Re: Overriding "__setattr__" of a module - possible?

[Gabriel Genellina]

En Wed, 16 Jun 2010 19:56:39 -0300, Ian Kelly   
escribió:



On Wed, Jun 16, 2010 at 3:38 PM, John Nagle  wrote:

That just leaves things in a state where even "sys" and "import"
are undefined.


Say what?  It works fine for me.


import proxy_mod
proxy_mod.f()

1

proxy_mod.a = 2

setting a=2

proxy_mod.f()

2

proxy_mod.sys




It *mostly* works, but not always. Try this function:

def g(x):
global a
print 'global a -> ', x
a = x

py> import fake # ModuleProxy stuff
py> fake.f()
1
py> fake.a = 3
setting a=3
py> fake.f()
3
py> fake.g(8)
global a ->  8
py> fake.f()
8
py> fake.a
8

Note the fake.g(8) call: __setattr__ wasn't called.
If the OP wants to trace assignments to global variables, this becomes a  
problem.


A function defined in a module holds a reference to the module's __dict__  
in its func_globals attribute. Getting and setting global variables goes  
directly to this dictionary, and does not use the module object at all.


Even worse, the LOAD_GLOBAL/STORE_GLOBAL opcodes (which implement getting  
and setting global variables) assume func_globals is a true dictionary and  
bypass any overriden __getitem__/__setitem__ methods (an optimization,  
surely). I'm afraid it will be hard to intercept global variable usage in  
these circumstances.


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Re: Overriding "__setattr__" of a module - possible?

[Alf P. Steinbach]

* Gabriel Genellina, on 17.06.2010 09:25:

En Wed, 16 Jun 2010 19:56:39 -0300, Ian Kelly 
escribió:


On Wed, Jun 16, 2010 at 3:38 PM, John Nagle  wrote:

That just leaves things in a state where even "sys" and "import"
are undefined.


Say what? It works fine for me.


import proxy_mod
proxy_mod.f()

1

proxy_mod.a = 2

setting a=2

proxy_mod.f()

2

proxy_mod.sys




It *mostly* works, but not always. Try this function:

def g(x):
global a
print 'global a -> ', x
a = x

py> import fake # ModuleProxy stuff
py> fake.f()
1
py> fake.a = 3
setting a=3
py> fake.f()
3
py> fake.g(8)
global a -> 8
py> fake.f()
8
py> fake.a
8

Note the fake.g(8) call: __setattr__ wasn't called.
If the OP wants to trace assignments to global variables, this becomes a
problem.

A function defined in a module holds a reference to the module's
__dict__ in its func_globals attribute. Getting and setting global
variables goes directly to this dictionary, and does not use the module
object at all.

Even worse, the LOAD_GLOBAL/STORE_GLOBAL opcodes (which implement
getting and setting global variables) assume func_globals is a true
dictionary and bypass any overriden __getitem__/__setitem__ methods (an
optimization, surely). I'm afraid it will be hard to intercept global
variable usage in these circumstances.


Great exposition.

But who would have thunk that Python *isn't dynamic enough*? :-)


Cheers,

- Alf

--
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Re: basic doubt

[Gabriel Genellina]

En Thu, 17 Jun 2010 02:06:54 -0300, madhuri vio   
escribió:



def h(self,event):
handle = open("myco.fasta","r")
for seq_record in SeqIO.parse(handle, "fasta"):
 messenger_rna = coding_myco.fasta.transcribe()
 han1 = open("mycorna.fasta","wU")
 han1.close()
 return self.messenger_rna


the error is...

File "/usr/lib/python2.6/lib-tk/Tkinter.py", line 1413, in __call__
return self.func(*args)
TypeError: h() takes exactly 2 arguments (0 given)

 ia m unable to debug...i am stuck


This is just a guess, but looks like your h function is a plain function,  
not a method, so it doesn't take a "self" parameter. Also, you are  
probably using it in some place where the callback doesn't receive any  
additional arguments (like a Button command).

Try with def f(): ...
If it doesn't work, show us the part where h is used.

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Communicating with a program using subprocess

[Laurent Verweijen]

I have a file called increment.py as follows: 

#!/usr/bin/python
n = 0
while True:
n = int(raw_input(n)) + 1

This is easy to understand, but I want to pipe it's input/output
by another python program. (I will show what I am doing on the
console to test it)

>>> from subprocess import *
>>> p = Popen(["python", "increment.py"], stdin=PIPE, stdout=PIPE)
>>> p.communicate("5")
Traceback (most recent call last):
  File "increment.py", line 4, in 
n = int(raw_input(n)) + 1
EOFError: EOF when reading a line
('06', None)
>>> p.communicate("7")
Traceback (most recent call last):
  File "", line 1, in 
  File "/usr/lib/python2.6/subprocess.py", line 701, in communicate
return self._communicate(input)
  File "/usr/lib/python2.6/subprocess.py", line 1184, in _communicate
self.stdin.flush()
ValueError: I/O operation on closed file

The problem is that I want to use communicate multiple times
before closing the file.

How could I achieve this

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Re: Overriding "__setattr__" of a module - possible?

[Gabriel Genellina]

En Thu, 17 Jun 2010 04:52:48 -0300, Alf P. Steinbach   
escribió:



* Gabriel Genellina, on 17.06.2010 09:25:

En Wed, 16 Jun 2010 19:56:39 -0300, Ian Kelly 
escribió:


On Wed, Jun 16, 2010 at 3:38 PM, John Nagle  wrote:

That just leaves things in a state where even "sys" and "import"
are undefined.


Say what? It works fine for me.


import proxy_mod
proxy_mod.f()

1

proxy_mod.a = 2

setting a=2

proxy_mod.f()

2

proxy_mod.sys




It *mostly* works, but not always. Try this function:

def g(x):
global a
print 'global a -> ', x
a = x

py> import fake # ModuleProxy stuff
py> fake.f()
1
py> fake.a = 3
setting a=3
py> fake.f()
3
py> fake.g(8)
global a -> 8
py> fake.f()
8
py> fake.a
8

Note the fake.g(8) call: __setattr__ wasn't called.
If the OP wants to trace assignments to global variables, this becomes a
problem.

A function defined in a module holds a reference to the module's
__dict__ in its func_globals attribute. Getting and setting global
variables goes directly to this dictionary, and does not use the module
object at all.

Even worse, the LOAD_GLOBAL/STORE_GLOBAL opcodes (which implement
getting and setting global variables) assume func_globals is a true
dictionary and bypass any overriden __getitem__/__setitem__ methods (an
optimization, surely). I'm afraid it will be hard to intercept global
variable usage in these circumstances.


Great exposition.

But who would have thunk that Python *isn't dynamic enough*? :-)


Yep... There are other examples too (e.g. the print statement in 2.x  
bypasses sys.stdout.write; see also a recent thread "Which objects are  
expanded by double-star ** operator?")


Most of them seem to be speed optimizations, some might be considered  
subtle bugs. But in this case (global variable references) speed is so  
critical than even the dict lookup is inlined; the code in ceval.c says:


/* Inline the PyDict_GetItem() calls.
WARNING: this is an extreme speed hack.
Do not try this at home. */

Python is dynamic but not so much as to make it crawl like a snail...

--
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Re: Overriding "__setattr__" of a module - possible?

[Fuzzyman]

On Jun 17, 10:29 am, "Gabriel Genellina" 
wrote:
> En Thu, 17 Jun 2010 04:52:48 -0300, Alf P. Steinbach   
> escribió:
>
> > But who would have thunk that Python *isn't dynamic enough*? :-)
>
> Yep... There are other examples too (e.g. the print statement in 2.x  
> bypasses sys.stdout.write;


What do you mean by this? The print statement in 2.x does *not* bypass
sys.stdout. It may use other methods besides write (writeln perhaps)
but you can *definitely* override sys.stdout to capture the output
from print statements.

Michael Foord


> see also a recent thread "Which objects are  
> expanded by double-star ** operator?")
>
> Most of them seem to be speed optimizations, some might be considered  
> subtle bugs. But in this case (global variable references) speed is so  
> critical than even the dict lookup is inlined; the code in ceval.c says:
>
> /* Inline the PyDict_GetItem() calls.
> WARNING: this is an extreme speed hack.
> Do not try this at home. */
>
> Python is dynamic but not so much as to make it crawl like a snail...
>
> --
> Gabriel Genellina

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List of lists surprising behaviour

[candide]

Let's the following code :

>>> t=[[0]*2]*3
>>> t
[[0, 0], [0, 0], [0, 0]]
>>> t[0][0]=1
>>> t
[[1, 0], [1, 0], [1, 0]]

Rather surprising, isn't it ? So I suppose all the subarrays reférence 
the same array :


>>> id(t[0]), id(t[1]), id(t[2])
(3077445996L, 3077445996L, 3077445996L)
>>>


So what is the right way to initialize to 0 a 2D array ? Is that way 
correct  :



>>> t=[[0 for _ in range(2)] for _ in range(3)]

It seems there is no more trouble now :

>>> t
[[0, 0], [0, 0], [0, 0]]
>>> t[0][0]=1
>>> t
[[1, 0], [0, 0], [0, 0]]
>>>

Correct ?
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Re: How do I fix this test so it runs on Windows? (it uses tzset)

[Chris Withers]

Nobody wrote:

On Wed, 16 Jun 2010 16:30:02 +0100, Chris Withers wrote:

I'd like to make test_non_gmt_timezone at the bottom of 
https://...

run on Windows, any suggestions?


MSVCRT has _tzset(), which understands the TZ environment variable.

http://msdn.microsoft.com/en-us/library/90s5c885%28VS.80%29.aspx

For whatever reason, tython's "time" module doesn't provide the tzset()
function on Windows. However, you should be able to use it via ctypes.


This sounds pretty heavyweight for a unit test.
I'm not even sure how I would do this ;-)

Where can I find an example?

...or better yet, does anyone have any alternative solutions?

Chris

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Re: List of lists surprising behaviour

[Lie Ryan]

On 06/17/10 20:21, candide wrote:
> Let's the following code :
> 
 t=[[0]*2]*3
 t
> [[0, 0], [0, 0], [0, 0]]
 t[0][0]=1
 t
> [[1, 0], [1, 0], [1, 0]]
> 
> Rather surprising, isn't it ? So I suppose all the subarrays reférence
> the same array :
> 
 id(t[0]), id(t[1]), id(t[2])
> (3077445996L, 3077445996L, 3077445996L)


Yep, you're right. They share the same subarray if you uses
multiplication to build the array.

> So what is the right way to initialize to 0 a 2D array ? Is that way
> correct  :
 t=[[0 for _ in range(2)] for _ in range(3)]

Right again. That's the way to go. Although if the elements are
immutable, you can create the innermost array by multiplication:

t=[[0]*2 for _ in range(3)]
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Re: List of lists surprising behaviour

[Matteo Landi]

Yes you are. List comprehension makes you create list of lists without
reference-sharing. You should also find a recipe about that on the
python cookbook.

On Thu, Jun 17, 2010 at 12:21 PM, candide  wrote:
> Let's the following code :
>
 t=[[0]*2]*3
 t
> [[0, 0], [0, 0], [0, 0]]
 t[0][0]=1
 t
> [[1, 0], [1, 0], [1, 0]]
>
> Rather surprising, isn't it ? So I suppose all the subarrays reférence the
> same array :
>
 id(t[0]), id(t[1]), id(t[2])
> (3077445996L, 3077445996L, 3077445996L)

>
>
> So what is the right way to initialize to 0 a 2D array ? Is that way correct
>  :
>
>
 t=[[0 for _ in range(2)] for _ in range(3)]
>
> It seems there is no more trouble now :
>
 t
> [[0, 0], [0, 0], [0, 0]]
 t[0][0]=1
 t
> [[1, 0], [0, 0], [0, 0]]

>
> Correct ?
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
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http://www.matteolandi.net/
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Could not import external source folder in Pydev

[Narendran]

Env info:
Python version:  '2.6.5 (r265:79063, Apr 16 2010, 13:57:41) \n[GCC
4.4.3]'
Eclipse version: Version: 3.5.2 Build id: M20100211-1343
PyDev version:  PyDev for Eclipse   1.5.7.2010050621
org.python.pydev.feature.feature.group
OS: Ubuntu 10.04

Problem:
I am trying to develop a module using web2py's DAL classes. To be able
to do it, I want to add web2py/gluon source folder as external source
folder to my project. Even after doing that, I am not able to get the
classes/packages in gluon directory in my dev env (auto-completion
doesn't happen; run fails.)

Can someone please let me know if there is any known issue/or if I am
going wrong somewhere? Thanks in advance for your help.

--
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Serializing functions

[Matteo Landi]

Some weeks ago, here on the mailing list I read about picloud[1], a
python library used for cloud-computing; I was impressed by its
simplicity, here is an example:

>>>import cloud
>>>def square(x):
...  return x * x
>>>cloud.call(square, 10)
>>>cloud.result()
100

So, I tried to figure out how to achieve the same result, i.e. define a
local generic function and send it somewhere for remote execution, and
the get the result back.
So I thought about serialization (pickle): I made a few tries and it
seemed to work.. but I was wrong, because I never tried to load pickled
data from another session different from the one used to pickle data
itself. If you try and pickle a function, it is not pickled as a whole,
indeed, once you unpickle it, it will raise an exception telling you
that the target function was not found in the current module.

So I'm here, with nothing in my hands; how would you implement this?

Thanks in advance.

[1] http://www.picloud.com/

-- 
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http://www.matteolandi.net

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Re: a +b ?

