Probably
it's much more
complicated to implement but the essence of what you want seems simple enough
conceptually. Instead of creating the ParentWithOutGens, maybe just go back into
sage.structure.parent.Parent?

In your example of an elliptic curve, it is possible that you do have generators
known, so maybe you want to have the option of specifying them
and coercing immediately?


>
> I'm really unsure of how to proceed with this. Especially since there
> are difficult coercion issues lurking in the background. Any thoughts
> would be most appreciated.
>
> david
>
>
> >
>

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[sage-devel] Re: abelian groups

[David Harvey]

On Nov 22, 2007, at 10:25 AM, William Stein wrote:

>
> On Nov 22, 2007 6:53 AM, David Joyner <[EMAIL PROTECTED]> wrote:
> \> On Nov 22, 2007 9:35 AM, David Harvey  
> <[EMAIL PROTECTED]> wrote:
>>>
>>> Hi all,
>>>
>>> I'd like to discuss this abelian group thing a bit further, from the
>>> point of view of design issues rather than algorithms.
>>>
>>> Currently in SAGE the situation appears to be the following. An
>>> AbelianGroup represents a (not necessarily finite) abelian group
>>> whose structure is *known*; i.e. to even create the group object,  
>>> you
>>> need to specify generators and invariants. In fact, even the parent
>>> class Group derives from ParentWithGens, so it seems to be  
>>> impossible
>>> to define a "group" whose generators are unknown.
>>>
>>> What I want to be able to do is create an object representing an
>>> abelian group whose structure is *not* a priori known, i.e. is
>>> expensive to compute. This is analogous to, for example, creating a
>>> matrix by specifying the entries, and then later on asking for other
>>> information like the rank, which is an expensive computation, and is
>>> subsequently cached.
>
> You should make an AbstractAbelianGroup class that derives from  
> ParentWithBase.

Hmmm but wouldn't it make more sense for AbelianGroup (i.e. the  
currently implemented one) to derive from AbstractAbelianGroup?

i.e. an AbelianGroup is an AbstractAbelianGroup where we happen to  
know the structure, and so can implement things like order, exponent  
etc more efficiently?

I guess then you have problems with multiple inheritance, since you  
want AbelianGroup to inherit from both AbstractAbelianGroup and  
ParentWithGens, both of which originally come from ParentWithBase.  
That's most unfortunate.

david


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[sage-devel] abelian groups

[David Harvey]

Hi all,

I'd like to discuss this abelian group thing a bit further, from the  
point of view of design issues rather than algorithms.

Currently in SAGE the situation appears to be the following. An  
AbelianGroup represents a (not necessarily finite) abelian group  
whose structure is *known*; i.e. to even create the group object, you  
need to specify generators and invariants. In fact, even the parent  
class Group derives from ParentWithGens, so it seems to be impossible  
to define a "group" whose generators are unknown.

What I want to be able to do is create an object representing an  
abelian group whose structure is *not* a priori known, i.e. is  
expensive to compute. This is analogous to, for example, creating a  
matrix by specifying the entries, and then later on asking for other  
information like the rank, which is an expensive computation, and is  
subsequently cached.

The main example I'm interested in at the moment is:

* The group of K-rational points on a jacobian of an algebraic curve  
over k, where k and K/k are finite fields.

Other examples:

* The class group of a number field.
* The multiplicative group of Z/nZ.
* Like the Jacobian example above, but with the fields not finite  
(e.g. the rational points on an elliptic curve over Q)

In these examples, it is easy to describe the group law, and it is  
relatively easy to write down some elements of the group, but it is  
difficult (or even impossible!) to compute the structure of the group.

Consider the example of an elliptic curve E over a finite field k.  
Currently, when I call E.abelian_group(), it tries to compute the  
structure and return that as an AbelianGroup:

sage: F = GF(17)
sage: E = EllipticCurve(F, [2, 5])
sage: E.abelian_group()
(Multiplicative Abelian Group isomorphic to C18, ((5 : 2 : 1),))

But I would like to be able to call something like  
E.abstract_abelian_group() and have it just return something like an  
AbstractAbelianGroup object, whose elements are something like  
AbstractAbelianGroupElements. This operation doesn't attempt to  
compute the group structure at all. The elements should remember that  
they came from that elliptic curve, and I should be able to create  
elements (by specifying their co-ordinates), and I should be able to  
perform arithmetic on elements. The AbstractAbelianGroup class should  
then have generic implementations of things like finding orders of  
elements, computing the exponent of the group, computing the  
structure of the group, which are then cached. (The reason I'm  
starting this thread at all is because I want to come up with a sane  
way to put these kind of generic group algorithms into SAGE.)

Somehow at the moment in SAGE it's very difficult to separate the  
"group structure" from the "elliptic curve" structure. For example,  
suppose I have an elliptic curve over Q, and I want to work with  
points defined over some number field K/Q. Currently I think the only  
option I have is to base extend the curve to K, because points need  
to "belong" to the curve. But mathematically that shouldn't be  
necessary; I should be able to talk about K-valued points of a curve  
over Q. If I base-extend to K, I lose the information that the curve  
was really defined over Q (which might make certain computations  
easier). So what I would like to be able to do is call  
E.group_over_field(K) which returns an abstract abelian group.

Maybe what I really want is a "ParentWithoutGens" base class :-)

I'm really unsure of how to proceed with this. Especially since there  
are difficult coercion issues lurking in the background. Any thoughts  
would be most appreciated.

david


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[sage-devel] patch for tut,tex

[David Joyner]

Hi:
I created a patch fixing someoutdated parts of the tutorial.
http://sagetrac.org/sage_trac/ticket/1251
- David Joyner

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[sage-devel] Re: SAGE for French Educational system

[David Joyner]

Thank you for your email!

I think this is a great idea.
Things like the "tutorial" or "constructions/cookbook" (or a suitable subset
of them) might need to be translated into French as well. They are
open source as well of course, so help yourself. Also, feel free to ask
for help if you need any from the email lists at
http://www.sagemath.org/lists.html

I'm cross-posting to sage-forum since there may be people there
interested in your project not on sage-devel.

- David Joyner



On Nov 24, 2007 5:20 PM, Philippe Saadé <[EMAIL PROTECTED]> wrote:
>
> Dear SAGE developers,
>
> i hope i am not bothering you to much with my mail. I am a math
> teacher in "Classe Préparatoire" in Lyon (France) so my students are
> school graduates and they prepare contests to enter famous "Grandes
> Écoles" (Engineers schools).
>
> The french educational administration has decided, many years ago, to
> promote the usage of computers for scientific purposes. They then have
> chosen two software : Maple and Matlab.
>
> I have the project to propose to "those who decide" to replace Maple
> (and maybe Matlab too) by Python based software. Of course, SAGE comes
> first in my mind.
>
> I know it is not a simple task because most teachers are now used to
> Maple and the new GUI of Maple is more intuitive. But it's not open
> source and it costs a lot... (so students download cracked versions)
>
> If i want to have a chance to convince these leaders, i must be able
> to prove that within a one year project, it is possible to adapt SAGE
> interface (mostly propose a french environment, and maybe french names
> to procedures and parameters) and provide a library of sample code
> (to prove that it fit the needs of math course in "Classes
> Préparatoire" and ease the adoption of SAGE by other teachers...)
>
> To achieve such a goal, i would work with a freelance consultant based
> in Lyon. Any code produced to adapt SAGE would be GPL licenced and
> fully open-source, without any delay in publication.
>
> I would like to have your opinion about that project and any advice or
> warning...
>
> I apologize for my poor English and for a rather cumbersome
> presentation. I hope to read from you soon.
>
> Best regards,
> Philippe Saadé
>
> >
>

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[sage-devel] new linear_codes patch

[David Joyner]

Hi:
I submitted a trac ticket with a link to a patch containing a few
improvements to linear_codes.py
http://sagetrac.org/sage_trac/ticket/1258
The new file is at
http://sage.math.washington.edu/home/wdj/patches/linear_code.py
if you want to look at the file directly. It passed sage -t.
- David Joyner

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[sage-devel] Re: Talk about SAGE at Les Trophees du Libre 2007 competition

[David Joyner]

I think this looks really excellent! Possibly there is a typo on page 27.
Did you mean "installation guide" where you said "programming guide"?


On Nov 25, 2007 10:14 AM, Martin Albrecht <[EMAIL PROTECTED]> wrote:
>
> Hi there,
>
> Sage is among the finalists of this year's Les Trophees du Libre competition
> in Paris, France.
>
> http://www.tropheesdulibre.org/+Finalists-projects?lang=en
>
> I am going to represent Sage at the finals (each project has to give a 30
> minute presentation) and thus prepared some slides available at:
>
> http://sage.math.washington.edu/home/malb/20071129%20-%20SAGE%20-%20Paris/
>
> cetril.pdf is the presentation, SAGE_Demo.sws the demo worksheet, and
> SAGE_Demo.pdf the PDF version of that demo. The target audience is a group of
> people who want to promote open-source but probably are not into mathematics
> at all. So presenting that we have a very sophisticated model for p-adic
> arithmetic and comparing Sage with Magma might not do the trick. (but Sage is
> in the 'scientific software' section, so it is okay to talk a little about
> mathematics ;-))
>
> The rules for the competition also indicate what the judges are going to be
> looking for:
>
> """
> All the software will be tested and evaluated according to the criteria set
> out below:
> - Innovation (coefficient of 3)
> - Functionality (coefficient of 3)
> - Quality/stability (coefficient of 3)
> - Durability (coefficient of 3)
> - Utility (coefficient of 4)
> - Documentation (coefficient of 3)
> - Ease of installation (coefficient of 1)
> - General renown (coefficient of -15)
> """
>
> I believe I've addressed these points implicitly (and I prefer to address them
> implicitly) but I'd appreciate feedback on the talk and demo. Also, what else
> could go into a demo for non-mathematicians? Is your name missing in the list
> of contributes (I generated that from the hg logs)?
>
> Cheers,
> Martin
>
> --
> name: Martin Albrecht
> _pgp: http://pgp.mit.edu:11371/pks/lookup?op=get&search=0x8EF0DC99
> _www: http://www.informatik.uni-bremen.de/~malb
> _jab: [EMAIL PROTECTED]
>
>
> >
>

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[sage-devel] Re: Talk about SAGE at Les Trophees du Libre 2007 competition

[David Joyner]

On Nov 25, 2007 10:59 AM, Martin Albrecht <[EMAIL PROTECTED]> wrote:
>
> On Sunday 25 November 2007, David Joyner wrote:
> > I think this looks really excellent! Possibly there is a typo on page 27.
> > Did you mean "installation guide" where you said "programming guide"?
>
> I meant:
>
> http://www.sagemath.org/doc/html/prog/index.html
>

On page 27 you seem to mention both "SAGE programming guide" and
"SAGE programming book" but do not include the SAGE installation
guide. Is that really what you intended?


>
> Cheers,
> Martin
>
>
> --
> name: Martin Albrecht
> _pgp: http://pgp.mit.edu:11371/pks/lookup?op=get&search=0x8EF0DC99
> _www: http://www.informatik.uni-bremen.de/~malb
> _jab: [EMAIL PROTECTED]
>
>
> >
>

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[sage-devel] Re: Talk about SAGE at Les Trophees du Libre 2007 competition

[David Roe]

I have to agree.  The slide where you list p-adic numbers, p-adic
L-functions and p-adic height pairings kinda jumped out at me.  While I'm
obviously interested in that kind of stuff, it won't appeal as much to a
non-specialist audience.

One might argue that as things implemented natively in Sage, these will
count toward the innovation category.  Perhaps, but then you should
emphasize that aspect, and tone down the words that the judges will have
never heard before (ie p-adics).  And I think Philippe does have a point
that Sage does a lot in the innovation category that is more widely
applicable.
David

On Nov 25, 2007 2:35 PM, Philippe Saade <[EMAIL PROTECTED]> wrote:

>
> Hi,
>
> don't you think you should add examples closer to "applied math" as
> Discreet Fourier transform, financial math, Finite Element Method, etc
> ?
>
> Some explanations :
> I am a french teacher and if the Jury is not aware of the importance
> of p-adic stuff or Elliptic Curve story, it will all appear quiet a
> mystery. A lot of research labs, university or schools could be happy
> with sage. And i think your presentation should insist on the fact
> that SAGE can be used by a huge amount of people and not only
> specialists (mathematicians...). It's true that SAGE is great for
> professional mathematicians, but it can also do a great job in
> education...
>
> More images might help the jury to be convinced of it...
>
> Hope my remarks will help (and let me say your work is very good
> already...)
>
> Best regards,
> philippe Saadé
>
> On Nov 25, 2007 4:14 PM, Martin Albrecht <[EMAIL PROTECTED]>
> wrote:
> >
> > Hi there,
> >
> > Sage is among the finalists of this year's Les Trophees du Libre
> competition
> > in Paris, France.
> >
> > http://www.tropheesdulibre.org/+Finalists-projects?lang=en
> >
> > I am going to represent Sage at the finals (each project has to give a
> 30
> > minute presentation) and thus prepared some slides available at:
> >
> >
> http://sage.math.washington.edu/home/malb/20071129%20-%20SAGE%20-%20Paris/
> >
> > cetril.pdf is the presentation, SAGE_Demo.sws the demo worksheet, and
> > SAGE_Demo.pdf the PDF version of that demo. The target audience is a
> group of
> > people who want to promote open-source but probably are not into
> mathematics
> > at all. So presenting that we have a very sophisticated model for p-adic
> > arithmetic and comparing Sage with Magma might not do the trick. (but
> Sage is
> > in the 'scientific software' section, so it is okay to talk a little
> about
> > mathematics ;-))
> >
> > The rules for the competition also indicate what the judges are going to
> be
> > looking for:
> >
> > """
> > All the software will be tested and evaluated according to the criteria
> set
> > out below:
> > - Innovation (coefficient of 3)
> > - Functionality (coefficient of 3)
> > - Quality/stability (coefficient of 3)
> > - Durability (coefficient of 3)
> > - Utility (coefficient of 4)
> > - Documentation (coefficient of 3)
> > - Ease of installation (coefficient of 1)
> > - General renown (coefficient of -15)
> > """
> >
> > I believe I've addressed these points implicitly (and I prefer to
> address them
> > implicitly) but I'd appreciate feedback on the talk and demo. Also, what
> else
> > could go into a demo for non-mathematicians? Is your name missing in the
> list
> > of contributes (I generated that from the hg logs)?
> >
> > Cheers,
> > Martin
> >
> > --
> > name: Martin Albrecht
> > _pgp: http://pgp.mit.edu:11371/pks/lookup?op=get&search=0x8EF0DC99
> > _www: 
> > http://www.informatik.uni-bremen.de/~malb<http://www.informatik.uni-bremen.de/%7Emalb>
> > _jab: [EMAIL PROTECTED]
> >
> >
> > >
> >
>
> >
>

