plz sort this out

[piyali biswas]

Hi,
I am using networkx and pylab for creating a graph using a python script
abc.py.
I have saved the networkx folder in "C:/Python24/Lib/site-packages".
When I run the script from command prompt, it creates the graph and saves it
to the place I want to but when I write a python-cgi script and run it as
os.system('python abc.py')
it doesn't gives me any result.

I have included the path of my system using
os.environ['PATH'] = ".".

I also appended the path of networkx directory using
sys.path.append('C:/Python24/Lib/site-packages') as it seems to me that it
is a path related problem and the cgi result page shows error
(1) networkx *undefined*
(2)* *drawing undefined
(3) nx_pylab *undefined*
(4) matplotlib *undefined*
*(5)
raise RuntimeError("'%s' is not a writable dir; you must set
environment variable HOME to be
*
* a writable dir "%h)*
Can you please tell me how to enable cgi to run this program on runtime. I
have kept both the cgi script as well as python script in Apache/cgi-bin
folder.

Thanks,
Piyali
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Re: Getting started with python

[7stud]

On Apr 15, 9:49 pm, James Stroud <[EMAIL PROTECTED]> wrote:
> py> t = timeit.Timer(stmt=s)
> py> print "%.2f usec/pass" % (100 * t.timeit(number=10)/10)
> 40.88 usec/pass
>

What does this accomplish:

100 * t.timeit(number=10)/10

that the following doesn't accomplish:

10 * t.timeit(number=10)

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Re: Queue enhancement suggestion

[Peter Otten]

Paul Rubin wrote:

> I'd like to suggest adding a new operation
> 
>Queue.finish()
> 
> This puts a special sentinel object on the queue.  The sentinel
> travels through the queue like any other object, however, when
> q.get() encounters the sentinel, it raises StopIteration instead
> of returning the sentinel.  It does not remove the sentinel from
> the queue, so further calls to q.get also raise StopIteration.
> That permits writing the typical "worker thread" as
> 
>for item in iter(q.get): ...

I'd go one step further and implement Queue.__iter__(). The worker than
would do

for item in q: ...

> without having to mess with the task-counting stuff that recently got
> added to the Queue module.  The writing end of the queue simply
> calls .finish() when it's done adding items.
> 
> Someone in an earlier thread suggested
> 
>  # writing side
>  sentinel = object()
>  q.put(sentinel)
> 
>  ...
>  # reading side
>  for item in iter(q.get, sentinel): ...
> 
> however that actually pops the sentinel, so if there are a lot of
> readers then the writing side has to push a separate sentinel for
> each reader.  

I find that argument convincing.

Peter

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Re: Python and JMS?

[Jarek Zgoda]

Leonard J. Reder napisał(a):

> Yes indeed, we are using ActiveMQ and I did see the StomPy python
> package.  But I also saw that it said stomp was done as a student
> project that ended.  Maybe I will try hjb for now - all I need to do
> is listen for messages on a certain topic.
> 
> Maybe some of our internal people will pick stom and make it better for
> the future though.

I saw there are 2 libraries implementating stomp, the one mentioned by
you and one which looked a bit better. The protocol itself also doesn't
look very complicated, so this should be relatively easy to implement
client library for somebody who works with ActiveMQ on a daily basis.

-- 
Jarek Zgoda

"We read Knuth so you don't have to."
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Re: is laziness a programer's virtue?

[Rob Warnock]

Daniel Gee <[EMAIL PROTECTED]> wrote:
+---
| You fail to understand the difference between passive laziness and
| active laziness. Passive laziness is what most people have. It's
| active laziness that is the virtue. It's the desire to go out and /
| make sure/ that you can be lazy in the future by spending just a
| little time writing a script now. It's thinking about time
| economically and acting on it.
+---

Indeed. See Robert A. Heinlein's short story (well, actually just
a short section of his novel "Time Enough For Love: The Lives of
Lazarus Long") entitled "The Tale of the Man Who Was Too Lazy To
Fail". It's about a man who hated work so much that he worked
very, *very* hard so he wouldn't have to do any (and succeeded).