[David Robinow]

On Wed, Jun 16, 2010 at 11:34 PM, Aahz  wrote:
> In article ,
> James Mills   wrote:
...
>>What in particular do you _not_ enjoy about using map/reduce (and
>>possibly other functional features of the Python programing language) ?
>
> map() never felt particularly Pythonic, especially the way it works with
> None as the function combined with multiple arguments.  I can't explain
> why I loathe reduce() -- it just doesn't fit my brain.
 FWIW, I don't know what reduce() does. Every time I see it I have to
look it up.
I think I understand map() but probably wouldn't use it (Note: I
haven't actually written any code in a few years, being retired, or
unemployed, or something)
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Re: GUIs - A Modest Proposal

[Grant Edwards]

On 2010-06-16, Matt  wrote:
> On 06/05/2010 09:22 PM, ant wrote:
>
>>  PyQt is tied to one platform.
>
>
> Several posters have asked for support for or clarification of this 
> claim of yours.

Let me guess...

The one platform it's tied to is Qt?

-- 
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  at   CONCERN for REVERAND MOON's
  gmail.comlegal difficulties!!
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Re: List of lists surprising behaviour

[Boris Borcic]

candide wrote:


So what is the right way to initialize to 0 a 2D array ? Is that way
correct :


 >>> t=[[0 for _ in range(2)] for _ in range(3)]


That's overkill :) You can skip the inner loop by using a list display, eg

t=[[0,0] for _ in range(3)]



It seems there is no more trouble now :

 >>> t
[[0, 0], [0, 0], [0, 0]]
 >>> t[0][0]=1
 >>> t
[[1, 0], [0, 0], [0, 0]]
 >>>

Correct ?



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Re: Serializing functions

[Bruno Desthuilliers]

Matteo Landi a écrit :

Some weeks ago, here on the mailing list I read about picloud[1], a
python library used for cloud-computing; I was impressed by its
simplicity, here is an example:


import cloud
def square(x):

...  return x * x

cloud.call(square, 10)
cloud.result()

100

So, I tried to figure out how to achieve the same result, i.e. define a
local generic function and send it somewhere for remote execution, and
the get the result back.
So I thought about serialization (pickle): I made a few tries and it
seemed to work.. but I was wrong, because I never tried to load pickled
data from another session different from the one used to pickle data
itself. If you try and pickle a function, it is not pickled as a whole,
indeed, once you unpickle it, it will raise an exception telling you
that the target function was not found in the current module.

So I'm here, with nothing in my hands; how would you implement this?


Hint found on picloud's website:

"""
PiCloud's programming library, cloud, automatically transfers the 
necessary source code, byte code, execution state, and data to run your 
function on our cluster.

"""

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Goals,watch the World Cup .. mondial 2010 Online

[mondial worldcup2010]

Goals,watch the World Cup .. mondial 2010 Online
http://www.echance.info/fifa2010
http://www.echance.info/sopcast-en
http://www.echance.info/sopcast-ar
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كيف تحصل على لاب توب جائزة

[mondial worldcup2010]

How to get a laptop gift
http://echance.info/laptop.htm
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Re: Serializing functions

[Paul Rubin]

Matteo Landi  writes:
> If you try and pickle a function, it is not pickled as a whole,
> indeed, once you unpickle it, it will raise an exception telling you
> that the target function was not found in the current module.
>
> So I'm here, with nothing in my hands; how would you implement this?

Use marshal rather than pickle.  Note that requires both ends to be
running the same python version.  Be aware of the obvious security
issues of running code that came from remote machine, either because the
remote machine itself may be untrusted or compromised, or because the
network between the two machines may be compromised (remote machine is
being spoofed or commnications are being modified).
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Re: gui doubt

[Tim Chase]

On 06/17/2010 01:04 AM, Stephen Hansen wrote:

On 6/16/10 10:40 PM, madhuri vio wrote:

if i want to create a button
which performs the transcription of dna to rna
using tkinter in a gui...
can u give me the method...


You can not possibly be serious.


Oh, it's not that bad

[dna2rna.py]##
import Tkinter as tk

root = tk.Tk()
root.title("dna2rna")

def translate():
  from tkMessageBox import showinfo
  showinfo("Translate",
"Do some translating here.\n"
"Maybe in another thread so the GUI doesn't stall."
)
  # do your actual work here

tk.Button(
  root,
  text="Translate!",
  command=translate
  ).pack()
root.mainloop()
##

Now all one needs to do is fill in the blanks in the Translate 
call to do the actual work...an exercise left for the 
professional in the field. ;-)   I suspect the GUI may need to be 
a bit more complex than that which might lead to wanting a more 
object-oriented code-base, but I leave that too as an exercise 
for the reader.


-tkc



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Re: Serializing functions

[Matteo Landi]

On Thu, 2010-06-17 at 07:37 -0700, Paul Rubin wrote:
> Matteo Landi  writes:
> > If you try and pickle a function, it is not pickled as a whole,
> > indeed, once you unpickle it, it will raise an exception telling you
> > that the target function was not found in the current module.
> >
> > So I'm here, with nothing in my hands; how would you implement this?
> 
> Use marshal rather than pickle.  Note that requires both ends to be

I could be wrong, but it seems functions are not marshable objects, is
it right?

> running the same python version.  Be aware of the obvious security
> issues of running code that came from remote machine, either because the
> remote machine itself may be untrusted or compromised, or because the
> network between the two machines may be compromised (remote machine is
> being spoofed or commnications are being modified).

-- 
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RE: gui doubt

[Andreas Tawn]

> On 06/17/2010 01:04 AM, Stephen Hansen wrote:
> > On 6/16/10 10:40 PM, madhuri vio wrote:
> >> if i want to create a button
> >> which performs the transcription of dna to rna
> >> using tkinter in a gui...
> >> can u give me the method...
> >
> > You can not possibly be serious.
> 
> Oh, it's not that bad
> 
> [dna2rna.py]##
> import Tkinter as tk
> 
> root = tk.Tk()
> root.title("dna2rna")
> 
> def translate():
>from tkMessageBox import showinfo
>showinfo("Translate",
>  "Do some translating here.\n"
>  "Maybe in another thread so the GUI doesn't stall."
>  )
># do your actual work here
> 
> tk.Button(
>root,
>text="Translate!",
>command=translate
>).pack()
> root.mainloop()
> ##
> 
> Now all one needs to do is fill in the blanks in the Translate
> call to do the actual work...an exercise left for the
> professional in the field. ;-)   I suspect the GUI may need to be
> a bit more complex than that which might lead to wanting a more
> object-oriented code-base, but I leave that too as an exercise
> for the reader.
> 
> -tkc

Seems like a simple problem... or am I missing something?

def translate():
   return "dna".replace("d", "r")

Cheers,

Drea

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Re: Serializing functions

[Paul Rubin]

Matteo Landi  writes:
> I could be wrong, but it seems functions are not marshable objects, is
> it right?

Hmm, you're right, you can marshal code objects, but you can't marshal a
function directly.  It's been a while since I've used marshal and I
forgot how it works.  You might be able to concoct something around it,
but it could be messy.  It may be simplest to send the other side a
python source file that it can import.
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Re: Serializing functions

[Matteo Landi]

On Thu, 2010-06-17 at 07:37 -0700, Paul Rubin wrote:
> Matteo Landi  writes:
> > If you try and pickle a function, it is not pickled as a whole,
> > indeed, once you unpickle it, it will raise an exception telling you
> > that the target function was not found in the current module.
> >
> > So I'm here, with nothing in my hands; how would you implement this?
> 
> Use marshal rather than pickle.  Note that requires both ends to be

I could be wrong, but it seems functions are not marshable objects, is
it right?

> running the same python version.  Be aware of the obvious security
> issues of running code that came from remote machine, either because the
> remote machine itself may be untrusted or compromised, or because the
> network between the two machines may be compromised (remote machine is
> being spoofed or commnications are being modified).

-- 
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http://www.matteolandi.net

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Re: gui doubt

[Bruno Desthuilliers]

Andreas Tawn a écrit :

On 06/17/2010 01:04 AM, Stephen Hansen wrote:

On 6/16/10 10:40 PM, madhuri vio wrote:

if i want to create a button
which performs the transcription of dna to rna


(snip the GUI part)



Seems like a simple problem... or am I missing something?

def translate():
   return "dna".replace("d", "r")



!-)
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Re: Serializing functions

[Stephen Hansen]

On 6/17/10 6:23 AM, Matteo Landi wrote:
> itself. If you try and pickle a function, it is not pickled as a whole,
> indeed, once you unpickle it, it will raise an exception telling you
> that the target function was not found in the current module.

You can pickle functions-- and classes, instances, and such-- just fine.
If you're having specific difficulty with one instance of doing so, show
the actual code.

>>> def test(one):
... print one + 1
...
>>> import pickle
>>> outp = pickle.dumps(test)
>>> outp
'c__main__\ntest\np0\n.'
>>> fn = pickle.loads(outp)
>>> fn(1)
2

Now, complex stuff like classes and functions have to "live" in the same
place with pickle, and it does need the source to be available and
already imported, but it works fine.

If by "pickle a function" you mean, "take an arbitrary function and
pickle it into some random destination and have it by itself still be
enough to be executable", then no, pickle doesn't do that. To get that,
you'd have to distribute the source to the destination and import it
before-hand.

That or do some crazy-complicated sort of code object marshalling and
manipulation on the other side. I have no idea where to even begin in
that situation (hw do you turn a code object into something you can
actually pass arguments to, hmm? I only know how to 'exec' a bare code
object)

-- 

   Stephen Hansen
   ... Also: Ixokai
   ... Mail: me+list/python (AT) ixokai (DOT) io
   ... Blog: http://meh.ixokai.io/



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Re: gui doubt

[Tim Chase]

On 06/17/2010 10:07 AM, Andreas Tawn wrote:

On 6/16/10 10:40 PM, madhuri vio wrote:

which performs the transcription of dna to rna

[snip]

Seems like a simple problem... or am I missing something?

def translate():
return "dna".replace("d", "r")


And I understand people in bioinformatics get paid big 
money...for that!? ;-)


-tkc


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Re: gui doubt

[Steven W. Orr]

On 06/17/10 01:40, quoth madhuri vio:
> if i want to create a button
> which performs the transcription of dna to rna
> using tkinter in a gui...
> can u give me the method...
> 
> -- 
> madhuri :)
> 

Dear Madasahatter. You need to read the description below on how to properly
implement and use the unsubscribe button. After use, please take a piece of
cardboard and hand it around your neck to announce your accomplishment. The
algorithm below may need to be translated into python, but I would expect that
this would be the easiest part of the problem. We all wish you the best of
luck in your new venture as village idiot. In the future, please let the FBI
know if you have any problems.

From: "Dr. Bryan Bledsoe" 
To: "prehospitalcare List Member"  
Subject: [prehospitalcare] How To Remove Yourself From The List
Date: Sat, 10 Aug 2002 20:55:52 -0500
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Phil:

You are WRONG.  Here is how to unsubscribe from prehospitalc...@emsvillage.com:
How to unsubscribe (as you requested)

First, ask your Internet Provider to mail you an Unsubscribing
Kit. Then follow these directions. The kit will most likely be
the standard no-fault type. Depending on requirements,
System A and/or System B can be used. When operating System A,
depress lever and a plastic dalkron unsubscriber will be dispensed
through the slot immediately underneath. When you have fastened the
adhesive lip, attach connection marked by the large "X" outlet
hose. Twist the silver- coloured ring one inch below the connection
point until you feel it lock.

The kit is now ready for use. The Cin-Eliminator is activated by the
small switch on the lip. When securing, twist the ring back to its
initial condition, so that the two orange lines meet. Disconnect.

Place the dalkron unsubscriber in the vacuum receptacle to the
rear. Activate by pressing the blue button.

The controls for System B are located on the opposite side. The red
release switch places the Cin-Eliminator into position; it can be
adjusted manually up or down by pressing the blue manual release
button. The opening is self-adjusting. To secure after use, press the
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You may log off if the green exit light is on over the evaporator. If
the red light is illuminated, one of the Cin-Eliminator requirements
has not been properly implemented.

Press the "List Guy" call button on the right of the evaporator. He
will secure all facilities from his control panel.

To use the Auto-Unsub, first undress and place all your clothes in
the clothes rack. Put on the velcro slippers located in the cabinet
immediately below. Enter the shower, taking the entire kit with
you. On the control panel to your upper right upon entering you will
see a "Shower seal" button.

Press to activate. A green light will then be illuminated immediately
below. On the intensity knob, select the desired setting. Now depress
the Auto-Unsub activation lever.

Bathe normally.

The Auto-Unsub will automatically go off after three minutes unless
you activate the "Manual off" override switch by flipping it up. When
you are ready to leave, press the blue "Shower seal" release
button. The door will open and you may leave. Please remove the
velcro slippers and place them in their container.

If you prefer the ultrasonic log-off mode, press the indicated blue
button. When the twin panels open, pull forward by rings A & B. The
knob to the left, just below the blue light, has three settings, low,
medium or high. For normal use, the medium setting is suggested.

After these settings have been made, you can activate the device by
switching to the "ON" position the clearly marked red switch. If
during the unsubscribing operation you wish to change the settings,
place the "manual off" override switch in the "OFF" position. You may
now make the change and repeat the cycle. When the green exit light
goes on, you may log off and have lunch. Please close the door behind
you.




Bryan E. Bledsoe, DO, FACEP
Midlothian, Texas

All outgoing email scanned by Norton Antivirus and guaranteed
"virus free" or your money back.

- Original Message -
From: Philip L. Hayes
To: prehospitalcare List Member
Sent: Saturday, August 10, 2002 7:50 PM
Subject: [prehospitalcare] How To Remove Yourself From The List

Hi Everybody-

To remove yourself from the list serv, simply follow
the instructions at the bottom of every e-mail. Sending
an unsubscribe or remove command to the list will not
do it.

