Re: multidimensional "arrays"
Hi, DATA = [ [ 0 for i in range(ncolumns) ] for i in range(nrows) ] Is one way. DON'T do it like this: row = [0] * ncolumns data = [ row ] * nrows # WRONG! Since after that, every row is the exact same object; if you set data[0][0] = 1, the first element of _every_ row is 1. But I guess you already found out about that :-) That said, are you sure a list of lists is the best data structure for what you're trying to do? I keep being surprised by Python code that uses other data structures in clever ways; lists of lists seem to be pretty rare! Remco Gerlich On Dec 6, 2007 4:29 PM, Horacius ReX <[EMAIL PROTECTED]> wrote: > in python, when I want to use arrays, I follow this way; > > DATA = [0] * nint > > and when I want to use I do; > > > > DATA[i] = > > do you know how to do similar but in two dimensions ? > > thanks > -- > http://mail.python.org/mailman/listinfo/python-list > -- http://mail.python.org/mailman/listinfo/python-list
Re: what the heck does this mean?
On Dec 13, 2007 4:57 AM, katie smith <[EMAIL PROTECTED]> wrote: > Traceback (most recent call last): > File "C:\Python25\empire\Empire Strategy.pyw", line 322 > Maty = Searched(number) > TypeError: 'list' object is not callable > This is the error message. The first line basically says "This is what happened:" The second shows the file, and the line number. The third is the actual line. Then the error message: you had a list object, and you tried to call it. Well, looking at that line, we see Searched(number). Search is apparently a list, and you used ( ) on it, which tries to call it, but that's not possible. So that's the mistake - you meant to use [ ], but used ( ). > so Maty Searched(number is supposed to give me 0 when > Search = "NewMap" > number = 0 > bignum = 1 > bignumer = repr(bignum) > Searching = Search+bignumer > Searched = eval(Searching) > Maty = Searched[number] > This isn't the actual code that gave the error message - here you used [ ]. > Anyway, doing it like this is really bad and likely to go wrong, but that's not your question. Remco Gerlich -- http://mail.python.org/mailman/listinfo/python-list
Re: Question from a python newbie
On Dec 13, 2007 4:39 PM, Russell <[EMAIL PROTECTED]> wrote: > I've been learning Python slowly for a few months, coming from a C/C+ > +, C#, Java, PHP background. I ran across a code fragment I'm having > trouble wrapping my brain around. I've searched the Language > Reference and was not able to find any info regarding the structure of > this code fragment: > > int(text) if text.isdigit() else text Hi, It's a pretty new construct; basically it's Python's version of the ? : "ternary operator" in other languages. The line above is equivalent to text.isdigit() ? int(text) : text in, for instance, C. Remco Gerlich -- http://mail.python.org/mailman/listinfo/python-list
Re: How to get memory size/usage of python object
Hi, The only list without references to other objects in it is [ ]. 0, 1, 2, etc are objects. Every value in Python is a reference to an object. Remco On Jan 10, 2008 9:14 AM, Santiago Romero < [EMAIL PROTECTED]> wrote: > > > Would you care to precisely define "REAL size" first? Consider: > > > > >>> atuple = (1, 2) > > >>> mylist = [(0, 0), atuple] > > > > Should sizeof(mylist) include sizeof(atuple) ? > > No, I'm talking about "simple" lists, without REFERENCES to another > objects into it. > > I mean: > > lists = [ 0, 1, 2, 3, 4, (1,2), 3] > > or > > array = [ [0,0,0,0,0,0,0], [1,1,1,1,2,1,2], ... ] > > Maybe I can "pickle" the object to disk and see the filesize ... :-? > > -- > http://mail.python.org/mailman/listinfo/python-list > -- http://mail.python.org/mailman/listinfo/python-list
Re: Loop in a loop?
Use zip() to combine them into a single list, then loop over that: for x, y in zip(array1, array2): ... Remco On Jan 17, 2008 1:21 PM, Sacred Heart <[EMAIL PROTECTED]> wrote: > Hi, > I'm new to Python and have come across a problem I don't know how to > solve, enter com.lang.python :) > > I'm writing some small apps to learn the language, and I like it a lot > so far. > > My problem I've stumbled upon is that I don't know how to do what I > want. I want to do a loop in a loop. I think. > > I've got two arrays with some random stuff in, like this. > > array1 = ['one','two','three','four'] > array2 = ['a','b','c','d'] > > I want to loop through array1 and add elements from array2 at the end, > so it looks like this: > > one a > two b > three c > four c > > I'm stuck. I know how to loop through the arrays separatly and print > them, but both at the same time? Hmmm. > > A push in the right direction, anyone? > > R, > SH > -- > http://mail.python.org/mailman/listinfo/python-list > -- http://mail.python.org/mailman/listinfo/python-list
Re: Excess whitespace in my soup
Not sure if this is sufficient for what you need, but how about
import re
re.sub(u'[\s\xa0]+', ' ', s)
That should replace all occurances of 1 or more whitespace or \xa0
characters, by a single space.
Remco
On Jan 19, 2008 12:38 PM, John Machin <[EMAIL PROTECTED]> wrote:
> I'm trying to recover the original data from some HTML written by a
> well-known application.