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[sage-devel] Re: patch for SymPy <--> SAGE conversion, please review

[David Roe]

Addition not commuting there bothers me.  I can see why it's happening: a
SymPy object doesn't call into the coercion system.  One possible solution
is to have coercion map sage objects into sympy, so both s+o and o+s (in
line 134 and 135 of test_sympy.py) would be SymPy objects.  Is SymPy and the
SymbolicRing canonically isomorphic?  Can every SymbolicRing element be cast
into SymPy?
David

On Nov 25, 2007 9:13 PM, Ondrej Certik <[EMAIL PROTECTED]> wrote:

>
> Hi,
>
> I fixed my bad patch, now it passes all tests in 2.8.14:
>
> http://sagetrac.org/sage_trac/ticket/1189
>
> the main patch (also linked from the ticket) in text form browsable over
> web:
>
> http://sagetrac.org/sage_trac/attachment/ticket/1189/sympy2.patch
>
> Could someone familiar with coerce.pyx review it please? It's actually
> a very simple patch, but it could possibly cause troubles later
> (mabshoff knows:).
>
> Thanks a lot,
> Ondrej
>
> >
>

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[sage-devel] Re: patch for SymPy <--> SAGE conversion, please review

[David Roe]

> I don't think so, since probably sage/maxima have special functions
> sympy doesn't.  And even if it could be, the functions provided by
> SymPy are different
> than the ones provided by SymbolicRing.
>
> If sympy('x') + x and x + sympy('x') are totally different in Sage I
> will be unhappy about
> that.Either the result has to always be in SymPy or always in Sage
> or we have to get
> an error and request that the user explicitly do a coercion.
>
> We have to decide on a canonical map in exactly one direction, and I
> prefer
>
>SymPy ---> SymbolicRing,
>
> just because SymbolicRing is more native in Sage, and probably could be
> improved
> so it would support any SymPy expression (yes -- I know this isn't
> true now, unfortunately).


I would prefer that direction too.  In order to make that happen, the SymPy
__add__ function has to recognize a sage element and call its __add__ method
instead.  This sounds like it should be doable.


> Now that I read through #1189 patch, I'm uncomfortable with
>
>   return _verify_canonical_coercion_c(x,y)
>
> The function _verify_canonical_coercion_c is supposed to be like
>
>   assert(parent(x) is parent(y))
>
> it's *never* supposed to be called when the parents are different -- if it
> is,
> that means there is a bug.  However, you're using it to test whether the
> parents are different, and if so do some other behavior (i.e., eventually
> raise
> a TypeError).   So that makes me nervous.  It would be better to just
> directly do a call to the have_same_parent function, like in the
> implementation
> of _verify_canonical_coercion_c in coerce.pxi.



Agreed.
David

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[sage-devel] Re: Breaking News: Trophees du Libre

[David Joyner]

Wow - think is fantastic!
Thanks very much for preparing slides and presenting SAGE so well.
William: Can we add something to the SAGE website about this?


There is this quote from Stallman on their webpage:

" With 113 participants from 18 countries, 'Trophées du Libre' is
unquestionably the largest competition ever organised to promote the
spirit of Free Software to software users. The developers who will win
this award will get the publicity they deserve."

Richard M Stallman, chairman of the jury of the first Trophées du libre
http://www.tropheesdulibre.org/?lang=en

Here's to hoping SAGE will get lots of good and well-deserved publicity.



On Nov 29, 2007 2:07 PM, Martin Albrecht <[EMAIL PROTECTED]> wrote:
>
> ... we won!
>
> Cheers,
> Martin
> --
> name: Martin Albrecht
> _pgp: http://pgp.mit.edu:11371/pks/lookup?op=get&search=0x8EF0DC99
> _www: http://www.informatik.uni-bremen.de/~malb
> _jab: [EMAIL PROTECTED]
>
>
> >
>

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[sage-devel] Re: windows

[David Harvey]

On Nov 29, 2007, at 4:48 PM, mabshoff wrote:

>
> Ok, I started fleshing out the windows port page at
>
>http://wiki.sagemath.org/windows
>
> Please add content and/or comments, we need to get this going. A data
> point: Maxima 5.13 was downloaded about 40,000 times for Windows since
> the release in August while Linux downloads in that time frame are
> less than 2,500. Maxima on Linux certainly has more distribution
> channels like Linux distribution, but unless you live in Debian
> unstable or some other very current distribution chances are you are
> not running 5.13. Source downloads total about 4,000, so the binary
> Windows download share is *huge* either way and we really need to get
> on the Windows desktop.

So, hypothetically speaking, if I wanted to help with windows  
development, what are my options for getting windows running on my  
macbook?

david


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[sage-devel] Re: windows

[David Harvey]

On Nov 29, 2007, at 5:41 PM, mabshoff wrote:

>> So, hypothetically speaking, if I wanted to help with windows
>> development, what are my options for getting windows running on my
>> macbook?
>>
>
> With bootcamp you can install Windows in a separate partition. VMWare
> Fusion lets you virtualize it (there is a free VMWare player, not sure
> if it exists for Windows), Parallels is quite nice also, but also
> costs some money. You need a windows license to install Windows
> itself.

So I would need to upgrade to 10.5.x ($$), and buy a copy of windows  
($$), if I wanted to do this legally. That's quite a hurdle.

> Another option is to use telnet and/or ssh to log into a Windows box
> remotely. There are also various other protocols to access Windows on
> a framebuffer level. It might be a good idea in the long term to set
> up a box at U Washington to have a homogeneous development environment
> and so on.

If this can be done, that could be a great help.

I do have access to my wife's windows machine, but it has a habit of  
freezing fairly regularly, and to be honest I don't enjoy using it  
very much.

david


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[sage-devel] Re: Sage equivalents for Maple number theory functions

[David Roe]

Excellent list!  Maybe I should take a break from p-adics and do some of
these.  Some of the gaps should be quite easy to fill in.
David

On Nov 30, 2007 12:45 PM, Stephen Forrest <[EMAIL PROTECTED]> wrote:

>
> Hello all,
>
> I've lurked on this list for a time, commenting little because I am
> not yet familiar with Sage.  Some time ago on this list, there was
> some discussion of what number-theoretic functionality Maple
> has that Sage still lacks.
>
> Since I have a substantial background in Maple, as a exercise in
> learning Sage I have compiled a list of number-theoretic
> Maple functions along with any Sage equivalent that is available.  The
> results are available here:
>
> http://wandership.ca/projects/sage/numtheory-SAGE.html
>
> Any questions, corrections, or other comments are welcome.
>
> regards,
>
> Steve
>
> >
>

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[sage-devel] Re: Tutorial to translate in french

[David Joyner]

The "tutorial" and "constructions" links on
http://www.sagemath.org/documentation.html
are what you want.


On Dec 2, 2007 12:41 PM, Philippe Saade <[EMAIL PROTECTED]> wrote:
>
> hi all,
>
> as I said last week, I am willing to give a little help for the usage
> of SAGE in french educational system. One thing that showed to be
> important was the availability of a tutorial in french.
>
> I would appreciate some experts on that list (;-) to point me to an
> existing tutorial in English, to start with. Maybe there is an
> official tutorial.
>
> My public is not composed of researchers but of students, so i don't
> need stuff to explore Elliptic curves and Taniyama-Weil ;-)
>
> Thanks for your help !!
>
> Philippe Saadé
>
> >
>

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[sage-devel] Re: Raising matrices to a power

[David Harvey]

On Dec 3, 2007, at 8:40 AM, Bill Hart wrote:

> I've just been looking at SAGE ticket number 173:
>
> http://www.sagemath.org:9002/sage_trac/ticket/173
>
> The idea is that Mathematica raises a 3 dimensional matrix M over QQ
> to the power 20,000 much faster than either SAGE or Magma.
>
> I don't know any algorithm for doing this efficiently. I only know one
> algorithm:
>
> 1) Compute the  characteristic polynomial p(x) of M (time 0.00s)
> 2) Compute x^2 mod p (time 0.22s)
> 3) Substitute M into the result (time 0.00s)
>
> It's pretty obvious where the time is going here - polynomial
> arithmetic. I guess this is the algorithm being used. Is Pari or NTL
> being used for the polynomial expmod?
>
> I reckon we can speed this up. What do people think?

I would have guessed the algorithm was just "compute M^2 using  
repeated squaring". But your suggestion is quite interesting.

Maybe first check that mathematica is getting the right answer, and  
not some stupid floating point approximation or something.

david


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[sage-devel] Re: Raising matrices to a power

[David Harvey]

On Dec 3, 2007, at 11:20 AM, William Stein wrote:

>
> On Dec 3, 2007 8:13 AM, Bill Hart <[EMAIL PROTECTED]> wrote:
>> I did try to check that Mathematica was getting the right answer, but
>> I had no luck. I don't know how to convert a mathematica matrix into
>> ordinary matrix form in SAGE, so when I do the comparison it always
>> just says false.
>
> Damn it -- you're right.  This isn't the first time I've been  
> bitten by
> this.  Mathematica is just doing the componentwise product!

Ha ha ha ha ha.

That would do it.

We should have done that for polynomial multiplication too, that  
would be way faster.

david


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[sage-devel] Re: Java3D usable in any form?

[David Joyner]

On Dec 3, 2007 7:21 PM, Nils Bruin <[EMAIL PROTECTED]> wrote:
>
> Concerning interactive 3d vis tools:
>
> Is there currently *any* way of getting Java3D to work reliably
> together with sage on, say Mac G5 systems running OSX and on i386/
> amd64 with linux? It doesn't necessarily have to be from the notebook,
> although that would be preferable. Are instructions for this
> available? Will we have this running well in advance of August 2008?
> Are there other high quality interactive 3D visualisation tools that
> work nicely with Sage and are so easy to install that you can ask the
> average sysadmin to do it?


openmath (a 3d graphics package written in tk/tcl) is included with Maxima.
I don't know what you mean by "high quality". The surface plots are wireframe
I think, and the plot commands will pop up an interactive window.


>
> >
>

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[sage-devel] Re: [sage-support] Re: Weaning

[David Harvey]

On Dec 4, 2007, at 5:09 AM, fwc wrote:

>>> 1)  Taylor series of a rational function.
>>
>>> This works:
>>> sage: cos(x).taylor(x,0,2)
>>
>>> This doesn't:
>>> sage: x/(1+x).taylor(x,0,2)
>>
>>> This is very confusing:
>
>> This is due to the fact that '.' binds tighter than '/'.  For  
>> example,
>> sage: x/(1+x).taylor(x,0,2)
>> x/(x + 1)
>> sage: x/((1+x).taylor(x,0,2))
>> x/(x + 1)
>> sage: (x/(1+x)).taylor(x,0,2)
>> x - x^2
>>
>> In Sage, "(x/(1+x))" creates an object and the you call the taylor()
>> method on that object.
>
> Mathematica has the advantage that Series creates a truncated series
> object rather than a polynomial.  Thus it doesn't matter whether the
> division is done before or after:
>
> sage: mathematica("x/Series[1+x, {x, 0, 1}]")
> SeriesData[x, 0, {1, -1}, 1, 3, 1]
> sage: mathematica("Series[x/(1+x), {x, 0, 2}]")
> SeriesData[x, 0, {1, -1}, 1, 3, 1]

H this is an excellent point. We do have a PowerSeriesRing which  
can keep track of where you truncated to, but it's only used in a  
more strictly algebraic setting, it's not really part of the symbolic  
calculus package. Is it possible for the symbolic calculus package to  
do something similar to this? What about creating a PowerSeriesRing  
with the SymbolicExpressionRing as the base ring?


sage: R. = PowerSeriesRing(SymbolicExpressionRing)
 
---
 Traceback (most recent call  
last)

/Users/david/ in ()

/Users/david/sage-2.8.14/local/lib/python2.5/site-packages/sage/rings/ 
power_series_ring.py in PowerSeriesRing(base_ring, name,  
default_prec, names, sparse)
 171 R = PowerSeriesRing_generic(base_ring, name,  
default_prec, sparse=sparse)
 172     else:
--> 173 raise TypeError, "base_ring must be a commutative ring"
 174 _cache[key] = weakref.ref(R)
 175 return R

: base_ring must be a commutative ring


Well maybe not

Would be nice though

david


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[sage-devel] Re: soon everyday will be a Sage day

[David Harvey]

Yeah, I would be much more inclined to spend hours writing doctests  
if I knew there were like ten other people doing so at the same time.

david

On Dec 6, 2007, at 10:40 AM, Martin Albrecht wrote:

>
> Hi there,
>
> some quick idea such that Sage dominates our lives even more:
>
> 1. We should have "Doc Days" (*) in addition to "Bug Days". For  
> these sessions
> we would focus on (a) finding new bugs by (b) writing doctests.  
> Also our Wiki
> might need some care and the manuals always need updates.
>
> 2. Also, a "Busfactor/Code-Review Day" might be a good idea. There  
> are areas
> in the Sage codebase where basically only one developer feels  
> comfortable
> poking around. This is usually not because of scary math only one  
> person
> cares about but because nobody else every sat down and read the  
> code. A "Bus
> Day" (y'know what if that developer gets run-over by a bus) would  
> basically
> mean that we sit down and read chunks of code by other developers.  
> If we are
> stuck the authors are right there on IRC to discuss the random  
> questions we
> come up with. The coercion model, libSingular and cremona.spkg are  
> examples
> for this kind of code in my mind. This would also mean that we  
> review the
> code which is a very very nice thing to have.
>
> (*) William just indicated on IRC that we should probably move away  
> from the
> idea of a whole day to devote to bugs and stuff. Instead a Sage
> Morning/Evening (depending on your favourite timezone) might allow  
> more
> people to participate. E.g. weekends are usually a bad choice for me.
>
> Thoughts?
>
> Martin


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[sage-devel] Re: quo_rem, __floordiv__, and polynomials

[David Harvey]

On Dec 7, 2007, at 10:45 AM, Nick Alexander wrote:

>
>> If the divisor is monic, then everything is okay, but if the divisor
>> is not monic, it's not clear what the remainder should be. I took the
>> agnostic option for the moment.
>
> Why not make it agree with Magma's multivariate definition (used in
> their Euclidean ring Groebner basis calculations)?
>
> The reference is
>
> http://magma.maths.usyd.edu.au/magma/htmlhelp/text1115.htm#11136
>
> I can elaborate.  For what it's worth, I have implemented some of
> this in a .sage file but I couldn't make it very general -- the
> polynomial hierarchy is hard to comprehend these days.