Phil Hayes
EMS Village Support



-Original Message-
From: prehospitalc...@emsv

Re: Serializing functions

[Matteo Landi]

On Thu, 2010-06-17 at 08:31 -0700, Stephen Hansen wrote:
> On 6/17/10 6:23 AM, Matteo Landi wrote:
> > itself. If you try and pickle a function, it is not pickled as a whole,
> > indeed, once you unpickle it, it will raise an exception telling you
> > that the target function was not found in the current module.
> 
> You can pickle functions-- and classes, instances, and such-- just fine.
> If you're having specific difficulty with one instance of doing so, show
> the actual code.
> 
> >>> def test(one):
> ... print one + 1
> ...
> >>> import pickle
> >>> outp = pickle.dumps(test)
> >>> outp
> 'c__main__\ntest\np0\n.'
> >>> fn = pickle.loads(outp)
> >>> fn(1)
> 2
> 
> Now, complex stuff like classes and functions have to "live" in the same
> place with pickle, and it does need the source to be available and
> already imported, but it works fine.
> 
> If by "pickle a function" you mean, "take an arbitrary function and
> pickle it into some random destination and have it by itself still be
> enough to be executable", then no, pickle doesn't do that. To get that,
> you'd have to distribute the source to the destination and import it
> before-hand.

This is the problem, and I excuse me if I ain't been clear enough while
showing it inside my previous email.

> 
> That or do some crazy-complicated sort of code object marshalling and
> manipulation on the other side. I have no idea where to even begin in
> that situation (hw do you turn a code object into something you can
> actually pass arguments to, hmm? I only know how to 'exec' a bare code
> object)
> 

So it seems one should go for sending the function and the module with
its definition in order to make the remote side able to execute it.

I'm curious to see how picloud is able to discover the needed modules,
sources etc etc to run the function specified inside picloud.call(); it
seems not an easy task.

-- 
Matteo Landi
http://www.matteolandi.net

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Re: Serializing functions

[Andreas Löscher]

Am Donnerstag, den 17.06.2010, 08:18 -0700 schrieb Paul Rubin:
> Matteo Landi  writes:
> > I could be wrong, but it seems functions are not marshable objects, is
> > it right?
> 
> Hmm, you're right, you can marshal code objects, but you can't marshal a
> function directly.  It's been a while since I've used marshal and I
> forgot how it works.  You might be able to concoct something around it,
> but it could be messy.  It may be simplest to send the other side a
> python source file that it can import.

There was a similar thread a while ago.

You can marshal the functions code object and create a new function on
the remote side using this code object.

>>> import marshal
>>> def spam(): pass

now marshal the code object

>>> s = marshal.dumps(spam.func_code)

On the remote side:

>>> import marshal
>>> import types
>>> code = marshal.loads(s)
>>> spam = types.FunctionType(code, globals())

This works as long as you are using byte code compatible Versions on
both side. The creation of functions has also some optional arguments
you must be aware of, in order to get the result you want. 

Look at help(types.FunctionType) for further information.



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Re: Serializing functions

[Andreas Löscher]

Am Donnerstag, den 17.06.2010, 18:03 +0200 schrieb Andreas Löscher:
> Am Donnerstag, den 17.06.2010, 08:18 -0700 schrieb Paul Rubin:
> > Matteo Landi  writes:
> > > I could be wrong, but it seems functions are not marshable objects, is
> > > it right?
> > 
> > Hmm, you're right, you can marshal code objects, but you can't marshal a
> > function directly.  It's been a while since I've used marshal and I
> > forgot how it works.  You might be able to concoct something around it,
> > but it could be messy.  It may be simplest to send the other side a
> > python source file that it can import.
> 
> There was a similar thread a while ago.
> 

Ah I found it:
Search for:

"Object serialization: transfer from a to b (non-implemented code on b)"

 in this mailing list.

Is there a good way to link a former thread?


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Efficiency/style issues of import vs. from import , ...

[python]

Are there any efficiency or style guidelines regarding the choice
of "import " vs. "from  import , ..."?

If one only needs to import a few names from a module, are there
specific benefits to explictly importing these names?

My understanding is that both forms of the import command require
the entire module to be processed.

If this comes down purely to preference, are there PEP 8-like
standards regarding which approach to use when?

Thanks,
Malcolm
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Re: Upgrading from Python 2.6.5 w.r.t. matplotlib/numpy?

[Robert Kern]

On 6/17/10 12:24 AM, Stephen Hansen wrote:

On 6/16/10 10:18 PM, Mark Lawrence wrote:

I'm like to go direct to Python 3.1 if possible, but if necessary I'll
happily use Python 2.7 as an interim measure. However I'm uncertain as
to the status of matplotlib and its dependency on numpy.  I've tried
googling their development mailing lists but don't really understand
what the current situation is.


Asking those mailing lists is probably the best course.


Could somebody please recommend whether
I take the direct or indirect route to Python 3.1.  FWIW I'm on Windows
Vista.


Numpy isn't available for 3.1 yet. IIUC, its not That Terribly Awfully
Long Away (meaning, some indeterminate time probably counted in months
and not years), but its not there yet.


I believe it builds and passes most tests. Maybe not on Vista, though.

--
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
 that is made terrible by our own mad attempt to interpret it as though it had
 an underlying truth."
  -- Umberto Eco

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Re: gui doubt

[Robert Kern]

On 6/17/10 10:38 AM, Tim Chase wrote:

On 06/17/2010 10:07 AM, Andreas Tawn wrote:

On 6/16/10 10:40 PM, madhuri vio wrote:

which performs the transcription of dna to rna

[snip]

Seems like a simple problem... or am I missing something?

def translate():
return "dna".replace("d", "r")


And I understand people in bioinformatics get paid big money...for
that!? ;-)


Actually, the full method is a lot more complicated:

def translate(dna):
return dna.replace('T', 'U')

--
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
 that is made terrible by our own mad attempt to interpret it as though it had
 an underlying truth."
  -- Umberto Eco

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Re: Serializing functions

[Robert Kern]

On 6/17/10 8:23 AM, Matteo Landi wrote:

Some weeks ago, here on the mailing list I read about picloud[1], a
python library used for cloud-computing; I was impressed by its
simplicity, here is an example:


import cloud
def square(x):

...  return x * x

cloud.call(square, 10)
cloud.result()

100

So, I tried to figure out how to achieve the same result, i.e. define a
local generic function and send it somewhere for remote execution, and
the get the result back.
So I thought about serialization (pickle): I made a few tries and it
seemed to work.. but I was wrong, because I never tried to load pickled
data from another session different from the one used to pickle data
itself. If you try and pickle a function, it is not pickled as a whole,
indeed, once you unpickle it, it will raise an exception telling you
that the target function was not found in the current module.

So I'm here, with nothing in my hands; how would you implement this?


PiCloud's client library is LGPLed. Go take a look for yourself. It's pretty 
nifty.

[Disclosure: My employer, Enthought, has partnered with PiCloud to provide our 
Enthought Python Distribution to PiCloud users. However, I say that it's nifty 
purely because it is.]


--
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
 that is made terrible by our own mad attempt to interpret it as though it had
 an underlying truth."
  -- Umberto Eco

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Re: Efficiency/style issues of import vs. from import , ...

[Stephen Hansen]

On 6/17/10 9:12 AM, pyt...@bdurham.com wrote:
> Are there any efficiency or style guidelines regarding the choice
> of "import " vs. "from  import , ..."?

There are no legitimate efficiency issues. In theory, module.blah is
slightly slower then blah, but that "slightly" is largely irrelevant in
globals. If you need to do module.blah a lot in a loop, you want to
re-bind it into a local anyways before that loop if performance starts
mattering that much.

Style wise, the only guideline is, "from  import *" is often
(but not always) bad. It pollutes the namespace, making it difficult to
know exactly what's defined and where it is defined. Multiple "import
*"'s are especially bad.

Explicitly importing certain names is perfectly fine. Its clear and
explicit. Someone seeing, "MyRandomClass" can search in the code and
they'll find that import and know precisely where to go to look for it.

> If one only needs to import a few names from a module, are there
> specific benefits to explictly importing these names?

Clarity, sometimes. There is no general rule here though. It depends on
the structure and layout. Its a case-by-case situation; is it more clear
to your natural reading to have 'module.MyRandomThing' or just
'MyRandomThing' in your code?

An example: let's say you have a "handlers" module containing certain...
uh.. handlers.. you have defined for your application.

You could either:

import handlers

Or:

from handlers import MyHTTPHandler, MySMTPHandler, MyNNTPHandler

In this case, I'd consider it possible that in code usage, its entirely
sufficient to call "MyHTTPHandler" and have it be clear and
understandable for future non-you coders. "handlers.MyHTTPHandler" is
slightly more explicit, but due to the naming and structure of this
specific code, redundant as well. That may not always hold true.

Now, this is all IMHO: the style guide does not define any 'guidelines'
on this, except that its okay to use "from ... import ..." to pull in
classes and (implicitly) constants, and despite how the rules say 'one
module per line' its OK to pull in more then one name -from- a module at
once.

> My understanding is that both forms of the import command require
> the entire module to be processed.

Yes.

"from  import " is just a shortcut for:

import 
 = .

-- 

   Stephen Hansen
   ... Also: Ixokai
   ... Mail: me+list/python (AT) ixokai (DOT) io
   ... Blog: http://meh.ixokai.io/



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super() woes (n00b)

[Deadly Dirk]

I cannot get right the super() function:
Python 3.1.1+ (r311:74480, Nov  2 2009, 14:49:22) 
[GCC 4.4.1] on linux2
Type "copyright", "credits" or "license()" for more information.
 No Subprocess 
>>> class P:
def __init__(__class__,self):
print("I am a member of class P")


>>> class C(P):
def __init__(self):
super().__init__(self)
print("I am a member of class C")



class P:
def __init__(self):
print("I am a member of class P")

class C(P):
def __init__(self):
super().__init__(self)
print("I am a member of class C")

x=C()

That is more or less the text from the "Quick Python Book". What am I 
doing wrong?

-- 
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as if the savages weren't dangerous enough already.
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Re: Efficiency/style issues of import vs. from import , ...

[Ethan Furman]

Stephen Hansen wrote:

On 6/17/10 9:12 AM, pyt...@bdurham.com wrote:

Now, this is all IMHO: the style guide does not define any 'guidelines'
on this, except that its okay to use "from ... import ..." to pull in
classes and (implicitly) constants, and despite how the rules say 'one
module per line' its OK to pull in more then one name -from- a module at
once.


What do you mean by "(implicitly) constants"?



My understanding is that both forms of the import command require
the entire module to be processed.


Yes.

"from  import " is just a shortcut for:

import 
 = .



There should also be a third line:
  del 

~Ethan~
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Re: super() woes (n00b)

[Deadly Dirk]

On Thu, 17 Jun 2010 16:36:10 +, Deadly Dirk wrote:

> I cannot get right the super() function: Python 3.1.1+ (r311:74480, Nov 
> 2 2009, 14:49:22) [GCC 4.4.1] on linux2
> Type "copyright", "credits" or "license()" for more information.  No
> Subprocess 
 class P:
> def __init__(__class__,self):
> print("I am a member of class P")
> 
> 
 class C(P):
> def __init__(self):
> super().__init__(self)
> print("I am a member of class C")
> 
> 
> 
> class P:
> def __init__(self):
> print("I am a member of class P")
> 
> class C(P):
> def __init__(self):
> super().__init__(self)
> print("I am a member of class C")
> 
> x=C()
> 
> That is more or less the text from the "Quick Python Book". What am I
> doing wrong?

I tried this, too:

>>> class C(P):
def __init__(self):
super(__class__).__init__(self)
print("I am a member of class C")


>>> x=C()
Traceback (most recent call last):
  File "", line 1, in 
x=C()
  File "", line 3, in __init__
super(__class__).__init__(self)
TypeError: must be type, not C
>>> 



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Re: Efficiency/style issues of import vs. from import , ...

[Stephen Hansen]

On 6/17/10 10:01 AM, Ethan Furman wrote:
> Stephen Hansen wrote:
>> On 6/17/10 9:12 AM, pyt...@bdurham.com wrote:
>>
>> Now, this is all IMHO: the style guide does not define any 'guidelines'
>> on this, except that its okay to use "from ... import ..." to pull in
>> classes and (implicitly) constants, and despite how the rules say 'one
>> module per line' its OK to pull in more then one name -from- a module at
>> once.
> 
> What do you mean by "(implicitly) constants"?

Quote, PEP-8:

 - Imports should usually be on separate lines, e.g.:

Yes: import os
 import sys

No:  import sys, os

  it's okay to say this though:

from subprocess import Popen, PIPE

It explicitly states later its entirely OK to import classes. It never
says anything else directly, except in the example given, it shows you
importing a constant. So, its giving implicit approval to that without
really directly saying anything about it.

>>> My understanding is that both forms of the import command require
>>> the entire module to be processed.
>>
>> Yes.
>>
>> "from  import " is just a shortcut for:
>>
>> import 
>>  = .
> 
> 
> There should also be a third line:
>   del 

You're right, I missed that.

-- 

   Stephen Hansen
   ... Also: Ixokai
   ... Mail: me+list/python (AT) ixokai (DOT) io
   ... Blog: http://meh.ixokai.io/



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Re: Overriding "__setattr__" of a module - possible?

[John Nagle]

On 6/17/2010 12:25 AM, Gabriel Genellina wrote:

Note the fake.g(8) call: __setattr__ wasn't called.
If the OP wants to trace assignments to global variables, this becomes a
problem.