-Rob

-
Rob Warnock <[EMAIL PROTECTED]>
627 26th Avenue http://rpw3.org/>
San Mateo, CA 94403 (650)572-2607

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Re: Qt4 in ubuntu

[Marcpp]

On 15 abr, 22:54, "Diez B. Roggisch" <[EMAIL PROTECTED]> wrote:
> Marcpp schrieb:
>
> > Is possible install Qt4 pyqt4 under kubuntu?
> > Few times ago i tried to run pyqt in ubuntu (gnome) but i can't
> > do it.
>
> It's certainly possible. On ubuntu as well as on kubuntu. You can
> install all KDE and Qt stuff on ubuntu as well.
>
> But unless you are more specific what your actual problems were, you
> can't better help.
>
> Diez

Hi Diez, finally I can install a Qt4 on Kubuntu, but now I have
problems to install a Qt4Designer.
I'm introducing to Qt with python, why tutorial you recommend to me?

Thank you.

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Re: pyparsing Catch-22

[7stud]

Paul McGuire wrote:
> Me? Push?  Boy, a guy posts a couple of examples, tries to help some
> people that are stuck with a problem, and what does he get?  Called
> "pushy"?  Sheesh!

Hey, I never called you pushy!  Ok, maybe I sounded a little harsh--I
was pretty frustrated after all.  I guess I should have said something
along the lines of, "If you are going to promote pyparsing, it would
be nice to be able see what it is all about it."

> Fortunately, I get enough positive feedback from
> these posts that my feelings are pretty resilient these days.
>
> Anyway, thanks and point taken for the alert on this subject from the
> newbie's perspective.  When I first wrote these installations and
> started the pyparsing project on SF, I was fairly newb myself - I had
> to ask Dave Kuhlman to write setup.py for me!  So I assumed the target
> audience already knew the stuff I was having to learn.  I assumed that
> setup.py was just common knowledge among the Python world.
>
> I think your suggestion of a Wiki page on this subject should fill
> this gap neatly, especially since pyparsing is somewhat targetted at
> the newb and near-newb user, one that is struggling with regexp's or
> some other parsing technology, and just wants to get some basic code
> working.  The other posts in this thread contain plenty of material to
> start from.  Also, thanks for the Mac OS X point of view, most of my
> work is on Windows, and a little bit on Linux, but absolutely none on
> Mac.  And I see that I should not assume knowledge of tar, either, so
> I'll be sure to mention its destructive streak, in overwriting
> existing files with the same name as those in the archive.  Once
> untar'ed, there *is* a file named README, with an introduction and
> instructions to invoke setup.py properly.

Iol.  I read it:

-
Installation


Do the usual:

python setup.py install

(pyparsing requires Python 2.3.2 or later.)


Not much to go on--not even a mention of what directory you should be
in when you run that command.  Plus, you need to extract the files
from the .tar file first.

>
> I'm glad to see you perservered and got pyparsing installed.  You can
> also run pyparsing.py itself, which will run a simple SQL parser
> test.  If you have not yet found the docs or examples, *please* look
> over the sample code in the examples directory, and the class-level
> documentation in the htmldocs directory.  The docs directory should
> also include the materials from my PyCon'06 presentations.
>
> Please post back, either here or on the Pyparsing wiki discussion
> pages, and let me know how your pyparsing work is progressing.
>
> -- Paul (the developer, but you can call me "Paul")
>

I'm pretty facile with regex's, and after looking at some pyparsing
threads over the last week or so, I was interested in trying it.
However, all of the beginning examples use a Word() in the parse
expression, but I couldn't find an adequate explanation of what the
arguments to Word() are and what they mean.  I finally found the
information buried in one of the  many documents--the one called
"Using the Pyparsing Module".  If that seems like an obvious place to
look, I did start there, but I didn't find it at first.  I also
scoured the the wiki, and I looked in the file pycon06-
IntroToPyparsing-notes.pdf, which has this:

Basic Pyparsing
Words and Literals

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Re: Qt4 in ubuntu

[Diez B. Roggisch]

> 
> Hi Diez, finally I can install a Qt4 on Kubuntu, but now I have
> problems to install a Qt4Designer.
> I'm introducing to Qt with python, why tutorial you recommend to me?