Ok but if you do this, you need to implement it by hand, since  
NTL (the underlying implementation for most of  
Polynomial_integer_dense) isn't able to do this, as far as I know.

david


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[sage-devel] Re: quo_rem, __floordiv__, and polynomials

[David Harvey]

On Dec 7, 2007, at 8:48 AM, Joel B. Mohler wrote:

>
> Hi,
>
> Here's a couple of questions that have occurred to me as I tried to  
> make
> fraction fields of mpolynomials tolerable to work with.
>
> 1) In the "reduce" method in the file fraction_field_element.py  
> (line 72), we
> call quo_rem to divide the gcd out of the numerator and  
> denominator.  Now, by
> definition the remainder should be 0 so we throw out the  
> remainder.  However, it
> seems to me that it should be faster to give the base_ring the  
> information that
> we don't care about the remainder by using the "//" operator (which  
> calls
> __floordiv__).
>
> 2) Ok, so I think #1 is obviously correct and I tried it to see if  
> it made a
> speed difference.  It did, but the wrong way -- __floordiv__ is  
> slow for
> polynomial_integer_dense_ntl.pyx and the docstring explains that we  
> don't know
> how this is defined.  I'm not sure what David Harvey's exact  
> questions are, but
> I think we should get it figured out.  An obvious fact that I'd  
> believe should
> hold is that:
> f.quo_rem(g)[0] == f//g
> That seems to remove any ambiguity.

I should mention that code is only several days old; it's the result  
of a bug-fix from the most recent bug days; it used to segfault on  
e.g. division by zero or division by a non-monic polynomial that  
didn't happen to be an exact divisor.

If the divisor is monic, then everything is okay, but if the divisor  
is not monic, it's not clear what the remainder should be. I took the  
agnostic option for the moment.

(BTW something that still needs to be fixed is that the code won't  
work if the leading coefficient is -1, which should work.)

david


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[sage-devel] Re: having authors names in .py files

[David Joyner]

On Dec 7, 2007 9:50 AM, Ondrej Certik <[EMAIL PROTECTED]> wrote:
>
> On Dec 7, 2007 1:32 PM, David Joyner <[EMAIL PROTECTED]> wrote:
> >
> > I am certainly happy to share credit with anyone on any file I work on.
> > IMHO, anyone who does anything non-trivial has the write to put their
> > name on a xyz.py file, at least if they are happy to cede their copyright to
> > William Stein. In fact, for licensing issues, I would think it is useful to 
> > know
> > who worked on which files.
> > If the concern is that it is hogging docstring real estate, then maybe
> > a new xyz.history file could be created which would have all this info in 
> > it?
>
> I think the idea of the OSS book (and also mine) is to use the
> Mercurial revision history for tracking who wrote each line.
> It's the psychology, for example when I modified the calculus.py, by
> adding a new function and a few lines, I don't feel I should add
> myself at the top of the file. When another 15 people like me are
> going to modify calculus.py, the authors will be quite misleading. The
> Mercurial nevertheless provides exact history who wrote what.


I'm not an expert on mercurial, but I assumed that mercurial
revision history is available to people using sage.math. What if
Joe Shmoe decides to redistribute SAGE on
www.cool-free-math-software.com? Will his version of SAGE also see
who contributed to what? I personally would like to see this information
in the distribution but maybe no one else does.


>
> Ondrej
>
>
> >
>

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[sage-devel] Re: having authors names in .py files

[David Joyner]

I am certainly happy to share credit with anyone on any file I work on.
IMHO, anyone who does anything non-trivial has the write to put their
name on a xyz.py file, at least if they are happy to cede their copyright to
William Stein. In fact, for licensing issues, I would think it is useful to know
who worked on which files.
If the concern is that it is hogging docstring real estate, then maybe
a new xyz.history file could be created which would have all this info in it?



On Dec 7, 2007 6:26 AM, Martin Albrecht <[EMAIL PROTECTED]> wrote:
>
> Also, I would add that these names are usually poorly maintained (at least for
> Sage) partly due to "the awkward question of how much work one must do to get
> one's own name listed there".
>
> Martin
>
>
> --
> name: Martin Albrecht
> _pgp: http://pgp.mit.edu:11371/pks/lookup?op=get&search=0x8EF0DC99
> _www: http://www.informatik.uni-bremen.de/~malb
> _jab: [EMAIL PROTECTED]
>
>
>
> >
>

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[sage-devel] Re: more SAGE publicity :-)

[David Joyner]

On Dec 7, 2007 4:02 PM, William Stein <[EMAIL PROTECTED]> wrote:
>
> On Dec 7, 2007 12:58 PM, John Cremona <[EMAIL PROTECTED]> wrote:
> >
> >
> > On 07/12/2007, William Stein <[EMAIL PROTECTED]> wrote:
> > >
> > > On Dec 7, 2007 11:29 AM, Iftikhar Burhanuddin <[EMAIL PROTECTED]> wrote:
> > > >
> > > > On Fri, 7 Dec 2007, Yi Qiang wrote:
> > > > > http://blog.wired.com/monkeybites/2007/12/math-geek-softw.html
> > > > >
> > > > > "A movement is afoot among some mathematicians in academia to make the
> > > > > switch from expensive, closed-source calculation software to free,
> > > > > open-source alternatives."
> > > >
> > > > Pretty cool.
> > > >
> > > > There should a wiki page which documents mention of SAGE in research
> > > > (articles, books, etc.) and the media (newspapers, popular blogs).
> > >
> > > See
> > >
> > >  http://sagemath.org/why.html
> > >
> >
> > And also the similar page (where?) containing a list of mathematical
> > research papers which menion Sage -- to which I think there will
> > shortly be a new addition by David Harvey.
> >
> > [And while looking for taht page using the Sage search engine I
> > discovered a paper by David Joyner which refers to a paper of my
> > student Steve Wesemeyer -- small world!]
>
> That's here:
>
> http://sagemath.org/pub.html
>
> It really should be moved to a wiki!
>
> Could someone volunteer right now to move it to the wiki?


I volunteer, but if someone to do it, I won't be disappointed!


>
> William
>
>
> >
>

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[sage-devel] Re: Please review letter to Python GHOP

[David Harvey]

typos:

On Dec 7, 2007, at 11:01 PM, Timothy Clemans wrote:

> Magma. To achieve this goal in a reasonable about of time the Sage

=> "amount of time"

> the direction of William Stein, lead developer of Sage, 24 talented
> high school used Sage via the notebook in a computer lab to explore

=> "high school students"

david


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[sage-devel] Re: Fwd: Parallelism in Sage [and MAGNUS]

[David Joyner]

I have written a few people (including Gilbert) about the
possibility of interfacing with MAGNUS. The problem
appears to be that MAGNUS is a gui interface and a
command-line back-end, but the gui is not as
modular as one would like. I hope I'm wrong and would be very
happy to be corrected, but it appears that more work is
needed to get a nice command-line version of MAGNUS.
Once that is finished, it would be straight-forward to
interface with SAGE.

On Dec 9, 2007 2:49 AM, William Stein <[EMAIL PROTECTED]> wrote:
>
> -- Forwarded message --
> From:  <[EMAIL PROTECTED]>
> Date: Dec 8, 2007 6:52 PM
> Subject: Parallelism in Sage
> To: Willaim Stein <[EMAIL PROTECTED]>, Gilbert Baumslag
> <[EMAIL PROTECTED]>
> Cc: [EMAIL PROTECTED]
>
>
> William,
>
> I'm listening to your talk at:
> 
>
> You make the comment about needing (any and all) parallelism in Sage.
>
> Gilbert Baumslag is a distinguished professor at City College in New York
> and is the person behind the CAISS project. See
> 
>
> Gilbert has designed and built a program called Magnus,
> a specialized software package in Infinite Group Theory. I'm one
> of the developers at .
>
> Infinite Group Theory has the property that there are very few algorithms
> (which are guaranteed to terminate). Most of the known attacks on the
> groups are procedures (which may not terminate).
>
> Gilbert has invented a way to think about running these procedures in
> parallel which is a useful paradigm called a "zero-learning curve interface".
>
> Consider your browser as a lab desktop. Consider the problem you are
> trying to solve as a "rock" (an infinite group given by a finite
> presentation). Consider each of the procedures you might want to try
> as a "reagent" that you can apply to the "rock" which will give you
> some property. When computing a property that has multiple procedures
> available you can choose to run any or all of the procedures, give
> percentage of CPU to devote to each, and "poison" parallel procedures
> if and when an answer is found.
>
> The zero learning curve interface is an attempt to make it easy for
> anyone to attack infinite group theory problems with minimal training.
>
> I believe it would be worth your time to at least look at this paradigm
> as it exists in Magnus. I think it would help shape your thoughts on
> doing some kinds of parallel work in Sage.
>
> Tim Daly
>
>
>
>
> --
> William Stein
> Associate Professor of Mathematics
> University of Washington
> http://wstein.org
>
> >
>

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[sage-devel] Re: Fwd: SAGE

[David Joyner]

On rare occasions the GAP support list gets an email from someone with
a slow internet connection (usually from a 3rd world country) who wants
to use GAP. I think everyone would agree that it is important to support
mathematicians in poorer countries and someone mails out a CD or DVD.
In this case, I don't know where Walden U is but I don't think the situation
is the same. I note he didn't say he did not have a fast enough connection, so
it isn't clear to me why he cannot burn his own.


On Dec 9, 2007 8:16 PM, William Stein <[EMAIL PROTECTED]> wrote:
>
> Thoughts?
>
>
> -- Forwarded message --
> From: personal info deleted
> Date: Dec 9, 2007 4:20 PM
> Subject: SAGE
> To: [EMAIL PROTECTED]
>
>
> Dr. Stein:
>
> I find information on SAGE almost "thrilling," and want to get SAGE
> introduced here at Walden University. I am sorry that I'll be overseas
> during the time of the joint meeting of the American Mathematical
> Society and the Mathematical Association of America. Is there any way
> that I can obtain one of the CDs that will be handed out at the
> meeting? I see that it can be downloaded at www.sagemath.org, but feel
> that I can make more impact with a CD in my hand.
>
> Sincerely,
> ...
>
>
>
>
> --
> William Stein
> Associate Professor of Mathematics
> University of Washington
> http://wstein.org
>
> >
>

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[sage-devel] Re: Fwd: SAGE

[David Joyner]

On Dec 9, 2007 8:37 PM, William Stein <[EMAIL PROTECTED]> wrote:
>
> On Dec 9, 2007 5:32 PM, David Joyner <[EMAIL PROTECTED]> wrote:
> > On rare occasions the GAP support list gets an email from someone with
> > a slow internet connection (usually from a 3rd world country) who wants
> > to use GAP. I think everyone would agree that it is important to support
> > mathematicians in poorer countries and someone mails out a CD or DVD.
> > In this case, I don't know where Walden U is but I don't think the situation
> > is the same. I note he didn't say he did not have a fast enough connection, 
> > so
> > it isn't clear to me why he cannot burn his own.
>
> I'm guessing he wants something that looks professionally labeled and
> maybe shrink-wrapped.   What do you think?


That or maybe he thinks he can run SAGE from the CD, as in a live CD.
(A colleague here thought that...)


>
> I could actually have some DVD's professionally printed up (it cost < $5/per)
> and shrink wrapped with printouts of the tutorial, and "sell" the combination
> for $19.99/each...  but that would lead me down a road I really don't want
> to go down.

>
>  -- William
>
>
> >
> >
> >
> > On Dec 9, 2007 8:16 PM, William Stein <[EMAIL PROTECTED]> wrote:
> > >
> > > Thoughts?
> > >
> > >
> > > -- Forwarded message --
> > > From: personal info deleted
> > > Date: Dec 9, 2007 4:20 PM
> > > Subject: SAGE
> > > To: [EMAIL PROTECTED]
> > >
> > >
> > > Dr. Stein:
> > >
> > > I find information on SAGE almost "thrilling," and want to get SAGE
> > > introduced here at Walden University. I am sorry that I'll be overseas
> > > during the time of the joint meeting of the American Mathematical
> > > Society and the Mathematical Association of America. Is there any way
> > > that I can obtain one of the CDs that will be handed out at the
> > > meeting? I see that it can be downloaded at www.sagemath.org, but feel
> > > that I can make more impact with a CD in my hand.
> > >
> > > Sincerely,
> > > ...
> > >
> > >
> > >
> > >
> > > --
> > > William Stein
> > > Associate Professor of Mathematics
> > > University of Washington
> > > http://wstein.org
> > >
> > > >
> > >
> >
> > >
> >
>
>
>
> --
> William Stein
> Associate Professor of Mathematics
> University of Washington
> http://wstein.org
>
> >
>

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[sage-devel] Vega

[David Vevar]

Dear all,

After consulting with professors Stein and Pisanski I'm taking this
opportunity to draw your attention to project Vega (http://vega.ijp.si/
Htmldoc/vinfo.htm).

Vega is a project lead by prof. Pisanski at Institute for Mathematics,
Physics and Mechanics (IMFM: http://www.ijp.si/) in Ljubljana,
Slovenia. It takes a form of Mathematica package (incl. external
programs) specializing mostly but not exclusively in Graph theory.

Unfortunately, after a vibrant start in the (early) nineties, Vega
lost most of its momentum. Having once participated in the project,
and therefore being confident that, in spite of its temporary
inactivity, Vega still has a great potential, I suggest that the SAGE
team explore the possibility of including
(incorporating) it into SAGE. I believe both parties could benefit:
Vega could gain momentum again and, at the same time, make a
significant contribution to SAGE. Maybe for a start, after cleaning
up, it could be bundled with SAGE in it's original Mathematica form
and later gradually rewritten in sage/python.