A function defined in a module holds a reference to the module's
__dict__ in its func_globals attribute. Getting and setting global
variables goes directly to this dictionary, and does not use the module
object at all.

Even worse, the LOAD_GLOBAL/STORE_GLOBAL opcodes (which implement
getting and setting global variables) assume func_globals is a true
dictionary and bypass any overriden __getitem__/__setitem__ methods (an
optimization, surely). I'm afraid it will be hard to intercept global
variable usage in these circumstances.


   OK, thanks.  You can't actually replace "__setattr__" for
a module, and the "module as class" hack is iffy.  I didn't
really think this would work, but it was worth a try.

   I'm trying out a proof of concept implementation for a new
approach to safe threading.  It's somewhat similar in concept
to Alan Olsen's scheme.  The basic difference is that once
the program goes multi-thread, code objects and some other
bindings are locked down and become unchangeable.  Olsen
was climbing the walls trying to get the locking right for
the awful cases like redefining a function while another thread
is inside it.  I'm trying to lock out some of those cases.
If you do that, removing the GIL requires less pain than
Olsen experienced.

   The key idea is that the use cases for most of Python's
code dynamism are during setup and initialization.  You usually
don't change code once the program has gone into its heavy
parallel processing phase.  This suggests a practical compromise.

   More on this once I have something people can download and try.
I'm doing a test implementation in Python so people can try the
concept and see if it works in practice.  It won't go fast;
it's just to give a feel for what it would be like.

John Nagle

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Re: Efficiency/style issues of import vs. from import , ...

[Ethan Furman]

Stephen Hansen wrote:

On 6/17/10 10:01 AM, Ethan Furman wrote:

Stephen Hansen wrote:

On 6/17/10 9:12 AM, pyt...@bdurham.com wrote:

Now, this is all IMHO: the style guide does not define any 'guidelines'
on this, except that its okay to use "from ... import ..." to pull in
classes and (implicitly) constants, and despite how the rules say 'one
module per line' its OK to pull in more then one name -from- a module at
once.

What do you mean by "(implicitly) constants"?


Quote, PEP-8:

 - Imports should usually be on separate lines, e.g.:

Yes: import os
 import sys

No:  import sys, os

  it's okay to say this though:

from subprocess import Popen, PIPE

It explicitly states later its entirely OK to import classes. It never
says anything else directly, except in the example given, it shows you
importing a constant. So, its giving implicit approval to that without
really directly saying anything about it.



Thanks for the clarification -- I was reading it as constants being 
implicitly imported, and I knew that wasn't so!  ;)


~Ethan~
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Re: Efficiency/style issues of import vs. from import , ...

[Jack Diederich]

On Thu, Jun 17, 2010 at 12:58 PM, Stephen Hansen
 wrote:
> On 6/17/10 10:01 AM, Ethan Furman wrote:
>> Stephen Hansen wrote:
>>> On 6/17/10 9:12 AM, pyt...@bdurham.com wrote:
>>>
>>> Now, this is all IMHO: the style guide does not define any 'guidelines'
>>> on this, except that its okay to use "from ... import ..." to pull in
>>> classes and (implicitly) constants, and despite how the rules say 'one
>>> module per line' its OK to pull in more then one name -from- a module at
>>> once.
>>
>> What do you mean by "(implicitly) constants"?
>
> Quote, PEP-8:
>
>  - Imports should usually be on separate lines, e.g.:
>
>        Yes: import os
>             import sys
>
>        No:  import sys, os
>
>      it's okay to say this though:
>
>        from subprocess import Popen, PIPE
>
> It explicitly states later its entirely OK to import classes. It never
> says anything else directly, except in the example given, it shows you
> importing a constant. So, its giving implicit approval to that without
> really directly saying anything about it.

You want to import a name that is itself a namespace; preferably a
module or package and sometimes a class.  Importing constants can lead
to trouble.  ex/

from settings import DEBUG
if DEBUG: log('debug is on!')

The value of the flag gets fetched at import time.  If code in another
module updates settings.DEBUG later your module won't see it. ditto
for exceptions.

-Jack
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Re: Efficiency/style issues of import vs. from import , ...

[Ethan Furman]

Jack Diederich wrote:

You want to import a name that is itself a namespace; preferably a
module or package and sometimes a class.  Importing constants can lead
to trouble.  ex/

from settings import DEBUG
if DEBUG: log('debug is on!')

The value of the flag gets fetched at import time.  If code in another
module updates settings.DEBUG later your module won't see it. ditto
for exceptions.

-Jack


The idea behind constants is that they are... um... constant.  ;)  I 
imagine exceptions don't get changed often either.  (At least, I never 
change mine.)


If you have a setting that may change, don't call it a constant and name 
it accordingly.


~Ethan~
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Re: Efficiency/style issues of import vs. from import , ...

[Stephen Hansen]

On 6/17/10 10:22 AM, Jack Diederich wrote:
> On Thu, Jun 17, 2010 at 12:58 PM, Stephen Hansen
>> It explicitly states later its entirely OK to import classes. It never
>> says anything else directly, except in the example given, it shows you
>> importing a constant. So, its giving implicit approval to that without
>> really directly saying anything about it.
> 
> You want to import a name that is itself a namespace; preferably a
> module or package and sometimes a class.  Importing constants can lead
> to trouble.  ex/
> 
> from settings import DEBUG
> if DEBUG: log('debug is on!')
> 
> The value of the flag gets fetched at import time.  If code in another
> module updates settings.DEBUG later your module won't see it. ditto
> for exceptions.

That argument is invalid on its face; a constant, by definition, is not
to be modified. The convention (recently adopted officially by PEP-8) of
ALL_CAPS makes this promise: this is a static piece of data.

That its possible for misbehaving code to change it due to Python's lax
nature doesn't mean you should organize or write your code in such a way
to take that into account. People can shoot themselves in the foot.

If people do stupid things after writing code that makes promises, stuff
that relies upon the explicit promises made may fail, and that's their
own dumb fault.

And the only time someone is going to go 'change' an exception that
lives in the top-level of some other module is if they're
monkey-patching, which while a legitimate technique to achieve certain
ends when using other people's code-- is also not a technique which has
any place in consideration of the design phase of the original system
itself.

Certainly, importing a non-constant immutable piece of data is
problematic in theory, as it can be rebound and problems arise.

Number of times I've -seen- non-constant immutable data in the top-level
of a module: 0*.

-- 

   Stephen Hansen
   ... Also: Ixokai
   ... Mail: me+list/python (AT) ixokai (DOT) io
   ... Blog: http://meh.ixokai.io/

P.S. Outside of a throw-away script which is not meant to be imported,
at least.



signature.asc
Description: OpenPGP digital signature
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Re: Python OpenSSL library

[Antoine Pitrou]

On Tue, 15 Jun 2010 19:56:46 -0700
John Nagle  wrote:
> 
>  http://bugs.python.org/issue1589
[...]
> 
> The typical Python user will expect SSL checking for URL opening
> to behave like a browser does. They won't be up to speed on the
> internal mechanics of X.509 certificates.  The default case should
> be to require a hostname match (considering certificate wildcards,
> multiple common names, multiple alt names, etc.).
> 
> Expecting the caller to do this check is unreasonable.  It's
> about 70 lines of python code to cover all the cases.  And
> that's without proper support for error reporting for internationalized
> host names.

If you are interested in this, I would encourage you to post a patch or
a proposal on the aforementioned bug entry so as to add a hostname
checking function to the SSL module.
(m2crypto has its own implementation that can serve as a source of
inspiration, and test cases)

If/when that is done, the second step would be to integrate it by
default with the urllib module, and perhaps other ones.

Thanks

Antoine.


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Re: super() woes (n00b)

[J. Cliff Dyer]

On Thu, 2010-06-17 at 16:36 +, Deadly Dirk wrote:
> I cannot get right the super() function:
> Python 3.1.1+ (r311:74480, Nov  2 2009, 14:49:22) 
> [GCC 4.4.1] on linux2
> Type "copyright", "credits" or "license()" for more information.
>  No Subprocess 
> >>> class P:
> def __init__(__class__,self):
> print("I am a member of class P")
> 
> 
> >>> class C(P):
> def __init__(self):
> super().__init__(self)
> print("I am a member of class C")
> 
> 
> 
> class P:
> def __init__(self):
> print("I am a member of class P")
> 
> class C(P):
> def __init__(self):
> super().__init__(self)
> print("I am a member of class C")
> 
> x=C()
> 
> That is more or less the text from the "Quick Python Book". What am I 
> doing wrong?
> 

super gives you an instantiated version of the super class, which means
that you don't have to explicitly send self to any methods you call on
it.  

So use `super().__init__()` instead.
> -- 
> The missionaries go forth to Christianize the savages - 
> as if the savages weren't dangerous enough already.


-- 
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The inverse of .join

[Neil Cerutti]

What's the best way to do the inverse operation of the .join
function?

-- 
Neil Cerutti
-- 
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Re: The inverse of .join

[nn]

Neil Cerutti wrote:
> What's the best way to do the inverse operation of the .join
> function?
>
> --
> Neil Cerutti

split
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Re: super() woes (n00b)

[Matteo Landi]

I found few error in your code:
1 the constructor of P class seems to be wrong:

>>> class P(object):
...def __init__(self):
...print("I am a member of class P")
...

2 super() works with new style classes, i.e.  the ones which inherit
from 'object'

>>> class P:
...def __init__(__class__,self):
...print("I am a member of class P")
...

3 super() need a type as first argument, and an instance as second one:

>>> class C(P):
...def __init__(self):
...super().__init__(self)
...print("I am a member of class C")

Now it should work (not tested).

On Thu, Jun 17, 2010 at 6:53 PM, Deadly Dirk  wrote:
> On Thu, 17 Jun 2010 16:36:10 +, Deadly Dirk wrote:
>
>> I cannot get right the super() function: Python 3.1.1+ (r311:74480, Nov
>> 2 2009, 14:49:22) [GCC 4.4.1] on linux2
>> Type "copyright", "credits" or "license()" for more information.  No
>> Subprocess 
> class P:
>>     def __init__(__class__,self):
>>         print("I am a member of class P")
>>
>>
> class C(P):
>>     def __init__(self):
>>         super().__init__(self)
>>         print("I am a member of class C")
>>
>>
>>
>> class P:
>>     def __init__(self):
>>         print("I am a member of class P")
>>
>> class C(P):
>>     def __init__(self):
>>         super().__init__(self)
>>         print("I am a member of class C")
>>
>> x=C()
>>
>> That is more or less the text from the "Quick Python Book". What am I
>> doing wrong?
>
> I tried this, too:
>
 class C(P):
>    def __init__(self):
>        super(__class__).__init__(self)
>        print("I am a member of class C")
>
>
 x=C()
> Traceback (most recent call last):
>  File "", line 1, in 
>    x=C()
>  File "", line 3, in __init__
>    super(__class__).__init__(self)
> TypeError: must be type, not C

>
>
>
> --
> The missionaries go forth to Christianize the savages -
> as if the savages weren't dangerous enough already.
> --
> http://mail.python.org/mailman/listinfo/python-list
>



-- 
Matteo Landi
http://www.matteolandi.net/
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Re: The inverse of .join

[MRAB]

Neil Cerutti wrote:

What's the best way to do the inverse operation of the .join
function?


.split, possibly, although there will be problems if the string contains
other occurrences of the separator.
--
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Re: The inverse of .join

[Ian Kelly]

On Thu, Jun 17, 2010 at 11:45 AM, Neil Cerutti  wrote:
> What's the best way to do the inverse operation of the .join
> function?

Use the str.split method?
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Re: super() woes (n00b)

[Deadly Dirk]

On Thu, 17 Jun 2010 13:48:45 -0400, J. Cliff Dyer wrote:

> super gives you an instantiated version of the super class, which means
> that you don't have to explicitly send self to any methods you call on
> it.
> 
> So use `super().__init__()` instead.

Thanks. Interestingly enough, it works in Python 3, which is what the 
book is about. It doesn't work in Python 2.6

3.1:

Python 3.1.1+ (r311:74480, Nov  2 2009, 14:49:22) 
[GCC 4.4.1] on linux2
Type "copyright", "credits" or "license()" for more information.
 No Subprocess 
>>> class P:
def __init__(self):
print("I am a member of class P")

>>> class C(P):
def __init__(self):
super().__init__()
print("I am a member of class C")


>>> x=C()
I am a member of class P
I am a member of class C
>>> 

2.6:
Python 2.6.4 (r264:75706, Dec  7 2009, 18:45:15) 
[GCC 4.4.1] on linux2
Type "copyright", "credits" or "license()" for more information.


Personal firewall software may warn about the connection IDLE
makes to its subprocess using this computer's internal loopback
interface.  This connection is not visible on any external
interface and no data is sent to or received from the Internet.