Google for them. And use C++-tutorials, they can be easily translated to
python.

Diez
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Re: pyparsing Catch-22

[7stud]

On Apr 16, 2:06 am, "7stud" <[EMAIL PROTECTED]> wrote:
>

Hmmm.  My post got cut off.  Here's the rest of it:


I'm pretty facile with regex's, and after looking at some pyparsing
threads over the last week or so, I was interested in trying it.
However, all of the beginning examples use a Word() in the parse
expression, but I couldn't find an adequate explanation of what the
arguments to Word() are and what they mean.  I finally found the
information buried in one of the  many documents--the one called
"Using the Pyparsing Module".  If that seems like an obvious place to
look, I did start there, but I didn't find it at first.  I also
scoured the the wiki, and I looked in the file pycon06-
IntroToPyparsing-notes.pdf, which has this:


Basic Pyparsing
Words and Literals

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Re: Python Feature Request: Allow changing base of member indices to 1

[Javier Bezos]

Paddy,

>> Dijkstra's argument is obsolete, as it is based on
>> how array length was computed many years ago -- if
>> we have an array a = b..e, then the lenght of a
>> is e-b (half open range). Good at low level
>> programming.
>>
>> But a quarter of a century after we know concepts
>> are much better than low level programming and
>> explicit computations -- if we have an array
>> a = b..e, then the length of a should be a.length()
>> (or a.length(b,e)), and it is independent of

> Hi Javier,
> You seem to have missed out array *indexing*
> in your argument, or is array indexing obsolete?

Of course, it isn't, but it has evolved over the
past 25 years. When Djikstra wrote that, many
people (including me) was using a Spectrum---
Now we have OO programming to deal with concepts
and a more generic programming. So, to me it's
clear his _argument_ is very outdated and cannot
be applied directly and withot reservations to
modern languages like Python.

Javier
-
http://www.texytipografia.com 


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Re: pyparsing Catch-22

[7stud]

Basic Pyparsing
Words and Literals

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Re: pyparsing Catch-22

[7stud]

Word("ABC", "def") matches "C", "Added", "Beef"
but not "BB", "ACE", "ADD"

That is just baffling.  There's no explanation that the characters
specified in the first string are used to match the first char of a
word and that the characters specified in the second string are used
to match the rest of the word.   It would also help to know that if
only one string is specified, then the specified characters will be
used to match all the chars in a word.  I think you should add a
simple example to your wiki that explains all that.

Also, I think you should state right up front that alphas is a string
made up of the chars a-zA-z and that nums is a string made up of the
chars 0-9.   That way when someone sees Word(alphas), they will
understand exactly what that means.  Also since matching any char is a
pretty common thing, I think you should mention what printables is as
well.

In any case this is the example I applied pyparsing to:

Given .txt file(all on one line).  Requirement--construct a list from
the text:
-
mara = [
'U2FsdGVkX185IX5PnFbzUYSKg+wMyYg9',
'U2FsdGVkX1+BCxltXVTQ2+mo83Si9oAV0sasmIGHVyk=',
'U2FsdGVkX18iUS8hYBXgyWctqpWPypVz6Fj49KYsB8s='
]
---

and this is what I came up with:

--
from pyparsing import Word, alphas, commaSeparatedList

name = Word(alphas)
lookFor = name + "=" + "[" + commaSeparatedList + "]"

my_file = open("aaa.txt")
for line in my_file:
alist  = lookFor.parseString(line)

globals()[alist[0] ] = [ alist[3].strip("'"), alist[4].strip("'"),
alist[5].strip("'") ]

print mara[2]
--

Any tips?

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Re: File DB instead of real database?

[Bruno Desthuilliers]

Jia Lu a e'crit :
> Hello all
> 
>  I donot want to use a real DB like MySQL ... 