The latest version can be downloaded here: http://vega.ijp.si/latest.zip.
It contains only Mathematica sources, though. External programs,
written in C(++) and Pascal, are currently distributed only in binary
form (still MSDOS executables, I'm afraid) but I think obtaining their
sources can be arranged. In fact I know it can, since prof. Pisanski
offered his help:

"If there is anything that we at IMFM could do, please let me know. I
can try and get a group of younger colleagues and graduate students
who can help as well.

I would be very glad if Sage would incorporate a system for dealing
with combinatorial and geometric configurations, with maps on surfaces
and with abstract polytopes."

Best regards,
David

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[sage-devel] Re: Fwd: blog and rss

[David Joyner]

On Dec 10, 2007 4:07 PM, Yi Qiang <[EMAIL PROTECTED]> wrote:
>
> I would say that unless you are really serious about blogging, using
> hosted blogging is even easier. Try blogspot
> (http://www.blogspot.com).


Agreed. It's owned by google, so from a gmail account you can just click "more"
in the upper left of the window and select "blogger" from the pop-down menu.


>
> As for setting up planet.sagemath.org, I tried to set it up on
> sage.math.washington.edu last night but ran into this problem:
>
> In [1]: import bsddb
> ---
>Traceback (most recent call last)
>
> /home/yqiang/ in ()
>
> /home/was/s/local/lib/python2.5/bsddb/__init__.py in ()
>  49 from bsddb3.dbutils import DeadlockWrap as _DeadlockWrap
>  50 else:
> ---> 51 import _bsddb
>  52 from bsddb.dbutils import DeadlockWrap as _DeadlockWrap
>  53 except ImportError:
>
> : libdb-4.1.so: cannot open shared
> object file: No such file or directory
>
>
> The planetplanet software requires the bsddb module.  Maybe someone
> with more knowledge can resolve that issue on
> sage.math.washington.edu.
>
>
> On Dec 10, 2007 12:53 PM, Bobby Moretti <[EMAIL PROTECTED]> wrote:
> >
> > I think there are two steps:
> >
> > 1) start a blog - wordpress is frickin' easy to set up. For that, you'd go 
> > to
> >
> > http://wordpress.org/download/
> >
> > - grab the software, untar, set up apache to serve the directory (so
> > perhaps you would want something like http://wstein.org/blog)
> >
> > - pt-get install mysql and php.
> >
> > - follow the instructions here:
> > http://codex.wordpress.org/Installing_WordPress#Famous_5-Minute_Install
> >
> > 2) set up planet.sagemath.org
> >
> > - I'm not so knowledgeable about this one, but the instructions look
> > pretty straightforward, and it's written in python.
> >
> > On Dec 10, 2007 12:18 PM, William Stein <[EMAIL PROTECTED]> wrote:
> > >
> > > On Dec 10, 2007 12:15 PM, Ondrej Certik <[EMAIL PROTECTED]> wrote:
> > > >
> > > > On Dec 10, 2007 8:07 PM, Bobby Moretti <[EMAIL PROTECTED]> wrote:
> > > > >
> > > > > Very cool. Now I just need to find time to blog! :)
> > > >
> > > > And that's exactly the point of the planet, you don't have to find
> > > > time to blog regularly. If there are enough people on it, and if the
> > > > atmosphere is that they mark by "sage" only post about Sage and not
> > > > some stupid things, then planet always contains some interesting info,
> > > > and it's really cool to read it as a user.
> > > >
> > >
> > > Hi,
> > >
> > > Could somebody post trivial steps so I can -- in a manner of moments -- go
> > > from somebody who has never written a blog post to somebody who is
> > > writing a blog post that appears on some sort of "Planet Sage"?  I'm sure
> > > I could write a little something about the slashdotting this weekend,
> > > status of sage,
> > > etc  I bet there are a few other people out there "in the audience" 
> > > that
> > > would similarly like to follow such directions.
> > >
> > >  -- Willam
> > >
> > >
> > > >
> > >
> >
> >
> >
> > --
> > Bobby Moretti
> > [EMAIL PROTECTED]
> >
> > >
> >
>
> >
>

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[sage-devel] Re: more SAGE publicity [new wiki items]

[David Joyner]

On Dec 7, 2007 4:50 PM, David Joyner <[EMAIL PROTECTED]> wrote:
> On Dec 7, 2007 4:02 PM, William Stein <[EMAIL PROTECTED]> wrote:
> >
> > On Dec 7, 2007 12:58 PM, John Cremona <[EMAIL PROTECTED]> wrote:
> > >
> > >
> > > On 07/12/2007, William Stein <[EMAIL PROTECTED]> wrote:
> > > >
> > > > On Dec 7, 2007 11:29 AM, Iftikhar Burhanuddin <[EMAIL PROTECTED]> wrote:
> > > > >
> > > > > On Fri, 7 Dec 2007, Yi Qiang wrote:
> > > > > > http://blog.wired.com/monkeybites/2007/12/math-geek-softw.html
> > > > > >
> > > > > > "A movement is afoot among some mathematicians in academia to make 
> > > > > > the
> > > > > > switch from expensive, closed-source calculation software to free,
> > > > > > open-source alternatives."
> > > > >
> > > > > Pretty cool.
> > > > >
> > > > > There should a wiki page which documents mention of SAGE in research
> > > > > (articles, books, etc.) and the media (newspapers, popular blogs).
> > > >
> > > > See
> > > >
> > > >  http://sagemath.org/why.html
> > > >
> > >
> > > And also the similar page (where?) containing a list of mathematical
> > > research papers which menion Sage -- to which I think there will
> > > shortly be a new addition by David Harvey.
> > >
> > > [And while looking for taht page using the Sage search engine I
> > > discovered a paper by David Joyner which refers to a paper of my
> > > student Steve Wesemeyer -- small world!]
> >
> > That's here:
> >
> > http://sagemath.org/pub.html
> >
> > It really should be moved to a wiki!
> >
> > Could someone volunteer right now to move it to the wiki?
>
>

I volunteer, but if someone else wants to do it, I won't be disappointed!

>

I have added now
http://wiki.sagemath.org/SAGE_in_the_News
and
http://wiki.sagemath.org/Publications_using_SAGE
and
http://wiki.sagemath.org/Teaching_with_SAGE
More items need to be added but I wanted to tell people in case others
wanted to work on any of them.

>
>
> >
> > William
> >
> >
> > > >
> >
>

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[sage-devel] Re: pyglet for 3D graphics

[David Joyner]

On Dec 10, 2007 4:58 PM, William Stein <[EMAIL PROTECTED]> wrote:
>
> On Dec 10, 2007 1:39 PM, David Joyner <[EMAIL PROTECTED]> wrote:
> >
> > The plots look really nice. Thanks for posting this.
> > Since pyglet depends on it, I'm curious what people think of opengl.
>
> Try this in Sage right now.  It might work for you.
>
> (1) From the command line, type
>
> sage -sh
>
> (2) Type
>
>bash$pythonw


"pythonw" gave "command not found". If you meant "python", I got a
segfault:


[EMAIL PROTECTED]:/mnt/drive_hda1/sagefiles/sage-2.8.13.alpha1$ python
Python 2.5.1 (r251:54863, Nov 26 2007, 13:44:20)
[GCC 4.1.3 20070929 (prerelease) (Ubuntu 4.1.2-16ubuntu2)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> from sympy import symbols, Plot
>>> x,y,z = symbols('xyz')
>>> Plot(x*y**3-y*x**3)
[0]: x*y**3 - y*x**3, 'mode=cartesian'
>>> Window initialization failed: No conforming visual exists
Segmentation fault (core dumped)


This is on an ubuntu 64 bit machine.

>
> (3) paste the following code into your python session:
>
> from sympy import symbols, Plot
> x,y,z = symbols('xyz')
> Plot(x*y**3-y*x**3)
>
> I just tried this and got a very nice dynamically rotateable 3d plot.
> Very nice.
>
>
>  -- William
>
>
> >
>

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[sage-devel] Re: pyglet for 3D graphics

[David Joyner]

The plots look really nice. Thanks for posting this.
Since pyglet depends on it, I'm curious what people think of opengl.


On Dec 10, 2007 4:34 PM, Ondrej Certik <[EMAIL PROTECTED]> wrote:
>
> Hi,
>
> just letting you know about one great project -- pyglet:
>
> http://pyglet.org/
>
> we use it for 3D graphics in SymPy, it is a pure python library, that
> uses ctypes for binding to directx on win, opengl on linux and
> something in mac os x. I am not an expert in 3D,
> I just need something that just works and pyglet is it.
>
> Some examples:
>
> http://code.google.com/p/sympy/wiki/PlottingModule
>
> and you can find a lot of examples on the pyglet webpage.
>
> I am not sure it can be useful for Sage, since Sage is using the
> notebook (mostly), but still it's a nice thing that one can finally
> (after so many years) just write a simple Python program
> and it can do 3D things (fast) on all platforms and all in pure Python.
>
> Ondrej
>
> >
>

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[sage-devel] Re: Vega

[David Vevar]

On Dec 10, 8:16 pm, Jason Grout <[EMAIL PROTECTED]> wrote:

> Getting the source code and clarifying the license is probably the next
> step.  The closest I can find to a license while poking around a bit is
> the statement in v5init.m:
>
> (*  *)
> (* This file is part of Vega 0.5*)
> (* Copyright (C) 1991-1997 by IMFM, Ljubljana   *)
> (* Imagine a lengthy GNU Copyright message in this place.   *)
>
> or the statement on the websitehttp://vega.ijp.si/Htmldoc/vinfo.htm:
>
> Project VEGA is maintained by COMOT It is primarily intended for those
> who contribute to it, and is free for scientific and teaching
> non-commercial purposes.

There is a COPYRIGHT.T in vega05/setup/.

Hm. I guess prof. Pisanski (or COMOT: 
http://vega.ijp.si/Htmldoc/people/COMOT.HTM)
will have to grant a special license - most probably GPL. He also
maintains the source.

David
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[sage-devel] Re: Vega

[David Vevar]

On Dec 10, 9:27 pm, mabshoff <[EMAIL PROTECTED]
dortmund.de> wrote:
> > Getting the source code and clarifying the license is probably the next
> > step.  The closest I can find to a license while poking around a bit is
> > the statement in v5init.m:
>
> Yep, that is the most important step. Without proper licensing nobody
> will touch the code.

The license is transcribed from Brendan McKays "Restrictions"
regarding usage of nauty (http://cs.anu.edu.au/~bdm/nauty/) which is
also a part of Vega.
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[sage-devel] Re: Vega

[David Vevar]

On Dec 11, 12:48 am, David Vevar <[EMAIL PROTECTED]> wrote:
> On Dec 10, 9:27 pm, mabshoff <[EMAIL PROTECTED]
>
> dortmund.de> wrote:
> > > Getting the source code and clarifying the license is probably the next
> > > step.  The closest I can find to a license while poking around a bit is
> > > the statement in v5init.m:
>
> > Yep, that is the most important step. Without proper licensing nobody
> > will touch the code.
>
> The license is transcribed from Brendan McKays "Restrictions"
> regarding usage of nauty (http://cs.anu.edu.au/~bdm/nauty/) which is
> also a part of Vega.

Clarifying: nauty is _used_ by Vega in the form of dreadnaut
"interpreter" (DREADNAU.EXE in /vega05/Public/EXE/).
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[sage-devel] Re: bug in 2.8.15 (somewhere in sage.calculus?)

[David Joyner]

On Dec 10, 2007 8:29 PM, Jonathan Bober <[EMAIL PROTECTED]> wrote:
>
> Hi all. I just opened ticket #1457 (see below)
>
> http://trac.sagemath.org/sage_trac/ticket/1457
>
> The following is hopefully pretty self explanatory:
>
> ---
>
> The following took place on an Intel Core Duo (32 bit) running Ubuntu
> 7.10. Hopefully the cause is obvious for someone familiar with the
> calculus/plotting code.
>
> (Note: replacing f(x) with f(x) = 2.0 * sqrt(x^2.0 + 300.0^2.0) - x +
> 1000.0 is a suitable workaround.)
>
>
> --
> | SAGE Version 2.8.15, Release Date: 2007-12-03  |
> | Type notebook() for the GUI, and license() for information.|
> --
>
> sage: f(x) = 2 * sqrt(x^2 + 300^2) - x + 1000
> sage: P = f.diff(x).diff(x).plot(xmin=0,xmax=1000)
> ---
> Traceback (most recent call last)
>

Note

sage: x = var("x")
sage: f = lambda x: 2 * sqrt(x^2 + 300^2) - x + 1000
sage: P = f(x).diff(x).diff(x).plot(xmin=0,xmax=1000)
sage: show(P)
sage: g =  2 * sqrt(x^2 + 300^2) - x + 1000
sage: P = g.diff(x).diff(x).plot(xmin=0,xmax=1000)
sage: show(P)

both work and yield the same plot.