IDLE 2.6.4   No Subprocess 
>>> class P:
def __init__(self):
print("I am a member of class P")

>>> class C(P):
def __init__(self):
super().__init__()
print("I am a member of class C")

>>> x=C()
Traceback (most recent call last):
  File "", line 1, in 
x=C()
  File "", line 3, in __init__
super().__init__()
TypeError: super() takes at least 1 argument (0 given)
>>> 


-- 
The missionaries go forth to Christianize the savages - 
as if the savages weren't dangerous enough already.
-- 
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Re: super() woes (n00b)

[Benjamin Kaplan]

On Thu, Jun 17, 2010 at 10:51 AM, Matteo Landi  wrote:
> I found few error in your code:
> 1 the constructor of P class seems to be wrong:
>
 class P(object):
> ...    def __init__(self):
> ...        print("I am a member of class P")
> ...
>
> 2 super() works with new style classes, i.e.  the ones which inherit
> from 'object'
>

The OP is using Python 3.1. All classes in Python 3.x are new style.
-- 
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Re: Python OpenSSL library

[geremy condra]

On Thu, Jun 17, 2010 at 10:49 AM, Antoine Pitrou  wrote:
> On Tue, 15 Jun 2010 19:56:46 -0700
> John Nagle  wrote:
>>
>>      http://bugs.python.org/issue1589
> [...]
>>
>> The typical Python user will expect SSL checking for URL opening
>> to behave like a browser does. They won't be up to speed on the
>> internal mechanics of X.509 certificates.  The default case should
>> be to require a hostname match (considering certificate wildcards,
>> multiple common names, multiple alt names, etc.).
>>
>> Expecting the caller to do this check is unreasonable.  It's
>> about 70 lines of python code to cover all the cases.  And
>> that's without proper support for error reporting for internationalized
>> host names.
>
> If you are interested in this, I would encourage you to post a patch or
> a proposal on the aforementioned bug entry so as to add a hostname
> checking function to the SSL module.
> (m2crypto has its own implementation that can serve as a source of
> inspiration, and test cases)
>
> If/when that is done, the second step would be to integrate it by
> default with the urllib module, and perhaps other ones.

John, I'll do this if you don't want to. Let me know.

Geremy Condra
-- 
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Re: super() woes (n00b)

[Ethan Furman]

Deadly Dirk wrote:

On Thu, 17 Jun 2010 13:48:45 -0400, J. Cliff Dyer wrote:


super gives you an instantiated version of the super class, which means
that you don't have to explicitly send self to any methods you call on
it.

So use `super().__init__()` instead.


Thanks. Interestingly enough, it works in Python 3, which is what the 
book is about. It doesn't work in Python 2.6


as Thomas Jollans said days ago:
> but you should really install Python 3.1 (it's in ubuntu, as others
> have said!) because you will almost certainly hit into other snags.

or, as Gabriele Lanaro said in that same thread:
> else take a book that covers python 2.x syntax

Cut-and-pasting-ly yours,

~Ethan~

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Import fails (newbie)

[mhorlick]

Hello,

I'm a newbie and I have a small problem. After invoking IDLE -->

Python 3.1.2 (r312:79149, Mar 21 2010, 00:41:52) [MSC v.1500 32 bit
(Intel)] on win32
Type "copyright", "credits" or "license()" for more information.
>>> import os,glob
>>> os.chdir('D:/Python_Programs')
>>> print(os.getcwd())
D:\Python_Programs
>>> print(glob.glob('*.*'))
['humansize.py', 'humansize.pyc']
>>> import humansize
Traceback (most recent call last):
  File "", line 1, in 
import humansize
ImportError: No module named humansize
>>>

In a DOS command window I have no problems with the program:

 Directory of D:\Python_Programs

17/06/2010  01:56 PM  .
17/06/2010  01:56 PM  ..
17/06/2010  02:53 PM 1,266 humansize.py
17/06/2010  01:56 PM 1,315 humansize.pyc
   2 File(s)  2,581 bytes
   2 Dir(s)  104,122,085,376 bytes free

D:\Python_Programs>c:\python31\python humansize.py
1.0 TB
931.3 GiB

This 'humansize.py' program I got from the book 'Dive Into Python 3'.
I don't know if you need to know the source.

Can someone explain why the 'import' fails?

Thanks,

Mike
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Re: The inverse of .join

[Neil Cerutti]

On 2010-06-17, Ian Kelly  wrote:
> On Thu, Jun 17, 2010 at 11:45 AM, Neil Cerutti
>  wrote:
>> What's the best way to do the inverse operation of the .join
>> function?
>
> Use the str.split method?

split is perfect except for what happens with an empty string.

-- 
Neil Cerutti
-- 
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Processing HTML form

[Bradley Hintze]

Hi,

I am a newbie to anything web related, I know a bit  of HTML though.
I've been programing in python for a year or so so I know the language
at an intermediate level. I am wondering if its possible to get info
from an HTML form and pass it to my python code and return a page
based on  the code executed. All of my web searches have been
fruitless as I quickly get lost in the jargon and perhaps not sure
what phrase i should search. Any help would be appreciated.

Thank you,
Bradley
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Running a program from another program.

[Laurent Verweijen]

I have a program called increment.py as follows: 

#!/usr/bin/python
n = 0
while True:
n = int(raw_input(n)) + 1

This is probably very easy to understand, but I want to run this program
from another python program.
Below is an attempt

>>> from subprocess import *
>>> p = Popen(["python", "increment.py"], stdin=PIPE,
stdout=PIPE)
>>> p.communicate("5")
Traceback (most recent call last):
  File "increment.py", line 4, in 
n = int(raw_input(n)) + 1
EOFError: EOF when reading a line
('06', None)
>>> p.communicate("7")
Traceback (most recent call last):
  File "", line 1, in 
  File "/usr/lib/python2.6/subprocess.py", line 701, in
communicate
return self._communicate(input)
  File "/usr/lib/python2.6/subprocess.py", line 1184, in
_communicate
self.stdin.flush()
ValueError: I/O operation on closed file

How do I make sure the inputstream stays open after the first call to
communicate?


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Black-Jewish History FAQ - Is The Secret Relationshi p between blacks and jews a “hate literature”?

[nanothermite911fbibustards]

http://www.blacksandjews.com/JewsBlackHolocaust.html

Blacks and Jews have been involved in a re-evaluation of their current
and historical relationship. Events of the past several years have
raised both tensions and the level of rhetoric coming from all sides.
The Secret Relationship Between Blacks and Jews is a historical
accounting of the part of the relationship that has been ignored by
both Blacks and Jews.

http://www.blacksandjews.com/BlackJewishFAQ.html

http://www.blacksandjews.com/BlackJewishFAQ.Hate.html

Black-Jewish History FAQ - Is The Secret Relationship between blacks
and jews a “hate literature”?


No. It is truth literature. The release in 1991 of The Secret
Relationship Between Blacks and Jews, Vol. 1, offered the world a
glimpse of how the so-called chosen people have historically related
to the Blacks with whom they have come into contact. Jews, upset with
the revelation, have reacted by condemning the book as “unscholarly”
and “hate literature.” But at the same time many, many academic
libraries have quietly bought the book and put it in their
collections. At least 115 libraries around the world now have the book
in their collections, including such prestigious institutions as Yale,
Harvard, Princeton, Brandeis, Yeshiva University, the Jewish
Theological Seminary, Brown University, Stanford University, even
Cambridge University in London, England, and others in Germany and New
Zealand, all of which have the book on their library shelves.

Some libraries have the book but keep it locked away in a special
location, requiring ID in order to see it. At one point the Brandeis
University library kept it, along with other important works, in what
they called “The Cage.” The Library of Congress wrote to the NOI and
demanded a copy (which was supplied).

There have been more than a dozen books and dozens more articles
written to try to refute The Secret Relationship Between Blacks and
Jews, Vol. 1. One scholar called this new body of scholarship spawned
by The Secret Relationship a “cottage industry.” The Jewish leaders
have held high-level meetings at retailers like Barnes & Noble and
Borders about what to do with this bestseller. One store in California
was putting one of these “refutation” books in the bags of any Black
customer who bought any book on any topic. Canada was stopping The
Secret Relationship at the border and labeling it “contraband.” On the
official form the border agents could check one of three categories:
“pornography,” “hate literature,” or “other.” They checked “other.”

Libraries list the book as “history”—not “hate literature”— and have
deemed it too important to the discourse on the Black–Jewish
relationship to exclude it.

Other Libraries that own Volume 1 include:
FOREIGN
London Library of Haringay, UK
London Library of Newham, UK
Yorkshire Library, UK
Senckenberg Univ., Frankfurt, Germany
Univ. of Otago Library, New Zealand
Vancouver Public Library
Univ. of the W. Indies, Barbados
British Library
University of Toronto Libraries
UNITED STATES
New York University
Smith College
Amherst College
College of the Holy Cross
Northeastern University
UCLA Library
University of California, Davis
University of California, Irvine
University of San Diego
University of Southern California
University of California Berkeley
Hoover Institute, Stanford, CA
University of Texas, Austin
Texas A&M University, Kingsville
Maricopa Community Colleges
Whitman College, Walla Walla, WA
Multnomah County Library
Pierce College Library
University of Nevada, Reno
Rice University, Fondren Library
Wisconsin Historical Society
Atlanta-Fulton Public Library
Doane College
California State, Northridge
Florida Atlantic University
Missouri State University
Grambling State University
Pittsburg State University
Southern University in New Orleans
Sam Houston State University
University of Miami
University of West Georgia
University of Iowa Library
University of Florida
Saint Louis Public Library
Southeast Missouri State University
Mervyn H. Sterne Library
Grinnell College
University of Chicago
Chicago Public Library

Loyola University Libraries
Saint Xavier University Library
Milwaukee Library System
Western Kentucky University
University of Illinois
Savannah State University
Fayetteville State University
Michigan State University Libraries
Antioch College
Barber-Scotia College
Davidson College Library
Allen County Public Library
Calvin College & Theological Seminary
Indiana State University
University of Akron
Detroit Public Library
Duke University Library
North Carolina State University
Univ. of North Carolina, Chapel Hill
Ohio State University
Toledo-Lucas County Public Library
Eastern Michigan University Library
University of Michigan Library
Bowling Green State University
Bucknell University
Concordia Univ. Library
McGill University
Delaware State University
University of Maryland, College Park
University of Pittsburgh
Hampton University
Elizabeth City State University
Bowdoin College
Temple University L

* Black-Jewish History FAQ - Is The Secret Relations hip between blacks and jews a “hate literature”? *

[nanothermite911fbibustards]

http://www.blacksandjews.com/JewsBlackHolocaust.html

Jews and the Black Holocaust - What are the Issues?

Blacks and Jews have been involved in a re-evaluation of their current
and historical relationship. Events of the past several years have
raised both tensions and the level of rhetoric coming from all sides.
The Secret Relationship Between Blacks and Jews is a historical
accounting of the part of the relationship that has been ignored by
both Blacks and Jews. Most people are not even aware of the extensive
record of encounters between the two groups prior to the 20th century.
The Honorable Louis Farrakhan referred to this well-documented history
in 1984 and was immediately labeled an "anti-Semite." Merely
questioning the belief that Jews were co-sufferers in the Black slave
experience draws angry rebukes from Jews of all stripes. The book in
question presents indisputable historical data from census records,
wills, Jewish historians and scholars, rabbinical sermons, port
records, court records, runaway slave notices, slave sale
advertisements, etc., which forces all sides to grapple with the long-
held mythology that Black people always found a friend in the Jews.

Some Jews and their dutiful negros have hired the services of Dr.
Harold Brackman of the Simon Wiesenthal Center in an effort to
preserve the comfortable mythology which has obscured the actual
historical record. But unbeknownst to them, Dr. Brackman's 1977
unpublished Ph.D. dissertation, entitled The Ebb and Flow of Conflict,
goes far beyond The Secret Relationship in its claims of Jewish
conspiracy in the Biblical origin of White supremacy. He clearly
states that Jewish Talmudic scholars invented the Hamitic Myth which,
through the story of Noah, everlastingly assigned to the African the
role of slave and divinely cursed servant of White people. According
to Dr. Tony Martin's book, The Jewish Onslaught, the Jewish invention
of the Hamitic Myth "provided the moral pretext upon which the entire
trade grew and flourished."

"There is no denying," said Brackman of the story of Noah, "that the
Babylonian Talmud was the first source to read a Negrophobic content
into the episode..." Brackman pointed out further that two third
century Jewish "Sages" provided homosexual embellishments for the
Biblical story as well.

This "curse" was the absolute basis for the Europeans' choice of dark-
skinned Africans for chattel slavery. Many denominations of
Christianity, Islam and Judaism believe it and teach it to this very
moment! Southern plantation owners attacked the Abolitionists with it;
its teaching was the foundation of the slaves' permitted religion;
Black inferiority is based on it; the Ku Klux Klan relies on it; even
the Mormons officially taught it until 1978. When the Jews invented it
and promoted it to the world they sentenced the Black Race to a
holocaust the likes of which no people have ever suffered. "Hate
teaching" will forever be defined by this wicked belief system brought
to us in the Jewish Holy Talmud via Harold Brackman.

The critics curiously use a Harvard English teacher, Henry Louis
Gates, to offer historical clarity. Gates exhibits no evidence that he
even read the book in his oft-quoted NY Times opinion. His willingness
to make asinine historical claims with the glaring absence of support
from reputable Black or Jewish historians proves Adam Clayton Powell's
axiom: "Harvard has ruined more negroes than bad whiskey."

Overwhelming Evidence

The history that the old "Black-Jewish Coalition" clumsily avoids is
the entire three century history of Jewish presence in South America
and the Caribbean. But other highly acclaimed Jewish scholars have not
been so blind:


•Lee M. Friedman, a one-time president of the American Jewish
Historical Society, wrote that in Brazil, where most of the Africans
actually went, "the bulk of the slave trade was in the hands of Jewish
settlers."


•Marcus Arkin wrote that the Jews of Surinam used "many thousands" of
Black slaves.


•Herbert I. Bloom wrote that "the slave trade was one of the most
important Jewish activities here (in Surinam) as elsewhere in the
colonies." He even published a 1707 list of Jewish buyers by name with
the number of Black humans they purchased.


•Cecil Roth, writer of 30 books and hundreds of articles on Jewish
history, wrote that the slave revolts in parts of South America "were
largely directed against [Jews] as being the greatest slave-holders of
the region."