>
> Here are three original data items, in Python repr() format, with
> spaces changed to tildes for clarity:
>
> u'Saturday,~19~January~2008'
> u'Line1\nLine2\nLine3'
> u'foonly~frabjous\xa0farnarklingliness'
>
> Here is the HTML, with spaces changed to tildes, angle brackets
> changed to square brackets,
> omitting \r\n from the end of each line, and stripping a large number
> of attributes from the [td] tags.
>
> ~~[td]Saturday,~19
> ~~January~2008[/td]
> ~~[td]Line1[br]
> Line2[br]
> Line3[/td]
> ~~[td]foonly
> ~~frabjous farnarklingliness[/td]
>
> Here are the results of feeding it to ElementSoup:
>
> >>> import ElementSoup as ES
> >>> elem = ES.parse('ws_soup1.htm')
> >>> from pprint import pprint as pp
> >>> pp([(e.tag, e.text, e.tail) for e in elem.getiterator()])
> [snip]
> (u'td', u'Saturday, 19\n January 2008', u'\n'),
> (u'td', u'Line1', u'\n'),
> (u'br', None, u'\nLine2'),
> (u'br', None, u'\nLine3'),
> (u'td', u'foonly\n frabjous\xa0farnarklingliness', u'\n')]
>
> I'm happy enough with reassembling the second item. The problem is in
> reliably and
> correctly collapsing the whitespace in each of the above five
> elements. The standard Python
> idiom of u' '.join(text.split()) won't work because the text is
> Unicode and u'\xa0' is whitespace
> and would be converted to a space.
>
> Should whitespace collapsing be done earlier? Note that BeautifulSoup
> leaves it as -- ES does the conversion to \xa0 ...
>
> Does anyone know of an html_collapse_whitespace() for Python? Am I
> missing something obvious?
>
> Thanks in advance,
> John
> --
> http://mail.python.org/mailman/listinfo/python-list
>
--
http://mail.python.org/mailman/listinfo/python-list
Re: How avoid both a newline and a space between 2 print commands?
Hi,
Use
import sys
sys.stdout.write("foo")
sys.stdout.write("bar")
(and, possibly, sys.stdout.flush() to get the text to show up, it might wait
for the end of a complete line otherwise).
The alternative
import sys
print "foo",
sys.stdout.softspace=0
print "bar"
is just too hackish.
In Python 3, this will be improved!
Remco
On Jan 23, 2008 3:03 PM, [EMAIL PROTECTED] <[EMAIL PROTECTED]>
wrote:
> print "foo"
> print "bar"
>
> has a newline in between "foo" and "bar"
>
> print "foo",
> print "bar"
>
> has a space in between "foo" and "bar"
>
> How prevent ANYTHING from going in between "foo" and "bar" ??
>
> (Without defining a string variable.)
>
> Chris
> --
> http://mail.python.org/mailman/listinfo/python-list
>
--
http://mail.python.org/mailman/listinfo/python-list
Re: validate string is valid maths
Hi, It seems that for every group of 2 or more +-/* signs, one of the following holds: - The group starts with '-', everything after it should be dropped, otherwise - The second character is '-', everything after it should be dropped, otherwise - Drop everything after the first. That should turn into one short regex. Did I miss something? Remco On Jan 28, 2008 4:10 PM, <[EMAIL PROTECTED]> wrote: > Hi pythoners. > > I am generating strings of length n, randomly from the symbols > > +-/*0123456789 > > What would be the 'sensible' way of transforming the string, for example > changing '3++8' into 3+8 > or '3++--*-9' into '3+-9' such that eval(string) will always return a > number? > > in cases where multiple symbols conflict in meaning (as '3++--*-9' the > earliest valid symbols in the sequence should be preserved > > so for example, > > '3++*/-9' = 3+-9 > '45--/**/+7' = 45-+7 > '55/-**+-6**' = 55/-6 > > ...that is, unless there is a canonical method for doing this that does > something else instead.. > > > this sounds like homework. It's not. I like making problems up and it's a > slow work day. So, as an aside, there is no real reason I want to do this, > nor other problem to solve, nor other background to what I'm trying to > achieve ;) other than twiddling with python. > > Matt. > > > > This message and any attachments (the "message") is > intended solely for the addressees and is confidential. > If you receive this message in error, please delete it and > immediately notify the sender. Any use not in accord with > its purpose, any dissemination or disclosure, either whole > or partial, is prohibited except formal approval. The internet > can not guarantee the integrity of this message. > BNP PARIBAS (and its subsidiaries) shall (will) not > therefore be liable for the message if modified. > Do not print this message unless it is necessary, > consider the environment. > >- > > Ce message et toutes les pieces jointes (ci-apres le > "message") sont etablis a l'intention exclusive de ses > destinataires et sont confidentiels. Si vous recevez ce > message par erreur, merci de le detruire et d'en avertir > immediatement l'expediteur. Toute utilisation de ce > message non conforme a sa destination, toute diffusion > ou toute publication, totale ou partielle, est interdite, sauf > autorisation expresse. L'internet ne permettant pas > d'assurer l'integrite de ce message, BNP PARIBAS (et ses > filiales) decline(nt) toute responsabilite au titre de ce > message, dans l'hypothese ou il aurait ete modifie. > N'imprimez ce message que si necessaire, > pensez a l'environnement. > -- > http://mail.python.org/mailman/listinfo/python-list > -- http://mail.python.org/mailman/listinfo/python-list