> /home/bober/sage-2.8.15.alpha1/ in ()
>
> /home/bober/sage-2.8.15.alpha1/local/lib/python2.5/site-packages/sage/calculus/calculus.py
>  in plot(self, *args, **kwds)
> 602 else:
> 603 f = self.function(param)
> --> 604 return plot(f, *args, **kwds)
> 605
> 606 def __lt__(self, right):
>
> /home/bober/sage-2.8.15.alpha1/local/lib/python2.5/site-packages/sage/plot/plot.py
>  in __call__(self, funcs, *args, **kwds)
>2303 G = funcs.plot(*args, **kwds)
>2304 else:
> -> 2305 G = self._call(funcs, *args, **kwds)
>2306 if do_show:
>2307 G.show()
>
> /home/bober/sage-2.8.15.alpha1/local/lib/python2.5/site-packages/sage/plot/plot.py
>  in _call(self, funcs, xmin, xmax, parametric, polar, label, show, **kwds)
>2353
>2354 try:
> -> 2355 y = f(x)
>2356 data.append((x, float(y)))
>2357 except (ZeroDivisionError, TypeError, ValueError), msg:
>
> /home/bober/sage-2.8.15.alpha1/local/lib/python2.5/site-packages/sage/calculus/calculus.py
>  in (x)
> 591 else:
> 592 param = A[0]
> --> 593 f = lambda x: self(x)
> 594 else:
> 595 A = self.variables()
>
> /home/bober/sage-2.8.15.alpha1/local/lib/python2.5/site-packages/sage/calculus/calculus.py
>  in __call__(self, *args)
>4012 vars = self.args()
>4013 dct = dict( (vars[i], args[i]) for i in range(len(args)) )
> -> 4014 return self._expr.substitute(dct)
>4015
>4016 def _repr_(self, simplify=True):
>
> /home/bober/sage-2.8.15.alpha1/local/lib/python2.5/site-packages/sage/calculus/calculus.py
>  in substitute(self, in_dict, **kwds)
>2589 kwds = self.__parse_in_dict(in_dict, kwds)
>2590 kwds = self.__varify_kwds(kwds)
> -> 2591 return X._recursive_sub(kwds)
>2592
>2593 def subs(self, *args, **kwds):
>
> /home/bober/sage-2.8.15.alpha1/local/lib/python2.5/site-packages/sage/calculus/calculus.py
>  in _recursive_sub(self, kwds)
>3424 """
>3425 ops = self._operands
> -> 3426 new_ops = [SR(op._recursive_sub(kwds)) for op in ops]
>3427
>3428 #Check to see if all of the new_ops are symbolic constants
>
> /home/bober/sage-2.8.15.alpha1/local/lib/python2.5/site-packages/sage/calculus/calculus.py
>  in _recursive_sub(self, kwds)
>3424 """
>3425 ops = self._operands
> -> 3426 new_ops = [SR(op._recursive_sub(kwds)) for op in ops]
>3427
>3428 #Check to see if all of the new_ops are symbolic constants
>
> /home/bober/sage-2.8.15.alpha1/local/lib/python2.5/site-packages/sage/calculus/calculus.py
>  in _recursive_sub(self, kwds)
>3430 is_constant = all(map(lambda x: isinstance(x, 
> SymbolicConstant), new_ops))
>3431 if is_constant:
> -> 3432 return SymbolicConstant( self._operator(*map(lambda x: 
> x._obj, new_ops)) )
>3433 else:
>3434 return self._operator(*new_ops)
>
> /home/bober/sage-2.8.15.alpha1/rational.pyx in 
> sage.rings.rational.Rational.__pow__()
>
> : BUG:  Rational.__pow__ called on a 
> non-Rational
> sage:
>
>
>
> >
>

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[sage-devel] Re: pyglet for 3D graphics

[David Joyner]

On Dec 10, 2007 9:32 PM, Carl Witty <[EMAIL PROTECTED]> wrote:
>
> On Dec 10, 2:03 pm, "David Joyner" <[EMAIL PROTECTED]> wrote:
> > [EMAIL PROTECTED]:/mnt/drive_hda1/sagefiles/sage-2.8.13.alpha1$ python
> > Python 2.5.1 (r251:54863, Nov 26 2007, 13:44:20)
> > [GCC 4.1.3 20070929 (prerelease) (Ubuntu 4.1.2-16ubuntu2)] on linux2
> > Type "help", "copyright", "credits" or "license" for more information.>>> 
> > from sympy import symbols, Plot
> > >>> x,y,z = symbols('xyz')
> > >>> Plot(x*y**3-y*x**3)
> >
> > [0]: x*y**3 - y*x**3, 'mode=cartesian'>>> Window initialization failed: No 
> > conforming visual exists
> >
> > Segmentation fault (core dumped)
> >
> > This is on an ubuntu 64 bit machine.
>
> I'm guessing this is a combination of poor error checking and strict
> requirements on your OpenGL capabilities.
>
> What is the output of the "glxinfo" command on your machine?


It's a mess to me:-)

[EMAIL PROTECTED]:~$ glxinfo
name of display: :0.0
display: :0  screen: 0
direct rendering: No (If you want to find out why, try setting
LIBGL_DEBUG=verbose)
server glx vendor string: SGI
server glx version string: 1.2
server glx extensions:
GLX_ARB_multisample, GLX_EXT_visual_info, GLX_EXT_visual_rating,
GLX_EXT_import_context, GLX_EXT_texture_from_pixmap, GLX_OML_swap_method,
GLX_SGI_make_current_read, GLX_SGIS_multisample, GLX_SGIX_hyperpipe,
GLX_SGIX_swap_barrier, GLX_SGIX_fbconfig, GLX_MESA_copy_sub_buffer
client glx vendor string: SGI
client glx version string: 1.4
client glx extensions:
GLX_ARB_get_proc_address, GLX_ARB_multisample, GLX_EXT_import_context,
GLX_EXT_visual_info, GLX_EXT_visual_rating, GLX_MESA_allocate_memory,
GLX_MESA_copy_sub_buffer, GLX_MESA_swap_control,
GLX_MESA_swap_frame_usage, GLX_OML_swap_method, GLX_OML_sync_control,
GLX_SGI_make_current_read, GLX_SGI_swap_control, GLX_SGI_video_sync,
GLX_SGIS_multisample, GLX_SGIX_fbconfig, GLX_SGIX_pbuffer,
GLX_SGIX_visual_select_group, GLX_EXT_texture_from_pixmap
GLX version: 1.2
GLX extensions:
GLX_ARB_get_proc_address, GLX_ARB_multisample, GLX_EXT_import_context,
GLX_EXT_visual_info, GLX_EXT_visual_rating, GLX_MESA_copy_sub_buffer,
GLX_OML_swap_method, GLX_SGI_make_current_read, GLX_SGIS_multisample,
GLX_SGIX_fbconfig, GLX_EXT_texture_from_pixmap
OpenGL vendor string: Mesa project: www.mesa3d.org
OpenGL renderer string: Mesa GLX Indirect
OpenGL version string: 1.4 (2.1 Mesa 7.0.1)
OpenGL extensions:
GL_ARB_depth_texture, GL_ARB_draw_buffers, GL_ARB_fragment_program,
GL_ARB_imaging, GL_ARB_multisample, GL_ARB_multitexture,
GL_ARB_occlusion_query, GL_ARB_point_parameters, GL_ARB_point_sprite,
GL_ARB_shadow, GL_ARB_shadow_ambient, GL_ARB_texture_border_clamp,
GL_ARB_texture_compression, GL_ARB_texture_cube_map,
GL_ARB_texture_env_add, GL_ARB_texture_env_combine,
GL_ARB_texture_env_crossbar, GL_ARB_texture_env_dot3,
GL_ARB_texture_mirrored_repeat, GL_ARB_texture_non_power_of_two,
GL_ARB_texture_rectangle, GL_ARB_transpose_matrix, GL_ARB_vertex_program,
GL_ARB_window_pos, GL_EXT_abgr, GL_EXT_bgra, GL_EXT_blend_color,
GL_EXT_blend_equation_separate, GL_EXT_blend_func_separate,
GL_EXT_blend_logic_op, GL_EXT_blend_minmax, GL_EXT_blend_subtract,
GL_EXT_clip_volume_hint, GL_EXT_copy_texture, GL_EXT_draw_range_elements,
GL_EXT_fog_coord, GL_EXT_framebuffer_object, GL_EXT_multi_draw_arrays,
GL_EXT_packed_pixels, GL_EXT_paletted_texture, GL_EXT_point_parameters,
GL_EXT_polygon_offset, GL_EXT_rescale_normal, GL_EXT_secondary_color,
GL_EXT_separate_specular_color, GL_EXT_shadow_funcs,
GL_EXT_shared_texture_palette, GL_EXT_stencil_wrap, GL_EXT_subtexture,
GL_EXT_texture, GL_EXT_texture3D, GL_EXT_texture_edge_clamp,
GL_EXT_texture_env_add, GL_EXT_texture_env_combine,
GL_EXT_texture_env_dot3, GL_EXT_texture_lod_bias,
GL_EXT_texture_mirror_clamp, GL_EXT_texture_object,
GL_EXT_texture_rectangle, GL_EXT_vertex_array, GL_APPLE_packed_pixels,
GL_ATI_draw_buffers, GL_ATI_texture_env_combine3,
GL_ATI_texture_mirror_once, GL_ATIX_texture_env_combine3,
GL_IBM_texture_mirrored_repeat, GL_INGR_blend_func_separate,
GL_MESA_pack_invert, GL_MESA_ycbcr_texture, GL_NV_blend_square,
GL_NV_fragment_program, GL_NV_light_max_exponent, GL_NV_point_sprite,
GL_NV_texgen_reflection, GL_NV_texture_rectangle, GL_NV_vertex_program,
GL_NV_vertex_program1_1, GL_SGI_color_matrix, GL_SGI_color_table,
GL_SGIS_generate_mipmap, GL_SGIS_texture_border_clamp,
GL_SGIS_texture_edge_clamp, GL_SGIS_texture_lod, GL_SGIX_depth_texture,
GL_SGIX_shadow, GL_SGIX_shadow_ambient, GL_SUN_multi_draw_arrays

   visual  x  bf lv rg d st colorbuffer ax dp st accumbuffer  ms  cav
 id d

[sage-devel] since we all really love talking about licensing...

[David Harvey]

Hi guys,

I am writing a library for polynomial arithmetic which I might  
eventually like to see included in Sage. (It is not presently part of  
FLINT, but maybe one day it will be.)

I would like to release it simultaneously under GPL v2 and GPL v3. I  
specifically do not want to use the clause "either version 2 of the  
License, or (at your option) any later version." Basically I don't  
trust the FSF enough at the moment to release my code under GPL v7,  
so I want to stick with the existing licenses.

Small portions of the source code of the library are adapted from  
existing software (NTL and FLINT), both of which are released under  
"version 2, or at your option any later version". It also includes  
some code from GMP 4.2.1, which is released under "LGPL v2.1, or at  
your option any later version".

Two questions:

Q1) Is it legal for me to do this? Am I violating the licenses of  
NTL, FLINT, or GMP? For example, since NTL is released under "version  
2, or at your option any later version", am I violating Shoup's  
copyright by re-releasing part of his code under only v2 and v3?

Q2) If I release under GPL v2 and v3 only, is it possible for Sage to  
use my code?

thanks guys

david


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[sage-devel] Re: using Singular's invariant_ring [new patch submitted]

[David Joyner]

Thank you! After all this, I have finally submitted a patch which adds
this functionality: http://sagetrac.org/sage_trac/ticket/1485
I changed the name as you suggested and slightly edited the example in
the docstring.
The patch now passed sage -t and implements the wrapper we worked on.


On Dec 11, 2007 12:12 PM, Simon King <[EMAIL PROTECTED]> wrote:
> Dear David, dear Martin,
>
> I made the following modifications; see
> http://sage.math.washington.edu/home/SimonKing/patches/matrix_group.py
>
> - Some typos in the doc-string. Reference added.
> - In the bad characteristic case, the result is in general not a minimal
>   generating set. I emphasize this in the doc-string. But then, the name
>   "fundamental_invariants" is misleading (as far as i know, fundamental
>   means minimal). I didn't change it, but i think "generating_invariants"
>   fits better.
>
> - Definition of Lgens: It is simpler to use ','.join and list coercion.
> - It is dangerous to refer to a singular variable name 'L', 'P' or 'S',
>   because it is not unlikely that some user will use the same name.
>   Therefore i introduce ReyName=singular._next_var_name(), similarly
>   PName and SName.
> - The lines
> Rey = singular('L[1]')
> IR = Rey.invariant_algebra_reynolds()
> L = [f for f in IR]
>   mean a lot of traffic through the interface. I tried to keep the things
>   as internal to Singular as possible.
>
> - You use variables x(1),x(2),... for the Singular sub-process, but
>   x1,x2,... for the result. I think it is simpler to use the same names.
>
> @Martin: Is there a more direct way to convert an ideal (or 1xn matrix) of
> the name IRName existing in a Singular sub-process into a list of elements
> of a PolynomialRing PR than the following?
>   return [PR(singular(IRName+'[1,%s]'%n))) for n in \\
>   range(1,1+singular('ncols('+IRName+')'))]
>
> - In the 'bad characteristic', invariant_ring only has two return values,
>   not three. So, it must be
> singular.eval('matrix P,S=invariant_ring(%s)'%Lgens)
>   or better
> singular('matrix %s,%s=invariant_ring(%s)'%(PName,SName,Lgens))
> - IR = singular('P,S') is a list of two matrices, and this is not what we
>   want. I would return a list of polynomials (similar to the case of 'good
>   characteristic'), formed by all polynomials of P and all but the first
>   of S: The first of S always is 1, and i wouldn't count 1 as a
>   sub-algebra generator.
>
> Yours
> Simon
>
>

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[sage-devel] Sparse SVD

[David Roe]

My housemates have been writing a Python wrapper for SVDLIBC (a C library
that does SVDs for sparse and dense matrices over the reals) using Swig.  I
suggested that they use Cython instead and thought that this might make a
good spkg.  I've asked a few people about sparse SVDs, and I think Sage
currently has no mechanism to do this.  Thoughts?  At some point I'll
probably ask for help on IRC in making an spkg since I've only been involved
in writing library code and not at all on the spkg side of things.

The website for SVDLIBC:
http://tedlab.mit.edu/~dr/SVDLIBC/

David

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[sage-devel] Re: DVDs and Posters

[David Joyner]

On Dec 15, 2007 2:40 AM, William Stein <[EMAIL PROTECTED]> wrote:
>
> On Dec 14, 2007 10:12 PM, Jason Grout <[EMAIL PROTECTED]> wrote:
> > As a student, I probably wouldn't buy a DVD if it was $20 and probably
> > would forget about it later and wouldn't download Sage. I probably also
> > wouldn't need a printed version of the tutorial even if I did get the
> > DVD.  I *would* probably buy a DVD, say in a paper slipcase with the
> > tutorial on the DVD, if it was under $5, though.  It would be an
> > absolute no-brainer to buy and try if it was something like $2.
> >
> > *jason jumps up on his soapbox*
> [...]
>
> Here's my brother's response (he owns the shrinkwrapping equipment, etc., we
> would use).  I agree with him.   I think we should give things away, but we
> could have a "tax-deductible donations flier" printed up for when people ask
> about paying (because they want to -- this happens to me all the time).
> This will probably make everyone happy, since they can save on their taxes,
> etc., and help us out all at once.   And the UW website makes it
> easy for people to donate via the web to Sage.


I wonder if you'd want to add a line where if they donate over $X then
they get a SAGE t-shirt mailed to them?