•"I gather," wrote Jewish scholar Wilfred Samuels, "that the Jews [of
Barbados] made a good deal of their money by purchasing and hiring out
negroes..."


•According to the Jewish historians, all Barbadian Jews owned slaves -
even the rabbi had "the enjoyment of his own two negro attendants."


•In Curaçao which was a major slave trading depot, Isaac and Susan
Emmanuel report that "the shipping business was mainly a Jewish
enterprise."


•Says yet another Jewish writer of the Jews of Curaçao, "Almost every
Jew bou

Re: The inverse of .join

[MRAB]

Neil Cerutti wrote:

On 2010-06-17, Ian Kelly  wrote:

On Thu, Jun 17, 2010 at 11:45 AM, Neil Cerutti
 wrote:

What's the best way to do the inverse operation of the .join
function?

Use the str.split method?


split is perfect except for what happens with an empty string.


I see what you mean.

This is consistent:

>>> ','.join([''])
''
>>> ''.split(',')
['']

but this isn't:

>>> ','.join([])
''
>>> ''.split(',')
['']

An empty string could be the result of .join(['']) or .join([]).

Should .split grow an addition keyword argument to specify the desired
behaviour? (Although it's simple enough to define your own function.)
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Re: Processing HTML form

[Grant Edwards]

On 2010-06-17, Bradley Hintze  wrote:

> I am a newbie to anything web related, I know a bit  of HTML though.
> I've been programing in python for a year or so so I know the language
> at an intermediate level. I am wondering if its possible to get info
> from an HTML form and pass it to my python code and return a page
> based on  the code executed. All of my web searches have been
> fruitless as I quickly get lost in the jargon and perhaps not sure
> what phrase i should search. Any help would be appreciated.

It's not clear what you want.  Are you talking about Python code in an
HTTP client or an HTTP server?

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Re: The inverse of .join

[Robert Kern]

On 6/17/10 2:08 PM, Neil Cerutti wrote:

On 2010-06-17, Ian Kelly  wrote:

On Thu, Jun 17, 2010 at 11:45 AM, Neil Cerutti
  wrote:

What's the best way to do the inverse operation of the .join
function?


Use the str.split method?


split is perfect except for what happens with an empty string.


Why don't you try it and find out?

--
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
 that is made terrible by our own mad attempt to interpret it as though it had
 an underlying truth."
  -- Umberto Eco

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Re: The inverse of .join

[Stephen Hansen]

On 6/17/10 12:44 PM, MRAB wrote:
> Neil Cerutti wrote:
>> On 2010-06-17, Ian Kelly  wrote:
>>> On Thu, Jun 17, 2010 at 11:45 AM, Neil Cerutti
>>>  wrote:
 What's the best way to do the inverse operation of the .join
 function?
>>> Use the str.split method?
>>
>> split is perfect except for what happens with an empty string.
>>
> I see what you mean.
> 
> This is consistent:
> 
 ','.join([''])
> ''
 ''.split(',')
> ['']
> 
> but this isn't:
> 
 ','.join([])
> ''
 ''.split(',')
> ['']
> 
> An empty string could be the result of .join(['']) or .join([]).
> 
> Should .split grow an addition keyword argument to specify the desired
> behaviour? (Although it's simple enough to define your own function.)

Guido finds keyword-arguments-to-change-behavior to be unPythonic, IIRC.
It generally means 'make a new API'. But, the question is-- is it worth
the mental strain of a new API?

This is such an extreme edge case, having to do:

  if blah:
result = blah.split(',')
  else:
result = []

Is really not asking too much, I think.

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Re: Running a program from another program.

[Stephen Hansen]

On 6/17/10 12:13 PM, Laurent Verweijen wrote:
> How do I make sure the inputstream stays open after the first call to
> communicate?

This was just asked a few days ago in different words-- check out the
thread, a couple solutions are offered. In short, you need to make
stdin/stdout non-blocking:

http://groups.google.com/group/comp.lang.python/browse_thread/thread/066de1c0fd38642f#

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Possible to reach back in stack and grab calling function's locals()?

[python]

Is there an elegant way to reach back in the stack and grab the
calling function's copy of locals()?

I'm working on a library that does lots of textmerge operations
and am looking for a way to eliminate the need for many of the
calls to our library to have to explictly pass locals() to our
formatting functions.

Thank you,
Malcolm
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Re: The inverse of .join

[Neil Cerutti]

On 2010-06-17, Robert Kern  wrote:
> On 6/17/10 2:08 PM, Neil Cerutti wrote:
>> On 2010-06-17, Ian Kelly  wrote:
>>> On Thu, Jun 17, 2010 at 11:45 AM, Neil Cerutti
>>>   wrote:
 What's the best way to do the inverse operation of the .join
 function?
>>>
>>> Use the str.split method?
>>
>> split is perfect except for what happens with an empty string.
>
> Why don't you try it and find out?

I'm currently using the following without problems, while reading
a data file. One of the fields is a comma separated list, and may
be empty.

  f = rec['codes']
  if f == "":
f = []
  else:
f = f.split(",")

I just wondered if something smoother was available.

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Re: how to get bit info

[Laurent Verweijen]

Op donderdag 17-06-2010 om 12:51 uur [tijdzone -0700], schreef Back9: 
> Hi,
> 
> I have one byte data and want to know each bit info,
> I mean how I can know each bit is set or not?
> 
> TIA

def bitset(x, n):
"""Return whether nth bit of x was set"""
return bool(x & (1 << n))

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Re: Serializing functions

[Aaron Staley]

I am one of the developer's of PiCloud.

To answer your question, we wrote a custom subclass of Pickler to
pickle functions.  As Robert pointed out, the library is LGPL, so you
can see (and use) the source code.  I also presented the details on a
poster at PyCon 2010.  You can see it here:
http://blog.picloud.com/?p=96


On Jun 17, 9:26 am, Robert Kern  wrote:
> On 6/17/10 8:23 AM, Matteo Landi wrote:
>
>
>
>
>
> > Some weeks ago, here on the mailing list I read about picloud[1], a
> > python library used for cloud-computing; I was impressed by its
> > simplicity, here is an example:
>
>  import cloud
>  def square(x):
> > ...  return x * x
>  cloud.call(square, 10)
>  cloud.result()
> > 100
>
> > So, I tried to figure out how to achieve the same result, i.e. define a
> > local generic function and send it somewhere for remote execution, and
> > the get the result back.
> > So I thought about serialization (pickle): I made a few tries and it
> > seemed to work.. but I was wrong, because I never tried to load pickled
> > data from another session different from the one used to pickle data
> > itself. If you try and pickle a function, it is not pickled as a whole,
> > indeed, once you unpickle it, it will raise an exception telling you
> > that the target function was not found in the current module.
>
> > So I'm here, with nothing in my hands; how would you implement this?
>
> PiCloud's client library is LGPLed. Go take a look for yourself. It's pretty 
> nifty.
>
> [Disclosure: My employer, Enthought, has partnered with PiCloud to provide our
> Enthought Python Distribution to PiCloud users. However, I say that it's nifty
> purely because it is.]
>
> --
> Robert Kern
>
> "I have come to believe that the whole world is an enigma, a harmless enigma
>   that is made terrible by our own mad attempt to interpret it as though it 
> had
>   an underlying truth."
>    -- Umberto Eco

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Re: how to get bit info

[Tim Lesher]

On Jun 17, 3:51 pm, Back9  wrote:
> Hi,
>
> I have one byte data and want to know each bit info,
> I mean how I can know each bit is set or not?

You want the bitwise-and operator, &.

For example, to check the least significant bit, bitwise-and with 1:

>>> 3 & 1
1
>>> 2 & 1
0
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Re: how to get bit info

[Stephen Hansen]

On 6/17/10 12:51 PM, Back9 wrote:
> I have one byte data and want to know each bit info,
> I mean how I can know each bit is set or not?

>>> BIT_1 = 1 << 0
>>> BIT_2 = 1 << 1
>>> BIT_3 = 1 << 2
>>> BIT_4 = 1 << 3
>>> BIT_5 = 1 << 4
>>> BIT_6 = 1 << 5
>>> BIT_7 = 1 << 6
>>> BIT_8 = 1 << 7
>>> byte = 67
>>> if byte & BIT_1:
... print "Bit 1 is set!"
... else:
... print "Bit 1 is not set!"
Bit 1 is set!
>>> if not byte & BIT_6:
... byte = byte | BIT_6
... print "Bit 6 wasn't set, BUT NOW IS."
Bit 6 wasn't set, BUT NOW IS.
>>> byte
99

(I added 'how to set a specific bit' just cuz)

Basically, those BIT_X lines are creating numbers which have *only* the
specified bit set. Then you do "byte & BIT_X", and that will return 0 if
the byte doesn't have the specified bit in it. You can then set the bit
with "byte | BIT_X", and unset the bit with "byte ^ BIT_X".

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Re: how to get bit info

[Irmen de Jong]

On 17-6-2010 21:51, Back9 wrote:

Hi,

I have one byte data and want to know each bit info,
I mean how I can know each bit is set or not?

TIA


Use bitwise and, for instance, to see if the third bit is set:

byte = 0b
if byte & 0b0100:
print "bit is set"

-irmen
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Re: Processing HTML form

[Bradley Hintze]

I apologize in advance for my lack of knowledge, I really do not know.
I would guess server but I quite honestly I am not clear what an 'HTTP
client' or 'HTTP server' refers to. I am running a webpage and am
serving it locally for the moment. I have a program that is already
written in Python. I want to make the program available on the web
where I receive user input from HTML forms. The user input will then
be used as parameters for the program. I hope this clear things up.

Thanks,
Bradley

On Thu, Jun 17, 2010 at 3:46 PM, Grant Edwards  wrote:
> On 2010-06-17, Bradley Hintze  wrote:
>
>> I am a newbie to anything web related, I know a bit  of HTML though.
>> I've been programing in python for a year or so so I know the language
>> at an intermediate level. I am wondering if its possible to get info
>> from an HTML form and pass it to my python code and return a page
>> based on  the code executed. All of my web searches have been
>> fruitless as I quickly get lost in the jargon and perhaps not sure
>> what phrase i should search. Any help would be appreciated.
>
> It's not clear what you want.  Are you talking about Python code in an
> HTTP client or an HTTP server?
>
> --
> Grant Edwards               grant.b.edwards        Yow! ... I have read the
>                                  at               INSTRUCTIONS ...
>                              gmail.com
> --
> http://mail.python.org/mailman/listinfo/python-list
>



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Re: Processing HTML form

[Marco Nawijn]

On 17 jun, 21:11, Bradley Hintze  wrote:
> Hi,
>
> I am a newbie to anything web related, I know a bit  of HTML though.
> I've been programing in python for a year or so so I know the language
> at an intermediate level. I am wondering if its possible to get info
> from an HTML form and pass it to my python code and return a page
> based on  the code executed. All of my web searches have been
> fruitless as I quickly get lost in the jargon and perhaps not sure
> what phrase i should search. Any help would be appreciated.
>
> Thank you,
> Bradley

Hi Bradley,

If I understand correctly, you want to do the following:
   1. Fill in a HTML form in a client (web browser)
   2. Send the form to a webserver
   3. Have the webserver extract the information from the form
   4. Send the information to a python program for processing
   5. Generate a new HTML page in python based on the information in
step 4
   6. Send the newly generated page back to the client

Possible solutions depend a little on the constraints and/or options
you have for the webserver. If you are free in your choices I would
suggest to start with cherrypy (www.cherrypy.org) for a webserver. It
is simple to start with, very powerfull and well documented. This
would cover steps 3 and 4. For step 5 I suggest you either use the
python builtin string template facility string.Template (for simple
things). If you want more power have a look at Genshi 
http://genshi.edgewall.org.

The two options I mention above help you to understand whats going on.
If you feel comfortable with this, you can take a look at python web
frameworks like Django or Turbogears (or many others).

Good luck and keep us posted with what your progress.

Regards,

Marco
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Re: List of lists surprising behaviour

[J Kenneth King]

candide  writes:

> Let's the following code :
>
 t=[[0]*2]*3
 t
> [[0, 0], [0, 0], [0, 0]]
 t[0][0]=1
 t
> [[1, 0], [1, 0], [1, 0]]
>
> Rather surprising, isn't it ? 

Not at all, actually.

I'd be surprised if the multiplication operator was aware of object
constructors.  Even arrays are "objects" in Python.  Should the
multiplication operator know how to instantiate three arrays from a
single array instance?  What about an instance of a user-defined class?

> So I suppose all the subarrays reférence
> the same array :
>
 id(t[0]), id(t[1]), id(t[2])
> (3077445996L, 3077445996L, 3077445996L)

>

As they should.

>
> So what is the right way to initialize to 0 a 2D array ? Is that way
> correct  :
>
>
 t=[[0 for _ in range(2)] for _ in range(3)]
>
> It seems there is no more trouble now :
>
 t
> [[0, 0], [0, 0], [0, 0]]
 t[0][0]=1
 t
> [[1, 0], [0, 0], [0, 0]]

>
> Correct ?

>>> 2d_zero_vector = lambda len: [[0, 0] for _ in range(len)]
>>> t = 2d_zero_vector(3)
>>> print t
[[0, 0], [0, 0], [0, 0]]
>>> t[0][0] = 1
>>> print t
[[1, 0], [0, 0], [0, 0], [0, 0]]

(Of course, if you're doing matrix math you'll probably want to work
with numpy which has a function for doing just this)
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Re: how to get bit info

[Grant Edwards]

On 2010-06-17, Stephen Hansen  wrote:

 BIT_1 = 1 << 0
 BIT_2 = 1 << 1

...