Whether MySQL is qualifies as a "real DB" is still an open question. But
you can use SQLite, which is an embedded SQL database.
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please sort this out

[piyali biswas]

Hi,
I am using networkx and pylab for creating a graph using a python script
abc.py.
I have saved the networkx folder in "C:/Python24/Lib/site-packages".
When I run the script from command prompt, it creates the graph and saves it
to the place I want to but when I write a python-cgi script and run it as
os.system('python abc.py')
it doesn't gives me any result.

I have included the path of my system using
os.environ['PATH'] = ".".

I also appended the path of networkx directory using
sys.path.append('C:/Python24/Lib/site-packages') as it seems to me that it
is a path related problem and the cgi result page shows error
(1) networkx *undefined*
(2)* *drawing undefined
(3) nx_pylab *undefined*
(4) matplotlib *undefined*
*(5)
raise RuntimeError("'%s' is not a writable dir; you must set
environment variable HOME to be
*
* a writable dir "%h)*
Can you please tell me how to enable cgi to run this program on runtime. I
have kept both the cgi script as well as python script in Apache/cgi-bin
folder.

Thanks,
Piyali
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Re: pyparsing Catch-22

[Marc 'BlackJack' Rintsch]

In <[EMAIL PROTECTED]>, 7stud wrote:

> However, all of the beginning examples use a Word() in the parse
> expression, but I couldn't find an adequate explanation of what the
> arguments to Word() are and what they mean.  I finally found the
> information buried in one of the  many documents--the one called
> "Using the Pyparsing Module".  If that seems like an obvious place to
> look, I did start there, but I didn't find it at first.

An obvious place should be the docstring of the `Word` class which says:

Token for matching words composed of allowed character sets.
Defined with string containing all allowed initial characters,
an optional string containing allowed body characters (if omitted,
defaults to the initial character set), and an optional minimum,
maximum, and/or exact length.

Ciao,
Marc 'BlackJack' Rintsch
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Re: is laziness a programer's virtue?

[Torben Ægidius Mogensen]

Dan Bensen <[EMAIL PROTECTED]> writes:

> Xah Lee wrote:
>> Laziness, Perl, and Larry Wall
>> When the sorcerer Larry Wall said “The three chief virtues of a
>> programmer are: Laziness, Impatience and Hubris”, he used the word
>> “laziness” to loosely imply “natural disposition that results in being
>> economic”.
>
> Programming by definition is the process of automating repetitive
> actions to reduce the human effort required to perform them.  A good
> programmer faced with a hard problem always looks for ways to make
> his|her job easier by delegating work to a computer.  That's what
> Larry means.  Automation is MUCH more effective than repetition.

Indeed.  A programmer is someone who, after doing similar tasks by
hand a few times, writes a program to do it.  This extends to
programming tasks, so after writing similar programs a few times, a
(good) programmer will use programming to make writing future similar
programs easier.  This can be by abstracting the essence of the task
into library functions so new programs are just sequences of
parameterized calls to these, or it can be by writing a program
generator (such as a parser generator) or it can be by designing a
domain-specific language and writing a compiler or interpreter for
this.

Torben

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string methods of a str subclass

[Daniel Nogradi]

I am probably misunderstanding some basic issue here but this
behaviour is not what I would expect:



Python 2.4 (#1, Mar 22 2005, 21:42:42)
[GCC 3.3.5 20050117 (prerelease) (SUSE Linux)] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> class mystr( str ):
... pass
...
>>> x = mystr( 'x' )
>>> isinstance( x, mystr )
True
>>> isinstance( x.strip( ), mystr )
False
>>>


Why is the strip( ) method returning something that is not a mystr
instance? I would expect all methods operating on a string instance
and returning another string instance to correctly operate on a mystr
instance and return a mystr instance. How would I achieve something
like this without manually copying all string returning methods from
str and stuffing the result to mystr( ) before returning?
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Re: Queue enhancement suggestion

[Antoon Pardon]

On 2007-04-16, Paul Rubin  wrote:
> I'd like to suggest adding a new operation
>
>Queue.finish()
>
> This puts a special sentinel object on the queue.  The sentinel
> travels through the queue like any other object, however, when
> q.get() encounters the sentinel, it raises StopIteration instead
> of returning the sentinel.  It does not remove the sentinel from
> the queue, so further calls to q.get also raise StopIteration.
> That permits writing the typical "worker thread" as
>
>for item in iter(q.get): ...
>

The problem is this doesn't work well if you have multiple producers.
One producer can be finished while the other is still putting values
on the queue.