>
> -- Forwarded message --
> From: Dennis Stein <[EMAIL PROTECTED]>
> Date: Dec 14, 2007 11:34 PM
> Subject: Re: [sage-devel] Re: DVDs and Posters
> To: William Stein <[EMAIL PROTECTED]>
>
>
> I've got an idea... since printing the manual and flyers and
> shrinkwrapping cost me almost nothing, let me print 20 of them up just
> for free and then you can do whatever you want with them on the first
> day and decide if you want more of them for the rest of the meeting.
> I think getting the DVDs in as many hands as possible is probably the
> best strategy.  Quantity is very important because in situations like
> this, you never know which seeds may grow, so the more seeds you
> plant, the better.  If you're going to do $2, why not make it free?
> Back in the Hotmail days, I bet growth would have been much slower if
> an account had been $2 instead of free.  Think of passing out the DVDs
> as a marketing expense for the sage project, just like paying for the
> booth, printing up flyers, paying for a keyword search on Google, or
> any other way you get the word out there.   You can probably find a
> vendor in Seattle to print graphics on blank DVDs for you for a pretty
> low cost or I can have them waiting for you in San Diego.
>
>
> >
>

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[sage-devel] Re: trying to define acsc(x), acsch(x) and friends

[David Harvey]

On Dec 17, 2007, at 6:00 AM, Dan Drake wrote:

> Hello,
>
> I'm trying to define inverse csc, sec, and cot and their hyperbolic
> versions. I dug through
> $SAGE_ROOT/devel/sage-main/build/sage/calculus/calculus.py and  
> thought I

Hi Dan,

I'm not sure if the following will solve your problem, but instead of  
editing files under $SAGE_ROOT/devel/sage-main/build/, you should  
edit the files under $SAGE_ROOT/devel/sage-main/sage/calculus/... and  
then run "sage -b" from $SAGE_ROOT before booting up sage again.

david


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[sage-devel] Re: Getting wiki pages into the official documentation

[David Joyner]

I am definitely extremely interested. I'll be able to play around with
it Friday,
but probly not much before that.

On Dec 18, 2007 5:55 PM, mabshoff
<[EMAIL PROTECTED]> wrote:
>
> Hello,
>
> since the FAQ seems to get added content on a regular basis now it
> might be a good idea to include it into the official documentation.
> While looking for something else moinmoin wiki related I came across a
> latex export plugin, see
>
> http://moinmo.in/FormatterMarket/text_latex.py
>
> It looks like a potential solution to our problem. Is anybody out
> there who wants to play around with it? I could install the plugin if
> William thinks that it is a good idea.
>
> Cheers,
>
> Michael
> >
>

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[sage-devel] zn_poly -- request for testing

[David Harvey]

Hi folks,

I've started working on a new C library called "zn_poly", which does  
polynomial arithmetic in (Z/nZ)[x], where n fits into an unsigned  
long. Similar to NTL's zz_pX class. This might eventually be part of  
FLINT, but for now it's a separate project.

I am maintaining a website for zn_poly at

   http://math.harvard.edu/~dmharvey/zn_poly/

I have made an spkg for sage-2.9, you can get it from

   http://math.harvard.edu/~dmharvey/zn_poly/releases/zn_poly-0.4.1.spkg

I don't know if this will build on all sage-supported systems yet. So  
far I have successfully built on:

* sage.math (AMD opteron, debian linux)
* bsd (a xeon I think?)
* my laptop: core 2 duo, mac OS 10.4.10
* my desktop: ppc G5, mac OS 10.4.10
* my very old laptop: ppc G3, mac OS 10.3.9 (zn_poly, but not the spkg)

I'd really appreciate people trying this out on various systems and  
reporting back what happens.

As an application, I rewrote my "frobenius" program, which is  
currently included in Sage via  
sage.schemes.hyperelliptic_curves.frobenius.frobenius. This program  
computes the characteristic polynomial of frobenius (i.e. the zeta  
function) for a hyperelliptic curve over GF(p), where p is relatively  
large.

Here is a patch which upgrades to the new version:

   http://sage.math.washington.edu/home/dmharvey/patches/hypellfrob.hg

The algorithm depends heavily on polynomial arithmetic, often for a  
small (word-sized) modulus. The old version used NTL for the  
polynomial arithmetic (either ZZ_pX or zz_pX). The new version  
attempts to use zn_poly arithmetic where possible. Below are some  
example timings for the new version (on sage.math). It incorporates  
some algorithmic improvements too, but a lot of the speedup is due to  
zn_poly vs NTL.

genus 2
(compute charpoly mod p)

p = 2^16 + 1:  old = 0.068s, new = 0.008s
p = 2^20 + 7:  old = 0.288s, new = 0.044s
p = 2^24 + 43: old = 1.244s, new = 0.324s
p = 2^28 + 3:  old = 5.63s,  new = 2.952s
p = 2^32 + 15: old = 29.0s,  new = 21.6s

genus 3
(compute charpoly mod p)

p = 2^16 + 1:  old = 0.136s, new = 0.020s
p = 2^20 + 7:  old = 0.580s, new = 0.092s
p = 2^24 + 43: old = 2.548s, new = 0.648s
p = 2^28 + 3:  old = 11.4s,  new = 5.9s
p = 2^32 + 15: old = 58.2s,  new = 43.3s

genus 4
(compute charpoly mod p^2)

p = 2^16 + 1:  old = 0.61s, new = 0.16s
p = 2^20 + 7:  old = 5.23s, new = 0.92s
p = 2^24 + 43: old = 25.7s, new = 20.3s
p = 2^28 + 3:  old = 233s,  new = 111s
p = 2^32 + 15: old = 1246s,  new = 1313s

H that last one ain't so great. That's because zn_poly excels  
at small-to-medium polynomials, but isn't so good for large  
polynomials (yet!).

david


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[sage-devel] Re: factoring benchmarks

[David Harvey]

On Dec 19, 2007, at 7:19 PM, Bill Hart wrote:

>
> I get about 7us per loop on sage.math for Pari for the exponentiation.
> So perhaps this is all architecture dependent. This would not surprise
> me in the slightest.
>
> At any rate, I suspect the algorithms used for factorisation are
> implemented quite differently between NTL and Pari. Since both Pari
> and NTL use GMP mpn's for underlying integer arithmetic in SAGE, I
> think the algorithms being used for factorisation are much more
> relevant than the speed of basic arithmetic, which should be the same
> for both.
>
> The other point is that both Pari and NTL use finite field stuff to
> factor polynomials over the integers. So the speed of integer
> arithmetic is almost irrelevant.
>
> Having said all that, it is surprising that NTL is behind Pari for
> polynomial factorisation, given the amount of work Victor put into
> this. Can you try your example problems on sage.math?

On the other hand, Shoup's research is mostly about the asymptotics  
for very large degree problems, so perhaps he didn't bother trying to  
optimise the small polynomial case very much (?)

david


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[sage-devel] Re: traffic to sagemath.org

[David Joyner]

Does Spain in the number 2 position of
"Sagemath.org users come from these countries:"
mean that Spain downloads more copies of SAGE than
any other country but the US? Or i it just webpage
accesses?


On Dec 20, 2007 12:06 PM, William Stein <[EMAIL PROTECTED]> wrote:
>
> Hi Sage Developers,
>
> With help from Martin Albrecht, I've been tracking the traffic to
> sagemath.org here:
>
> http://sagemath.org/traffic.html
>
> Probably the most interesting graph is this one:
>
> http://www.alexa.com/data/details/traffic_details/sagemath.org?site0=sagemath.org&site1=www.maplesoft.com&site2=www.wolfram.com
>
> it compares Sagemath.org to Maplesoft.com up until Dec 17. Before the
> UW press release (inspired by Trophees du Libre ), sagemath.org
> traffic was insignificant when compared to Maple.   On Dec 3 when the
> press release went out until Dec 11, there was a huge spike in
> traffic, so that sagemath.org went from being a speck to over twice
> the amount of traffic as Maple gets.  NOTE -- this increase in traffic
> started two days before the slashdotting.  On Dec 5 during the
> slashdotting, the number of downloads of sage itself went up a huge
> amount (thousands per day).  This hump died down after about a week on
> December 11.  However, the steady state for sagemath.org during the
> last week has been similar to and sometimes slightly hire than
> maplesoft.com.   This suggests that the number of Sage users has gone
> up by quite a bit, and that a nontrivial fraction of the people who
> tried Sage a week ago are now Sage users.   Traffic to sagemath.org
> has gone from "0"  as measured by "Alexa" to comparable to Maple.
>
> Perhaps soon
>
> http://trac.sagemath.org/sage_trac/ticket/1000
>
> can be closed and replaced by a ticket to have 100,000 users?
>
>
> (and yes, I posted a version of the above email to
> http://sagemath.blogspot.com/)
>
>
> --
> William Stein
> Associate Professor of Mathematics
> University of Washington
> http://wstein.org
>
>
> --
> William Stein
> Associate Professor of Mathematics
> University of Washington
> http://wstein.org
>
> >
>

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[sage-devel] #1426: new trac view: tickets ***reported by*** given user

[David Harvey]

Hi paul,

is this what you wanted?

http://sagetrac.org/sage_trac/report/9

david


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[sage-devel] Re: #1426: new trac view: tickets ***reported by*** given user

[David Harvey]

On Dec 20, 2007, at 8:47 PM, Robert Miller wrote:

> David,
>
> Did you mean to attach something to that ticket?

no... sorry I put "[with patch]" but I really meant "[solution  
has been implemented]" but no-one ever writes that and I didn't want  
to feel left out :-(

The point is that there is a new "report" which allows you to easily  
see all the tickets you have reported, which is what paul apparently  
was asking for.

david


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[sage-devel] Re: #1426: new trac view: tickets ***reported by*** given user

[David Harvey]

On Dec 20, 2007, at 8:52 PM, Yi Qiang wrote:

> I believe it is supposed to be a custom view that shows tickets you've
> reported, although it's not working for me.

Are you logged in?

(I don't suppose you're seeing tickets reported by ME? (i.e. by  
dmharvey?) Did I mess up?)

david


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[sage-devel] Re: example of a Mathematica program from my lecture

[David Harvey]

On Dec 21, 2007, at 7:18 AM, mabshoff wrote:

>> But please don't forget, sage is about open source - and windows is
>> the complete opposite.
>
> [begin rant] Well, we support OSX, too, and that isn't exactly Open
> Source either. While Apple itself is somewhat more friendly to the
> Open Source idea than Microsoft on the software side you shouldn't

[...]

> I have been porting Software to and from Windows, OSX, Linux, Solaris,
> HPUX and so on for many years now and in my experience those ports
> always increase the quality of the code.[end rant]

Wow, michael, that was the most awesome rant I've ever seen on sage- 
devel.

I agree with you 150%. (well I reserve judgement on the women's  
track and field stuff, but let's not get into that.)

My opinion is that having a native windows port is easily the single  
most effective way to boost Sage's user base.

There are two problems. First is that a windows port is, as you point  
out, very, very (very, very) hard. Second problem, more important  
from an immediate practical point of view, is that the core of the  
sage developers don't know Windows, and don't have a convenient way  
to work with windows. You've seen at all the Sage Days workshops,  
it's like a macfest, with a couple of people running some kind of  
linux, and hardly anyone running windows. Moreover, most of us don't  
*want* to run windows.

I've said it before and I'll say it again: if someone can make  
working on windows as easy and legal for me as "ssh sage.math", then  
I would probably be able to find some time to help out. If this can  
be made to happen then I think you will find more people interested  
in working on the port.

david


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[sage-devel] latex functions in SAGE?

[David Joyner]

Hi:
I wonder what SAGE developers think of the following idea:
to include in SAGE some functions which make the
creation of latex structures easier (for the purpose of
writing papers, etc). I'm thinking of two things:
(a) outputting a tabular environment (with options for
left, center, right justifications),
(b) outputting a commutative diagram,
(c) outputting a simple picture environment (possibly even a 3d one),
I'm not sure how to do these, I was just wondering if this
seems interesting to others. I think in my case, it would make
some latex typesetting easier.
- David Joyner

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[sage-devel] Re: example of a Mathematica program from my lecture

[David Harvey]

On Dec 21, 2007, at 9:27 AM, Joel B. Mohler wrote:

>
> On Friday 21 December 2007 08:42, David Harvey wrote:
>> I've said it before and I'll say it again: if someone can make
>> working on windows as easy and legal for me as "ssh sage.math", then
>> I would probably be able to find some time to help out. If this can
>> be made to happen then I think you will find more people interested
>> in working on the port.
>
> The irony is that both "easy" and "legal" are not so trivially  
> attainable with
> *remote* use of windows.  For instance, the cygwin ssh service on  
> windows

[...]

So you mean, the only way to do it is that someone buys some big  
license from Microsoft which allows multi-user remote access? Pricing  
is (number of users) * (price per license)?

david


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[sage-devel] Re: example of a Mathematica program from my lecture

[David Harvey]

On Dec 21, 2007, at 10:16 AM, Joel B. Mohler wrote:

>> So you mean, the only way to do it is that someone buys some big
>> license from Microsoft which allows multi-user remote access? Pricing
>> is (number of users) * (price per license)?
>
> That is my impression -- I don't know if the price per user can be  
> less than
> price per license for local install.  All of my past MS licensing  
> experience
> has implied per user fees.  Although some windows OS licenses are
> per-computer, but there have always been (in my experience) clauses  
> closing
> the loop-holes for lots of thin clients.

Well damn. I guess this is the cost of doing development for Windows.

So these are my options:

(1) Use the windows lab on campus. Problem is, I believe for security  
reasons they wipe off the machines every day. I suppose I have some  
kind of permanent "home directory", but I'm not sure if I can install  
things like compilers into it. Also it's a colossal pain to lug  
myself over there, I don't know if I'd ever actually do it.

(2) Use my wife's laptop. Not a good option: I don't want to mess  
with the OS at all, there's hardly any hard drive space left, the  
machine crashes regularly, and she needs it all the time.

(3) Buy a windows license and use one of the virtualisation options  
mentioned before on this list to run it on my macbook. Not a good  
option: I'm too cheap.

(4) I wonder if it's possible for the Sage foundation to set up a  
server and buy a small number of windows licenses for remote access.  
Say like 4 licenses, so only four people can be logged in at a time.  
Maybe that's a cost effective and legal way to do this. (Oh yeah, and  
then tell me I have to pay money for the client software too. Please  
say no.)

david


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[sage-devel] #1482: xgcd suboptimal output

[David Harvey]

Hi Nils,

I've been looking at

http://www.sagetrac.org/sage_trac/ticket/1482

and approximately diagnosed the problem (see comments on the ticket),  
but it's not clear to me exactly how to proceed.