> Basically, those BIT_X lines are creating numbers which have *only* the
> specified bit set. Then you do "byte & BIT_X", and that will return 0 if
> the byte doesn't have the specified bit in it. You can then set the bit
> with "byte | BIT_X", and unset the bit with "byte ^ BIT_X".

Just to clarify, "byte ^ BIT_X" inverts (toggles) bit X.

If you want to make sure bit X is a 0 (which is what people usually
mean by "unset"), you do "byte & ~BIT_X"

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Python distributing localization files

[Gabriele Lanaro]

Hi, I want to localize my application (a pygtk gui app), what's the best way
to distribute and install localization files?
I'm currently using `distribute` to package it.

Any suggestion?
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Re: Processing HTML form

[Grant Edwards]

On 2010-06-17, Bradley Hintze  wrote:

> I apologize in advance for my lack of knowledge, I really do not know.
> I would guess server but I quite honestly I am not clear what an 'HTTP
> client' or 'HTTP server' refers to. I am running a webpage and am
> serving it locally for the moment. I have a program that is already
> written in Python. I want to make the program available on the web
> where I receive user input from HTML forms. The user input will then
> be used as parameters for the program. I hope this clear things up.

Something that serves a web page is an HTTP server, so it sounds like
your program is going to be run by/in the HTTP server.  There are
many, many different ways to do that.  For starters you need to tell
us what OS you're using and what HTTP server you're using.

Or do you want your program to _be_ an HTTP server?

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Re: The inverse of .join

[Robert Kern]

On 6/17/10 3:03 PM, Neil Cerutti wrote:

On 2010-06-17, Robert Kern  wrote:

On 6/17/10 2:08 PM, Neil Cerutti wrote:

On 2010-06-17, Ian Kelly   wrote:

On Thu, Jun 17, 2010 at 11:45 AM, Neil Cerutti
   wrote:

What's the best way to do the inverse operation of the .join
function?


Use the str.split method?


split is perfect except for what happens with an empty string.


Why don't you try it and find out?


I would like to apologize. I read that sentence as a question for some reason.

That said, it always helps for you to show the results that you are getting (and 
the code that gives those results) and state what results you were expecting.


--
Robert Kern

"I have come to believe that the whole world is an enigma, a harmless enigma
 that is made terrible by our own mad attempt to interpret it as though it had
 an underlying truth."
  -- Umberto Eco

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Re: Running a program from another program.

[Laurent Verweijen]

Op donderdag 17-06-2010 om 13:01 uur [tijdzone -0700], schreef Stephen
Hansen: 
> On 6/17/10 12:13 PM, Laurent Verweijen wrote:
> > How do I make sure the inputstream stays open after the first call to
> > communicate?
> 
> This was just asked a few days ago in different words-- check out the
> thread, a couple solutions are offered. In short, you need to make
> stdin/stdout non-blocking:
> 
> http://groups.google.com/group/comp.lang.python/browse_thread/thread/066de1c0fd38642f#
> 

I tried putting what Ian Kelly said in my code, by it doesn't work for
me.

Python 2.6.5 (r265:79063, Apr 16 2010, 13:57:41) 
[GCC 4.4.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> import os
>>> import fcntl
>>> import subprocess
>>> process = subprocess.Popen(["python", "increment.py"], stdin =
subprocess.PIPE, stdout = subprocess.PIPE)
>>> flags = fcntl.fcntl(process.stdout, fcntl.F_GETFL)
>>> fcntl.fcntl(process.stdout, fcntl.F_SETFL, flags | os.O_NONBLOCK)
0
>>> process.stdin.write("5\n")
>>> process.stdout.read()
Traceback (most recent call last):
  File "", line 1, in 
IOError: [Errno 11] Resource temporarily unavailable

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Re: Running a program from another program.

[Stephen Hansen]

On 6/17/10 1:42 PM, Laurent Verweijen wrote:
> I tried putting what Ian Kelly said in my code, by it doesn't work for
> me.
> 
> Python 2.6.5 (r265:79063, Apr 16 2010, 13:57:41) 
> [GCC 4.4.3] on linux2
> Type "help", "copyright", "credits" or "license" for more information.
 import os
 import fcntl
 import subprocess
 process = subprocess.Popen(["python", "increment.py"], stdin =
> subprocess.PIPE, stdout = subprocess.PIPE)
 flags = fcntl.fcntl(process.stdout, fcntl.F_GETFL)
 fcntl.fcntl(process.stdout, fcntl.F_SETFL, flags | os.O_NONBLOCK)
> 0
 process.stdin.write("5\n")
 process.stdout.read()
> Traceback (most recent call last):
>   File "", line 1, in 
> IOError: [Errno 11] Resource temporarily unavailable

I *believe* that error in response to "read()" is something you should
catch: its EAGAIN. Meaning, for it to perform that operation, it would
have to block, but you've set it to not block.

Thus, your subprocess hasn't written anything new out yet by the time
you call that. You have to try/except looking for that and catch it.

That's why I preferred the recipe I linked to in that thread: it uses
select to only read when there's something -to- actually read.

-- 

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Re: Running a program from another program.

[Laurent Verweijen]

Op donderdag 17-06-2010 om 13:48 uur [tijdzone -0700], schreef Stephen
Hansen: 
> On 6/17/10 1:42 PM, Laurent Verweijen wrote:
> > I tried putting what Ian Kelly said in my code, by it doesn't work for
> > me.
> > 
> > Python 2.6.5 (r265:79063, Apr 16 2010, 13:57:41) 
> > [GCC 4.4.3] on linux2
> > Type "help", "copyright", "credits" or "license" for more information.
>  import os
>  import fcntl
>  import subprocess
>  process = subprocess.Popen(["python", "increment.py"], stdin =
> > subprocess.PIPE, stdout = subprocess.PIPE)
>  flags = fcntl.fcntl(process.stdout, fcntl.F_GETFL)
>  fcntl.fcntl(process.stdout, fcntl.F_SETFL, flags | os.O_NONBLOCK)
> > 0
>  process.stdin.write("5\n")
>  process.stdout.read()
> > Traceback (most recent call last):
> >   File "", line 1, in 
> > IOError: [Errno 11] Resource temporarily unavailable
> 
> I *believe* that error in response to "read()" is something you should
> catch: its EAGAIN. Meaning, for it to perform that operation, it would
> have to block, but you've set it to not block.
> 
> Thus, your subprocess hasn't written anything new out yet by the time
> you call that. You have to try/except looking for that and catch it.
> 
> That's why I preferred the recipe I linked to in that thread: it uses
> select to only read when there's something -to- actually read.
> 

It just gives me an empty string.

Python 2.6.5 (r265:79063, Apr 16 2010, 13:57:41) 
[GCC 4.4.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> from asynchronous import *
>>> p = Popen(["python", "increment.py"], stdin=PIPE, stdout=PIPE)
>>> send_all(p, "5\n")
>>> recv_some(p)
''
>>> send_all(p, "6\n")
>>> recv_some(p)
''


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Re: Processing HTML form

[Bradley Hintze]

I am on Mac OSX 10.6, server is apache. If I do get this working we
will move it to the main server which also serves apache, i believe.I
dont think I want a whole new server, I'd like to serve from the
apache framework if possible.

On Thu, Jun 17, 2010 at 4:34 PM, Grant Edwards  wrote:
> On 2010-06-17, Bradley Hintze  wrote:
>
>> I apologize in advance for my lack of knowledge, I really do not know.
>> I would guess server but I quite honestly I am not clear what an 'HTTP
>> client' or 'HTTP server' refers to. I am running a webpage and am
>> serving it locally for the moment. I have a program that is already
>> written in Python. I want to make the program available on the web
>> where I receive user input from HTML forms. The user input will then
>> be used as parameters for the program. I hope this clear things up.
>
> Something that serves a web page is an HTTP server, so it sounds like
> your program is going to be run by/in the HTTP server.  There are
> many, many different ways to do that.  For starters you need to tell
> us what OS you're using and what HTTP server you're using.
>
> Or do you want your program to _be_ an HTTP server?
>
> --
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>                                  at               HITCHHIKING to CINCINNATI
>                              gmail.com            or FAR ROCKAWAY!!
> --
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>



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Re: Processing HTML form

[Benjamin Kaplan]

On Thu, Jun 17, 2010 at 1:15 PM, Bradley Hintze
 wrote:
> I apologize in advance for my lack of knowledge, I really do not know.
> I would guess server but I quite honestly I am not clear what an 'HTTP
> client' or 'HTTP server' refers to. I am running a webpage and am
> serving it locally for the moment. I have a program that is already
> written in Python. I want to make the program available on the web
> where I receive user input from HTML forms. The user input will then
> be used as parameters for the program. I hope this clear things up.
>
> Thanks,
> Bradley
>

HTTP Client = web browser.
HTTP Server = the server,

You'll probably want to use a framework like Django to help you with
this- this is exactly what they were designed to do. What the
frameworks do is let you map URLs to functions. Your form data will
get sent to the server in a POST request, and the framework will hand
that to your function as arguments. Then, your function will generate
the web page (often using a template where you just fill in the
blanks) and send that back to the browser.
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Re: Py_single_input and the side-effects...

[Mark Lawrence]

On 05/06/2010 11:11, Gabriel Genellina wrote:

On 31 mayo, 08:11, moerchendiser2k3  wrote:


you are right, Python still holds the last
reference. I just set a dummy and thats it :)

Can you tell me where did you get the information from?


Do you mean the _ variable?
It's in the tutorial:
http://docs.python.org/tutorial/introduction.html#using-python-as-a-calculator

--
Gabriel Genellina


I have always believed that the _ variable is only available 
interactively because of this comment in the tutorial:-
"In interactive mode, the last printed expression is assigned to the 
variable _. This means that when you are using Python as a desk 
calculator, it is somewhat easier to continue calculations, for example: 
..."


However a thread from IIRC a couple of days back used _ to say "I'm not 
interested in you, I'm throwing you away" in a list comprehension or 
whatever.  I've tried this in a script this evening and it works perfectly.


print 'total', sum(amount for _, amount in outputs)

Where is the use of _ in a script documented, I've searched all over and 
can't find it, guess I don't have the Midas touch with google? :)


Kindest regards.

Mark Lawrence.

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Re: Running a program from another program.

[Stephen Hansen]

On 6/17/10 2:09 PM, Laurent Verweijen wrote:
> It just gives me an empty string.
> 
> Python 2.6.5 (r265:79063, Apr 16 2010, 13:57:41) 
> [GCC 4.4.3] on linux2
> Type "help", "copyright", "credits" or "license" for more information.
 from asynchronous import *
 p = Popen(["python", "increment.py"], stdin=PIPE, stdout=PIPE)
 send_all(p, "5\n")
 recv_some(p)
> ''
 send_all(p, "6\n")
 recv_some(p)
> ''

Yes, that's how it signals the same situation. The point is: your
subprocess isn't outputting anything. You sure its not crashing out, for
instance?

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Re: Running a program from another program.

[Laurent Verweijen]

Op donderdag 17-06-2010 om 23:09 uur [tijdzone +0200], schreef Laurent
Verweijen: 
> Op donderdag 17-06-2010 om 13:48 uur [tijdzone -0700], schreef Stephen
> Hansen: 
> > On 6/17/10 1:42 PM, Laurent Verweijen wrote:
> > > I tried putting what Ian Kelly said in my code, by it doesn't work for
> > > me.
> > > 
> > > Python 2.6.5 (r265:79063, Apr 16 2010, 13:57:41) 
> > > [GCC 4.4.3] on linux2
> > > Type "help", "copyright", "credits" or "license" for more information.
> >  import os
> >  import fcntl
> >  import subprocess
> >  process = subprocess.Popen(["python", "increment.py"], stdin =
> > > subprocess.PIPE, stdout = subprocess.PIPE)
> >  flags = fcntl.fcntl(process.stdout, fcntl.F_GETFL)
> >  fcntl.fcntl(process.stdout, fcntl.F_SETFL, flags | os.O_NONBLOCK)
> > > 0
> >  process.stdin.write("5\n")
> >  process.stdout.read()
> > > Traceback (most recent call last):
> > >   File "", line 1, in 
> > > IOError: [Errno 11] Resource temporarily unavailable
> > 
> > I *believe* that error in response to "read()" is something you should
> > catch: its EAGAIN. Meaning, for it to perform that operation, it would
> > have to block, but you've set it to not block.
> > 
> > Thus, your subprocess hasn't written anything new out yet by the time
> > you call that. You have to try/except looking for that and catch it.
> > 
> > That's why I preferred the recipe I linked to in that thread: it uses
> > select to only read when there's something -to- actually read.
> > 
> 
> It just gives me an empty string.
> 
> Python 2.6.5 (r265:79063, Apr 16 2010, 13:57:41) 
> [GCC 4.4.3] on linux2
> Type "help", "copyright", "credits" or "license" for more information.
> >>> from asynchronous import *
> >>> p = Popen(["python", "increment.py"], stdin=PIPE, stdout=PIPE)
> >>> send_all(p, "5\n")
> >>> recv_some(p)
> ''
> >>> send_all(p, "6\n")
> >>> recv_some(p)
> ''
> 
> 

I also tried running the module as a program:

from asynchronous import *
p = Popen(["python", "increment.py"], stdin=PIPE, stdout=PIPE)

for n in [5, 7, 10, 4]:
send_all(str(p), n)
print(recv_some(p))

It gives:

prompt:~$ python subchronous_test.py
Traceback (most recent call last):
  File "subchronous_test.py", line 5, in 
send_all(str(p), n)
  File "/home/Somelauw/asynchronous.py", line 145, in send_all
while len(data):
TypeError: object of type 'int' has no len()
prompt:~$ Traceback (most recent call last):
  File "increment.py", line 4, in 
n = int(raw_input(n)) + 1
EOFError: EOF when reading a line
close failed in file object destructor:
Error in sys.excepthook:

Original exception was:

By the way:
synchronous is the name I gave to your module

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Re: how to get bit info

[Stephen Hansen]

On 6/17/10 1:29 PM, Grant Edwards wrote:
> On 2010-06-17, Stephen Hansen  wrote:
> 
> BIT_1 = 1 << 0
> BIT_2 = 1 << 1
> 
> ...
> 
>> Basically, those BIT_X lines are creating numbers which have *only* the
>> specified bit set. Then you do "byte & BIT_X", and that will return 0 if
>> the byte doesn't have the specified bit in it. You can then set the bit
>> with "byte | BIT_X", and unset the bit with "byte ^ BIT_X".
> 
> Just to clarify, "byte ^ BIT_X" inverts (toggles) bit X.
> 
> If you want to make sure bit X is a 0 (which is what people usually
> mean by "unset"), you do "byte & ~BIT_X"

Doh, you're correct. I got so used to the pattern of only ever flipping
the bit off after for some reason I knew it was on, like:

if blah & CONSTANT_A:
   do-stuff
   blah = blah ^ CONSTANT_A

That I forgot ^ was invert >_>

Ahem! Thanks for the correction.

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Re: Running a program from another program.

[Laurent Verweijen]

Op donderdag 17-06-2010 om 14:36 uur [tijdzone -0700], schreef Stephen
Hansen: 
> On 6/17/10 2:09 PM, Laurent Verweijen wrote:
> > It just gives me an empty string.
> > 
> > Python 2.6.5 (r265:79063, Apr 16 2010, 13:57:41) 
> > [GCC 4.4.3] on linux2
> > Type "help", "copyright", "credits" or "license" for more information.
>  from asynchronous import *
>  p = Popen(["python", "increment.py"], stdin=PIPE, stdout=PIPE)
>  send_all(p, "5\n")
>  recv_some(p)
> > ''
>  send_all(p, "6\n")
>  recv_some(p)
> > ''
> 
> Yes, that's how it signals the same situation. The point is: your
> subprocess isn't outputting anything. You sure its not crashing out, for
> instance?
> 

No, since it responds to the keyboard:

prompt:~$ python increment.py
05
64
53
44
55
66
75
64
53
44
55
66
7

All output is correct.

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How to print SRE_Pattern (regexp object) text for debugging purposes?

[dmtr]

I need to print the regexp pattern text (SRE_Pattern object ) for
debugging purposes, is there any way to do it gracefully? I've came up
with the following hack, but it is rather crude... Is there an
official way to get the regexp pattern text?

>>> import re, pickle
>>> r = re.compile('^abc$', re.I)
>>> r
<_sre.SRE_Pattern object at 0xb7e6a330>

>>> ds = pickle.dumps(r)
>>> ds
"cre\n_compile\np0\n(S'^abc$'\np1\nI2\ntp2\nRp3\n."

>>> re.search("\n\(S'(.*)'\n", ds).group(1)
'^abc$'
>>>

-- Cheers, Dmitry
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Re: Running a program from another program.

[Stephen Hansen]

On 6/17/10 2:40 PM, Laurent Verweijen wrote:
> Op donderdag 17-06-2010 om 14:36 uur [tijdzone -0700], schreef Stephen
> Hansen: 
>> On 6/17/10 2:09 PM, Laurent Verweijen wrote:
>>> It just gives me an empty string.
>>>
>>> Python 2.6.5 (r265:79063, Apr 16 2010, 13:57:41) 
>>> [GCC 4.4.3] on linux2
>>> Type "help", "copyright", "credits" or "license" for more information.
>> from asynchronous import *
>> p = Popen(["python", "increment.py"], stdin=PIPE, stdout=PIPE)
>> send_all(p, "5\n")
>> recv_some(p)
>>> ''
>> send_all(p, "6\n")
>> recv_some(p)
>>> ''
>>
>> Yes, that's how it signals the same situation. The point is: your
>> subprocess isn't outputting anything. You sure its not crashing out, for
>> instance?
>>
> 
> No, since it responds to the keyboard:

That doesn't really prove the point. There's all kinds of things that
can go wrong when you switch how you run a program.

Wrap your increment.py in like:

import sys
import traceback

try:
   ...
except:
   print >>sys.stderr, traceback.format_exc()

Then add the arg in your Popen, stderr=sys.stderr

And see if any exception is thrown.

The original error you got, and the empty string from the recipe, both
mean interpret.py is not returning any output. Why? Maybe its erroring
out-- the subprocess context is different then the context of running a
program from the keyboard. Or maybe you're not sending:

In your other thread you include an actual traceback:

Traceback (most recent call last):
  File "subchronous_test.py", line 5, in 
send_all(str(p), n)
  File "/home/Somelauw/asynchronous.py", line 145, in send_all
while len(data):
TypeError: object of type 'int' has no len()

The first argumetn to send_all should be the actual Popen subclass. The
second should be a string to send. I think that line really is intended
to be:

send_all(p, str(n)) # assuming 'n' is say, the number 5.

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Re: Processing HTML form

[Grant Edwards]

On 2010-06-17, Bradley Hintze  wrote:

> I am on Mac OSX 10.6, server is apache. If I do get this working we
> will move it to the main server which also serves apache, i believe.I
> dont think I want a whole new server, I'd like to serve from the
> apache framework if possible.

There are a couple different ways to integrate python code into
apache. You can use the normal CGI API where apache runs external
programs written in Python:

  http://docs.python.org/library/cgi.html
  
  http://gnosis.cx/publish/programming/feature_5min_python.html
  http://www.cs.virginia.edu/~lab2q/lesson_1/
  http://www.upriss.org.uk/python/PythonCourse.html
  
Or you can embed Python into apache so that it's faster and you can do
some more sophisticated stuff that's above my head:

  http://www.modpython.org/
  http://onlamp.com/pub/a/apache/2003/04/10/apacheandpython.html

More on both of the above at

  http://www.google.com/search?q=apache+python
  
There are people on the list far more experienced with Python+Apache
than I, so I'll leave it at that.

-- 
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  at   DECADENT SUBWAY SCENE.
  gmail.com
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Re: Py_single_input and the side-effects...

[Stephen Hansen]

On 6/17/10 2:32 PM, Mark Lawrence wrote:
> Where is the use of _ in a script documented, I've searched all over and
> can't find it, guess I don't have the Midas touch with google? :)

Its purely a convention, and one that crosses language-bounds, and isn't
entirely universal even given that.

It just means 'placeholder that I care naught for'; its not a feature,
there's no code or any /ability/ to use it. Its the same as any other
variable name.

It just happens to be a name that conveys no meaning while being short
and visually distinct: except to say you don't care about what value
ends up there, consider it thrown away.

That the interactive interpreter happens to store the last value in a
variable of the same name doesn't really mean anything.

-- 

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max time threads

[pacopyc]

Hi, I'm trying to work with threads and I need your help. This is
code:

from threading import Thread
from Queue import Queue
import time
import random

def test_fun (k,q,t):
time.sleep(t)
print "hello world from thread " + str(q.get()) + " (sleep time =
" + str(t) + " sec.)"
q.task_done()

queue = Queue()
for i in range (1,10):
queue.put(i)
for j in range(queue.qsize()):
num = random.randint(1,30)
worker = Thread(target=test_fun, args=(j,queue,num))
worker.setDaemon(True)
worker.start()
queue.join()


Execution:

hello world from thread 1 (sleep time = 5 sec.)
hello world from thread 2 (sleep time = 5 sec.)
hello world from thread 3 (sleep time = 6 sec.)
hello world from thread 4 (sleep time = 8 sec.)
hello world from thread 5 (sleep time = 10 sec.)
hello world from thread 6 (sleep time = 13 sec.)
hello world from thread 7 (sleep time = 18 sec.)
hello world from thread 8 (sleep time = 19 sec.)
hello world from thread 9 (sleep time = 20 sec.)

Some questions for you:

1) Why order is always the same (thread 1, thread 2, thread 3 
thread 9) and also seconds are always increasing? I don't understand.
2) I'd like to decide a max time for each thread. If max time = 7 sec.
I want to print only threads with sleep time <= 7 sec. How can I do?
Can you modify my code?

Thank you very much
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Re: Running a program from another program.

[Laurent Verweijen]

Op donderdag 17-06-2010 om 14:48 uur [tijdzone -0700], schreef Stephen
Hansen: 
> On 6/17/10 2:40 PM, Laurent Verweijen wrote:
> > Op donderdag 17-06-2010 om 14:36 uur [tijdzone -0700], schreef Stephen
> > Hansen: 
> >> On 6/17/10 2:09 PM, Laurent Verweijen wrote:
> >>> It just gives me an empty string.
> >>>
> >>> Python 2.6.5 (r265:79063, Apr 16 2010, 13:57:41) 
> >>> [GCC 4.4.3] on linux2
> >>> Type "help", "copyright", "credits" or "license" for more information.
> >> from asynchronous import *
> >> p = Popen(["python", "increment.py"], stdin=PIPE, stdout=PIPE)
> >> send_all(p, "5\n")
> >> recv_some(p)
> >>> ''
> >> send_all(p, "6\n")
> >> recv_some(p)
> >>> ''
> >>
> >> Yes, that's how it signals the same situation. The point is: your
> >> subprocess isn't outputting anything. You sure its not crashing out, for
> >> instance?
> >>
> > 
> > No, since it responds to the keyboard:
> 
> That doesn't really prove the point. There's all kinds of things that
> can go wrong when you switch how you run a program.
> 
> Wrap your increment.py in like:
> 
> import sys
> import traceback
> 
> try:
>...
> except:
>print >>sys.stderr, traceback.format_exc()
> 
> Then add the arg in your Popen, stderr=sys.stderr
> 
> And see if any exception is thrown.
> 
> The original error you got, and the empty string from the recipe, both
> mean interpret.py is not returning any output. Why? Maybe its erroring
> out-- the subprocess context is different then the context of running a
> program from the keyboard. Or maybe you're not sending:

I did exactly what you said, here is the result:

prompt:~$ python subchronous_test.py




Traceback (most recent call last):
  File "increment.py", line 7, in 
n = int(raw_input(str(n))) + 1
EOFError: EOF when reading a line

prompt$ close failed in file object destructor:
Error in sys.excepthook:

Original exception was:

> 
> In your other thread you include an actual traceback:
> 
> Traceback (most recent call last):
>   File "subchronous_test.py", line 5, in 
> send_all(str(p), n)
>   File "/home/Somelauw/asynchronous.py", line 145, in send_all
> while len(data):
> TypeError: object of type 'int' has no len()
> 
> The first argumetn to send_all should be the actual Popen subclass. The
> second should be a string to send. I think that line really is intended
> to be:
> 
> send_all(p, str(n)) # assuming 'n' is say, the number 5.
> 

You are right, I swapped the parameters, but even if I correct it, it
still gives the second error.

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Re: Convert .doc to .pdf

[Aahz]

In article <29a7823f-a3b1-466b-9876-553cb62c0...@w12g2000yqj.googlegroups.com>,
Thales   wrote:
>
>I need to convert some files from .doc to .pdf. I've googled it a
>little bit and all the solutions I've found used the OpenOffice API,
>but I can't use it.
>
>Anybody knows a library that I can use to do it?

Antiword:
http://www.winfield.demon.nl/
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"If you don't know what your program is supposed to do, you'd better not
start writing it."  --Dijkstra
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Re: Running a program from another program.

[Stephen Hansen]

On 6/17/10 3:06 PM, Laurent Verweijen wrote:
>>
>> In your other thread you include an actual traceback:
>>
>> Traceback (most recent call last):
>>   File "subchronous_test.py", line 5, in 
>> send_all(str(p), n)
>>   File "/home/Somelauw/asynchronous.py", line 145, in send_all
>> while len(data):
>> TypeError: object of type 'int' has no len()
>>
>> The first argumetn to send_all should be the actual Popen subclass. The
>> second should be a string to send. I think that line really is intended
>> to be:
>>
>> send_all(p, str(n)) # assuming 'n' is say, the number 5.
>>
> 
> You are right, I swapped the parameters, but even if I correct it, it
> still gives the second error.
> 

General rule of thumb: its best to never use the word "still" when it
comes to debugging Python and exceptions, unless you are absolutely
certain the exception is precisely the same.

I don't doubt that you may still get an exception on send_all; but there
is no way you're getting the *same* exception (that specific type error:
attempting to call len() on an integer) if you corrected your arguments.

You're getting the EOFError, because you're never sending anything to
the subprocess. You're not getting anything from the subprocess because
it never receives anything to send back. And apparently there's an error
on send, which is causing that problem, but that error is...?

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Re: How to print SRE_Pattern (regexp object) text for debugging purposes?

[MRAB]

dmtr wrote:

I need to print the regexp pattern text (SRE_Pattern object ) for
debugging purposes, is there any way to do it gracefully? I've came up
with the following hack, but it is rather crude... Is there an
official way to get the regexp pattern text?


import re, pickle
r = re.compile('^abc$', re.I)
r

<_sre.SRE_Pattern object at 0xb7e6a330>


ds = pickle.dumps(r)
ds

"cre\n_compile\np0\n(S'^abc$'\np1\nI2\ntp2\nRp3\n."


re.search("\n\(S'(.*)'\n", ds).group(1)

'^abc$'



>>> import re
>>> r = re.compile('^abc$', re.I)
>>> r.pattern
'^abc$'
>>> r.flags
2

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