The new underlying gcd code produces quite inscrutable output, for  
example:

sage: xgcd(3, 3)
(3, 0, 1)
sage: xgcd(3, 6)
(3, -3, 2)
sage: xgcd(3, 9)
(3, -8, 3)
sage: xgcd(3, 12)
(3, -3, 1)
sage: xgcd(3, 15)
(3, -14, 3)
sage: xgcd(3, 18)
(3, -17, 3)
sage: xgcd(3, 21)
(3, -20, 3)
sage: xgcd(3, 24)
(3, -15, 2)
sage: xgcd(3, 27)
(3, -26, 3)
sage: xgcd(3, 30)
(3, -29, 3)
sage: xgcd(3, 33)
(3, -32, 3)
sage: xgcd(3, 36)
(3, -35, 3)
sage: xgcd(3, 39)
(3, -38, 3)
sage: xgcd(3, 42)
(3, -41, 3)
sage: xgcd(3, 45)
(3, -44, 3)
sage: xgcd(3, 48)
(3, -15, 1)
sage: xgcd(3, 51)
(3, -50, 3)

It's very hard to see any rhyme or reason in that. Certainly the GMP  
documentation doesn't guarantee any properties of the cofactors,  
apart from bezout, either at the mpz or mpn levels, so it's not a bug.

I'm inclined to do the following in Sage. Provide a "fast" flag which  
just calls GMP and doesn't provide any guarantees about the output  
(apart from satisfying bezout). If "fast" is False (default), then we  
convert to a "standard" form, which should be unique, mathematically  
sensible, and carefully documented.

But having thought about it for a while, it's not even clear to me  
what exactly the right definition of "standard" should be. I don't  
quite understand the minimality condition you proposed.

Apart from the kind of special case listed above, GMP does seem to  
follow some "rules", but I'm not sure they are always satisfied, and  
we can't rely on them since the GMP documentation doesn't promise  
anything.

For example, if 0 < a < b, then xgcd(a, b)[1] always seems to be  
negative and xgcd(a, b)[2] always positive, but it swaps around if 0  
< b < a:

sage: xgcd(11, 17)
(1, -3, 2)
sage: xgcd(17, 11)
(1, 2, -3)

i.e. it looks like it swaps them to make a < b, and then swaps the  
cofactors at the end.

It generally seems to handle input signs in the same way, i.e. it  
first does xgcd(|a|, |b|), then throws the signs back in at the end:

sage: xgcd(11, 17)
(1, -3, 2)
sage: xgcd(-11, 17)
(1, 3, 2)
sage: xgcd(11, -17)
(1, -3, -2)
sage: xgcd(-11, -17)
(1, 3, -2)

But none of this is particularly canonical.

What's the "right" way to do this?

david


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[sage-devel] Re: Beautiful Screen Shot Collection - GHOP

[David Joyner]

1. This is great but Hamming codes are definitely not cryptographic!
They are error-correcting codes (redundant information allowing
for example your CD player to play music, even though your CD has
scratches/errors),
not ciphers (the encryption used so that, for example,you cannot easily
hijack someone's electronic credit card transaction).

2. Here's another plot you might find amusing:
sage: rubik = CubeGroup()
sage: P = 
rubik.plot3d_cube("U^2*F*U^2*L*R^(-1)*F^2*U*F^3*B^3*R*L*U^2*R*D^3*U*L^3*R*D*R^3*L^3*D^2")
sage: show(P)
It's the "superflip+4 spot" (in 26q moves, known to be a minimal manuever).
Some conjecture this to be the "longest" move in the quarter-turn metric.


On Dec 23, 2007 6:49 PM, Timothy Clemans <[EMAIL PROTECTED]> wrote:
>
> David who is a high school student in Long Island, New York created 41
> screen shots and titles and captions for them for his first task in
> the Google Highly Open Participation Contest. He released his work
> under the Creative Commons Share-a-like license. I uploaded his work
> to Flickr and you can see it at 
> http://www.flickr.com/photos/sagescreenshots/sets/72157603532209437/.
> I think the slide show (http://www.flickr.com/photos/sagescreenshots/
> sets/72157603532209437/show/) with info on (click on the 'I') is
> particularly dramatic.
> >
>

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[sage-devel] Re: SAGE-2.9.1

[David Harvey]

When I upgrade from 2.9 to 2.9.1, the FLINT test suite is being run.  
Probably it's a good idea to disable this in the release versions,  
it's quite time-consuming?

Also I noticed this during the test suite (mac os 10.4.10, ppc g5):

[...]

Testing fmpz_convert()... ok
Testing fmpz_size()... ok
Testing fmpz_bits()... ok
Testing fmpz_sgn()... ok
Testing fmpz_set_si()... ./spkg-check: line 50: 25204 Abort  
trap  ./fmpz-test
Testing fmpz_poly_tofromstring()... ok

[...]

??

david

On Dec 24, 2007, at 1:50 PM, William Stein wrote:

>
> Hi,
>
> SAGE-2.9.1 has been released.
>
> See
>  http://sagemath.org/announce/sage-2.9.1.txt
> for the release notes (which I've copied below).
>
> Download the source code from:
>  http://sagemath.org/dist/src/i
>
> Binaries will be available in a day or two.
>
>  William


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[sage-devel] Re: writing an interpeter for mathematica language

[David Joyner]

Also, the "Legal questions" section of http://omath.org/wiki/Main_Page
might be worth reading before you get started.


On Dec 24, 2007 7:20 PM, root <[EMAIL PROTECTED]> wrote:
>
> Ondrej
>
> >I am thinking for a long time already of writing an interpreter, in
> >Python of course, of the Mathematica
> >language:
>
> Such a language interpreter exists already, called MockMMA, I believe.
> Check with Richard Fateman.
>
> Tim
>
>
>
> >
>

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[sage-devel] Re: SAGE-2.9.1

[David Harvey]

On Dec 24, 2007, at 7:40 PM, Bill Hart wrote:

>
> I did find some occurrences of 63 instead of FLINT_BITS-1, but I don't
> believe this should be causing any problems with that function.
>
> Since the function doesn't say fail, I can only imagine this is an out
> of memory problem. But I don't see any leaks, nor any requests for
> large blocks.
>
> Can you tell me what happens when you run fmpz-test on its own on the
> G5. A global search and replace of 63 with FLINT_BITS-1 will fix the
> abovementioned.

I changed the 63 to 31 in test_fmpz_set_si, and now it seems to work  
(and subsequently fails on the test_fmpz_set_ui test, presumably for  
the same reason).

Kind of surprising that the test was passing on all those 32-bit  
machines out there.

Note that the G5 is a 64-bit machine, but in sage everything only  
compiles in 32-bit mode.

david


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[sage-devel] sagemath.org metadata

[David Harvey]

When you google for "mathematica", at the top of the search results  
you get this a bunch of extra links ("Students", "Mathematica Home  
Page", "Demonstrations Project", etc.)

I'm not sure how this works, I guess it's some meta-data in the html  
of the mathematica website. I'm sure someone on this list knows how  
this works.

Now that Sage is #1 on google, it would be good to have some of our  
links like this. At the very least, we should have a "notebook" link,  
a "download" link, and a "tutorial" link.

david


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[sage-devel] Re: typo in sage tutorial

[David Joyner]

I added this to
http://sagetrac.org/sage_trac/ticket/1544
and attached a patch.

On Dec 26, 2007 8:18 PM, William Stein <[EMAIL PROTECTED]> wrote:
> Dear Matthew,
>
> Thanks for your bug report!
>
> Dear David Joyner (cc: sage-devel):
>
> This is in some latex that you wrote.  Any ideas?


Simply replaced \vdots by ...


>
> I've made this trac #1602:
> http://trac.sagemath.org/sage_trac/ticket/1602
>
>
> -- Forwarded message --
> From: Matthew Moelter <>
> Date: Dec 26, 2007 4:24 PM
> Subject: typo in sage tutorial
> To: [EMAIL PROTECTED]
>
>
> on this page
>
> http://www.sagemath.org/doc/html/tut/node24.html
>
> in the table there is what appears to be raw latex rather than
> typeset material.
> this appears "&vellip#vdots;"
>
> Matt
>
>
>
> Matthew Moelter, Assoc Prof
> Department of Physics
> Calif. Polytechnic State Univ.
> San Luis Obispo, CA 93407
>
>
>
>
>
>
> --
> William Stein
> Associate Professor of Mathematics
> University of Washington
> http://wstein.org
>

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[sage-devel] Re: SAGE Tutorial nits #2

[David Joyner]

I added a link to a patch on the comment section of
http://sagetrac.org/sage_trac/ticket/1544
It passes sage -t.

+

On Dec 16, 2007 10:22 PM, mabshoff
<[EMAIL PROTECTED]> wrote:
>
>
>
> On Dec 17, 2:28 am, Rich Morin <[EMAIL PROTECTED]> wrote:
> > As requested by WS, I'm posting these directly to the list.
> >
> > -r
>
> Thanks Rich,
>
> your fixes are now #1544. Keep up the great work :)
>
> Cheers,
>
> Michael
>
> >
>

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[sage-devel] Re: Fwd: About SAGE

[David Joyner]

On Dec 27, 2007 3:40 AM, William Stein <[EMAIL PROTECTED]> wrote:
>
> Hi,
>
> I occasionally get emails like the one below.  There's no way I have the
> time or inclination to burn and mail out DVD's of Sage to people.  Does
> anybody:
>
>(1) want to volunteer to do this sort of thing in exchange for some
>  "shipping and handling fees"; then all such requests get
>  refereed to you, or
>
>(2) Is there some dot-com that does something like this for a fee?




Maybe lulu does:
http://www.lulu.com/en/help/disc_faq
Apparently, It has to be set up first and I don't know how easy it is to
upgrade to a new version.


>  It seems like the sort of thing that would make for a dot-com
>  business model.
>
>  -- William
>
> -- Forwarded message --
> From:...
> Date: Dec 23, 2007 10:05 AM
> Subject: Re: About SAGE
> To: William Stein <[EMAIL PROTECTED]>
>
>
> Dear Prof. Stein,
>
> I am looking forward to meeting you after Jan. 10th. I
> would really appreciate if you could send me a DVD of
> SAGE to my home address. I will be happy to pay for
> the postage. Please let me know. Here is my home
> address:
>
> Thanks in advance.
>
> Pacha
> 
>
> --- William Stein <[EMAIL PROTECTED]> wrote:
>
> > On Dec 22, 2007 11:59 AM, Pacha Nambi
> > <[EMAIL PROTECTED]> wrote:
> > > Dear Prof. Stein,
> > >
> > > I read last night an article at the MAA website
> > about
> > > SAGE. I want to state that what you and your
> > students
> > > are doing is fantastic. I downloaded the program
> > last
> > > night, and going to test it out.
> > >
> > > I have used 'Mathematica' for about a year now.
> > > However, its is too expensive for student use.
> > >
> > > I live near UW and would like to the campus and
> > chat
> > > with you. Is that possible?
> >
> > I won't be back in Seattle until Jan 10.  Could you
> > contact
> > me again around then?  We could definitely meet.
> >
> >  -- William
> >
> > >
> > > I teach (chemistry and computer classes) at local
> > > community colleges in the Seattle area.
> > >
> > > Regards,
> > > Pacha Nambi
> > >
> > > (206) 363-9416 (home phone)
> > >
> > >
> > >
> >
> >
> >
> > --
> > William Stein
> > Associate Professor of Mathematics
> > University of Washington
> > http://wstein.org
> >
>
>
>
>
>
> --
> William Stein
> Associate Professor of Mathematics
> University of Washington
> http://wstein.org
>
> >
>

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[sage-devel] Re: SAGE Tutorial nits #2

[David Joyner]

On Dec 27, 2007 12:20 AM, mabshoff
<[EMAIL PROTECTED]> wrote:
>
>
>
> On Dec 27, 5:55 am, "David Joyner" <[EMAIL PROTECTED]> wrote:
> > I added a link to a patch on the comment section 
> > ofhttp://sagetrac.org/sage_trac/ticket/1544
> > It passes sage -t.
> >
>
> Hi David,
>
> I assume the bundle linked from #1544 also fixes #1602? If it is a
> single commit only could you attach a patch instead of a bundle?


Yes, 1602 too. It isn't a single comment. What is the difference
between a patch and a bundle?
William pointed out in another email, I have forgotten somethings, so
it is probably best to ignore
this patch/bundle, if it isn't too late.


>
> Cheers,
>
> Michael
>
> > +
> >
> > On Dec 16, 2007 10:22 PM, mabshoff
> >
>
> > <[EMAIL PROTECTED]> wrote:
> >
> > > On Dec 17, 2:28 am, Rich Morin <[EMAIL PROTECTED]> wrote:
> > > > As requested by WS, I'm posting these directly to the list.
> >
> > > > -r
> >
> > > Thanks Rich,
> >
> > > your fixes are now #1544. Keep up the great work :)
> >
> > > Cheers,
> >
> > > Michael
> >
>

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[sage-devel] Re: sage-2.9.2

[David Joyner]

On Dec 27, 2007 3:37 AM, William Stein <[EMAIL PROTECTED]> wrote:
>
> Hi,
>
> Who is the release manager for Sage-2.9.2?  I'm hoping for a good
> release, which
> happens by Jan 4, 2008, in time for making some DVD's for the AMS meeting and
> having some user testing.   It should thus be a bug-fix conservative,
> etc., release.
> I'm guessing Michael Abshoff should be release manager for 2.9.2 :-)
>
> We also should start thinking hard about what needs to happen for
> version 2.10 and beyond.
> In particular, we should also start planning what's needed for 3.0. I
> think the main goals for
> 3.0 should be:
>
> (1) Solaris 10 support on Opteron and Sparc,
>
> (2) Good usable interactive 3d graphics that really work in the
> context of the rest of Sage.
>   Sage pretty much covers every major area of mathematics now,
> but is week at 3d
>   graphics.
>
> There are also numerous misc polish, bug fixes, improvements, etc.,
> all over the place, which
> the trac tickets nicely record.  But I think 1 and 2 above are the
> biggies that we've been
> failing to achieve for years now, that we really really need to do.
> What do you think?


Agreed, good 3d graphics will be a major milestone. Amazingly, it seems
like it might be available soon! Very exciting.



>
>  -- William
>
> --
> William Stein
> Associate Professor of Mathematics
> University of Washington
> http://wstein.org
>
> >
>

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[sage-devel] Re: SAGE Tutorial nits #2

[David Joyner]

A new patch has been posted to
http://sage.math.washington.edu/home/wdj/patches/tut20071227.hg
Passes sage -t. Also, the new version of tut.tex is at
http://sage.math.washington.edu/home/wdj/patches/tut.tex
This includes the fixes of every typo i know of and some added examples.


On Dec 27, 2007 8:12 AM, David Joyner <[EMAIL PROTECTED]> wrote:
> On Dec 27, 2007 12:20 AM, mabshoff
> <[EMAIL PROTECTED]> wrote:
> >
> >
> >
> > On Dec 27, 5:55 am, "David Joyner" <[EMAIL PROTECTED]> wrote:
> > > I added a link to a patch on the comment section 
> > > ofhttp://sagetrac.org/sage_trac/ticket/1544
> > > It passes sage -t.
> > >
> >
> > Hi David,
> >
> > I assume the bundle linked from #1544 also fixes #1602? If it is a
> > single commit only could you attach a patch instead of a bundle?
>
>
> Yes, 1602 too. It isn't a single comment. What is the difference
> between a patch and a bundle?
> William pointed out in another email, I have forgotten somethings, so
> it is probably best to ignore
> this patch/bundle, if it isn't too late.
>
>
>
> >
> > Cheers,
> >
> > Michael
> >
> > > +
> > >
> > > On Dec 16, 2007 10:22 PM, mabshoff
> > >
> >
> > > <[EMAIL PROTECTED]> wrote:
> > >
> > > > On Dec 17, 2:28 am, Rich Morin <[EMAIL PROTECTED]> wrote:
> > > > > As requested by WS, I'm posting these directly to the list.
> > >
> > > > > -r
> > >
> > > > Thanks Rich,
> > >
> > > > your fixes are now #1544. Keep up the great work :)
> > >
> > > > Cheers,
> > >
> > > > Michael
> > > >
> >
>

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[sage-devel] Re: [Axiom-developer] Rosetta translations

[David Joyner]

I think this is a great idea.

What distribution license does the rosetta tex file have?


On 12/28/07, TimDaly <[EMAIL PROTECTED]> wrote:
> At  is a document that is
> designed
> to help users of new systems "translate" simple ideas from their
> current systems.
> (The source is at ). I do
> not know
> Sage well enough to update this information. Is there anyone here who
> can
> propose Sage equivalent commands so they can be added to the document?
> It should only take a few minutes for an experienced Sage user.
>
> Please send me email or post an updated version of the document
> somewhere.
>
> Such a translation would be a trivial introduction to Sage and could
> be added
> to the distribution.
>
> Tim Daly
>
>
>
> ___
> Axiom-developer mailing list
> [EMAIL PROTECTED]
> http://lists.nongnu.org/mailman/listinfo/axiom-developer
>

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[sage-devel] Re: Most Sage spkg's are out of date!

[David Joyner]

On Dec 28, 2007 2:38 PM, William Stein <[EMAIL PROTECTED]> wrote:
>
> On Dec 28, 2007 3:54 AM, Ondrej Certik <[EMAIL PROTECTED]> wrote:
> >
> > Are there some instructions for Sage package maintainers to follow?
> > I.e. what exact steps are neede to update the package?
>
> There are no instructions, and no master list of package maintainers, etc.
> One of the goals of this thread is to create such things.
>
> > 1) create a new spkg
> > 2) create a trac ticket and attach it? or expose the repository, so
> > that you can build it yourself?
> > 3) write to the mailinglist?
>
> We need:
>   (a)  a wiki page that lists packages with the corresponding maintainer.

I've created

http://wiki.sagemath.org/standard_packages_available_for_SAGE

http://wiki.sagemath.org/optional_packages_available_for_SAGE

http://wiki.sagemath.org/experimental_packages_available_for_SAGE

The information on these pages varies but I think all items need  work.


>   (b) A natural system for updating patches.  I like your suggestion above,
> though _not_ the order.
>   (1) Create a trac ticket describing that the package is out of date.
> This should _already_ be done for every package I listed at
>  the beginning of this email.
>   (2) Accept the trac ticket when you're about to make a new spkg.
>   (3) Post a link from the trac ticket to the new spkg (don't
> attach it, since
> it is too big.)
>   (4) Post to sage-devel announcing the new spkg and requesting
> feedback and testing.  Any such email *must* list some tests
> a user can try after "sage -i" 'ing the package to test that
> it actually installed OK.  All feedback from such testing
> should be pasted into the trac ticket.  The trac ticket should
> be assigned against an upcoming release of Sage.
>  (5)  The release manager puts the new spkg in Sage once it
> has got a positive review as a part of (4).
>
> Thoughts?
>
>  -- William
>
>
> >
>

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[sage-devel] Re: factor ideals at NF

[David Roe]

The issue is that since Sage uses pari to do everything in the background,
one needs to create the pari data structures, which means that you currently
call nfinit on the number field, which computes the class group and unit
group.  This should change eventually, but right now...
David

On Dec 29, 2007 2:10 PM, Enrique Gonzalez-Jimenez <
[EMAIL PROTECTED]> wrote:

>
> As John Cremona said at the sage.forum: "But why would Sage be
> computing the class group in order to factor 2 in K?"
>
>
> For me that is strange too. Since it would be easier to compute the
> factorization of an ideal generate by a prime.
>
> For example: Using the Proposition that asserts that if K is a number
> field and the ring of integers is of the form O_K=Z[alpha] (where f(t)
> is the minimal polynomial over Z of alpha) then to compute the
> factorization of the ideal O_K where p is a rational prime is
> enough to factorize f(t)mod p. That is, if
> f(t)=f_1(t)^r_1...f_s(t)^r_s (mod p) then the factorization on prime
> ideal is of the form
>
> O_K=^r_1...^r_s.
>
> Enrique
>
> On 29 dic, 21:42, Bill Hart <[EMAIL PROTECTED]> wrote:
> > It presumably can't compute the class group, because of the proof=true
> > thing. Basically if you want a proven result, it is going to take
> > forever and will need more primes than Pari has precomputed.
> >
> > It's not clear to me if SAGE is actually catching the error message,
> > or if it is just raising an exception because Pari did something it
> > wasn't expecting (i.e. print an error message).
> >
> > Bill.
> >
> > On 29 Dec, 20:27, mabshoff <[EMAIL PROTECTED]
> >
> > dortmund.de> wrote:
> > > On Dec 29, 9:17 pm, [EMAIL PROTECTED] wrote:
> >
> > > > Hello:
> >
> > > > I am working at my Number Theory lectures and I have found a bug
> (?). This is
> > > > the output:
> >
> > > > ///   SAGE 2.9.1   ///
> > > > sage: K.=CyclotomicField(23)
> > > > sage: O=K.maximal_order()
> > > > sage: (2*O).factor()
> > > >   ***   Warning: large Minkowski bound: certification will be VERY
> long.
> > > > Traceback (most recent call last):
> > > >   File "", line 1, in 
> > > >   File "/home/notebook/sage_notebook/worksheets/admin/3/code/13.py",
> > > > line 4, in 
> > > > exec compile(ur'(Integer(2)*O).factor()' + '\n', '', 'single')
> > > >   File
> > > > "/usr/local/sage/local/lib/python2.5/site-packages/sympy/plotting/",
> > > > line 1, in 
> >
> > > >   File "sage_object.pyx", line 92, in
> > > > sage.structure.sage_object.SageObject.__repr__
> > > >   File
> > > >
> "/usr/local/sage/local/lib/python2.5/site-packages/sage/structure/factor\
> > > > ization.py", line 187, in _repr_
> > > > t = str(self[i][0])
> > > >   File
> > > >
> "/usr/local/sage/local/lib/python2.5/site-packages/sage/rings/number_fie\
> > > > ld/number_field_ideal.py", line 218, in __repr__
> > > > return "Fractional ideal %s"%self._repr_short()
> > > >   File
> > > >
> "/usr/local/sage/local/lib/python2.5/site-packages/sage/rings/number_fie\
> > > > ld/number_field_ideal.py", line 235, in _repr_short
> > > > return '(%s)'%(', '.join([str(x) for x in self.gens_reduced()]))
> > > >   File
> > > >
> "/usr/local/sage/local/lib/python2.5/site-packages/sage/rings/number_fie\
> > > > ld/number_field_ideal.py", line 553, in gens_reduced
> > > > dummy = self.is_principal(proof)
> > > >   File
> > > >
> "/usr/local/sage/local/lib/python2.5/site-packages/sage/rings/number_fie\
> > > > ld/number_field_ideal.py", line 714, in is_principal
> > > > bnf = self.number_field().pari_bnf(proof)
> > > >   File
> > > >
> "/usr/local/sage/local/lib/python2.5/site-packages/sage/rings/number_fie\
> > > > ld/number_field.py", line 1464, in pari_bnf
> > > > self.pari_bnf_certify()
> > > >   File
> > > >
> "/usr/local/sage/local/lib/python2.5/site-packages/sage/rings/number_fie\
> > > > ld/number_field.py", line 1497, in pari_bnf_certify
> > > > if self.pari_bnf(certify=False, units=True).bnfcertify() != 1:
> > > >   File &quo

[sage-devel] Re: Most Sage spkg's are out of date!

[David Joyner]

On Dec 30, 2007 6:14 PM, Ondrej Certik <[EMAIL PROTECTED]> wrote:
>
> On Dec 30, 2007 11:58 PM, Francois <[EMAIL PROTECTED]> wrote:
> >
> >
> >
> > On Dec 31, 1:51 am, "Ondrej Certik" <[EMAIL PROTECTED]> wrote:
> > >
> > > Disclaimer: I am a Debian user, on the way of becoming a Debian Developer
> > >
> > > I agree with Michael, to keep it simple stupid, as it is now. Maybe with 
> > > my
> > > a simple improvements I suggested here:
> > >
> > > http://groups.google.com/group/sage-devel/browse_thread/thread/6b9684...
> > >
> > > Nice thing about this is that there is no database, nothing. Just
> > > plain files, that
> > > can be fixed by hand.
> > >
> > > How would portage improve this?
> >
> > Note I initially posted this privately to Ondrej with a disclaimer
> > about not starting
> > rant wars but he encouraged me to post it list-wide.
>
> Yes, some Sage developers like Michael love flamebates. :)
>
>
> > Disclaimer: I am a Gentoo user which should really become the
> > maintainer
> > of several packages :) [real life commitment permitting]
> >
> > I am just feeling that spkg is re-inventing/has re-invented the wheel.
> > On the other hand full blown portage is certainly too bloated - did I
> > mention
> > anything about subsets of portage?
> > I think there should be a kind of portage-redux for stuff that are not
> > full fledged
> > Linux meta-distribution. Modular xorg comes to mind as something that
> > has pretty
> > much become a distribution and could use such system. Portage-redux
> > definitely
> > doesn't belong to this list.
> >
> > Since my understanding is that you can actually use dpkg to compile
> > debian from
> > source it could probably be applied there as well.
> >
> > The only improvement that I can see would be an ease of integration in
> > Gentoo
> > which is a bit too Gentoo-centric to be of any real benefit to anyone
> > else. More
> > discipline in the packaging is probably what is most needed at the
> > moment. And
> > you can package stuff as badly in ebuilds than you can in spkgs so
> > that wouldn't
> > really enforce discipline. So pragmatically none.
>
> I thought the same at the beginning that Sage is just reinventing the wheel
> (especially when Sage people don't like reinventing the wheel:), but
> I don't think there is any other way. The requirements are:
>
> * keep it simple (plain config files, the less, the better)
> * need to work everywhere where Sage works
>
> But you are right, that imho, Sage is becoming a distribution, for
> mathematics software.
> And a very convenient one. Imagine just writing your program, then
> creating a spkg
> and then being able to install it from source on linux, windows,
> mac... You cannot
> do that with a Gentoo or Debian package alone.

Well said!

>
> Ondrej
>
>
> >
>

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[sage-devel] Re: first aliquot factor found by SAGE ECM interface

[David Joyner]

IMHO, this is very interesting. Perhaps this be posted to someone's
SAGE blog, so it shows up on planet sage? Of course, I can post it to mine
but maybe someone else wants to provide more detailed comments?


On Jan 2, 2008 3:18 AM, Paul Zimmermann <[EMAIL PROTECTED]> wrote:
>
> William asked me to forward this to sage-devel:
>
> > the SAGE ECM interface found a first factor of the aliquot sequence starting
> > by 552:
> >
> >remains 
> > 23648161798622140141259448258749760352819524456141488104537419990481892694930432002158957619604181055633215274583954462907657503167424176909
> >  (140 digits)
> >found factor by ecm: 58417195751812372006463994075468288063413 with 
> > parameters {'poly': 'Dickson(6)', 'sigma': '300411371', 'B1': '3990569', 
> > 'B2': '8561602150'}
> >
> > Other nice factors will surely follow.
> > Paul
>
> An aliquot sequence is simply the iteration of the function n -> sigma(n)-n,
> where sigma(n) is the "sum of divisors" function. One open question from
> Catalan is whether this sequence always converges to 1 (or to a cycle). The
> first to perform extensive computations on aliquot sequences was Lehmer, who
> found that all sequences starting from n <= 1000 converge, except perhaps
> n=276, 552, 564, 660 and 966. These are the "Lehmer five" sequences. Since
> several years, together with other people, I try to extend these Lehmer five
> sequences. The main difficulty is that to compute sigma(n), you have to
> factor n. For the current large numbers we encounter (150-160 digits) we use
> a combination of different algorithms (ECM, QS, NFS). I have now converted
> to SAGE the script that (tries to) extend aliquot sequences. The above
> factorization is a first success of the new script.
>
> Paul Zimmermann
>
> PS: for more details, see http://www.loria.fr/~zimmerma/records/aliquot.html
>
> >
>

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[sage-devel] Re: AMS conference

[David Joyner]

I'll be there.

On Jan 6, 2008 3:53 AM, William Stein <[EMAIL PROTECTED]> wrote:
>
> Hi,
>
> The AMS exhibit booth Grand Opening is at noon on Sunday.
>
> I plan to meet people who are interested in helping me setup *and* who
> are staying
> at the 500 West at 9:30am in the lobby.  We'll leave for the AMS meeting from
> there.   I have a _lot_ of papers / box, etc., to carry over... (but I
> also have a small
> car tomorrow, which might be helpful).  If you're not staying at the
> 500 West you
> might be able to somehow get into the exhibit hall and help with setup
> -- I don't know.
>
>  -- William
>
> --
> William Stein
> Associate Professor of Mathematics
> University of Washington
> http://wstein.org
>
> >
>

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