The solution I have been thinking on is the following.

Add an open and close operation. Only threads that have the queue
open can access it. The open call should specify whether you
want to read or write to the queue or both. When all writers
have closed the queue and the queue is empty a q.get will
raise an exception. This may be done by putting a sentinel
on the queue when the last writer closed the queue.

-- 
Antoon Pardon
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Re: Method calls and stack consumption

[Peter Otten]

Martin Manns wrote:

> Thanks for pointing out the oversimplified nature of the original
> example.I hope that the following one clarifies the problem.
> 
> (I do not know, what has to be stored on the stack, but it should not be
> that much, because all recursion calls originate from inside the return
> statement.)

> class Node(object):
> def __init__(self):
> self.state = abs(randint(1,1000))
> def GetDepState(self):
> return self.state + max(s.GetDepState() for s in S[self])
> 
> class ConditionalBreakNode(Node):
> def GetDepState(self):
> if randint(1,5) > 1:
> return Node.GetDepState(self)
> else:
> return self.state

Have you investigated the libraries available for that kind of problem? (No,
I don't know them) Maybe one of them provides an implementation that does
not depend on the stack.

On the other hand, if the above is the "natural" expression of your problem,
why not give stackless a try?

Peter
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ANN: PyQt v4.2 (Python Bindings for Qt)

[Phil Thompson]

Riverbank Computing is pleased to announce the release of PyQt v4.2 available 
from http://www.riverbankcomputing.co.uk/pyqt/.

The highlights of this release include:

- The ability to write widget plugins for Qt Designer in Python.
- Integration of the Python command shell and the Qt event loop.  This allows
  developers to call Qt functions dynamically on a running application.
- Integration of the Qt event loop with the standard Python DBus bindings
  available from www.freedesktop.org.

PyQt is a comprehensive set of Qt bindings for the Python programming language 
and supports the same platforms as Qt (Windows, Linux and MacOS/X).  Like Qt, 
PyQt is available under the GPL and a commercial license.

See http://www.riverbankcomputing.com/Docs/PyQt4/html/classes.html for the 
class documentation.

PyQt v4 supports Qt v4 (http://www.trolltech.com/products/qt/index.html).  
PyQt v3 is still available to support earlier versions of Qt.

PyQt v4 is implemented as a set of 10 extension modules containing 
approximately 400 classes and 6,000 functions and methods.

QtCore
The non-GUI infrastructure including event loops, threads, i18n, Unicode,
signals and slots, user and application settings.

QtGui
A rich collection of GUI widgets.

QtNetwork
A set of classes to support TCP and UDP socket programming and higher
level protocols (eg. HTTP).

QtOpenGL
A set of classes that allows PyOpenGL to render onto Qt widgets.

QtSql
A set of classes that implement SQL data models and interfaces to industry
standard databases.  Includes an implementation of SQLite.

QtSvg
A set of classes to render SVG files onto Qt widgets.

QtTest
A set of classes to automate unit testing of PyQt applications and GUIs.

QtXML
A set of classes that implement DOM and SAX parsers.

QtAssistant
A set of classes that enables the Qt Assistant online help browser to be
integrated with an application.

QAxContainer
A set of classes for Windows that allows the integration of ActiveX
controls and COM objects.

A Windows installer is provided for the GPL version of PyQt to be used with 
the GPL version of Qt v4 (http://www.trolltech.com/download/qt/windows.html). 
It enabes a complete PyQt environment to be installed on Windows without the 
need for a C++ compiler.

PyQt includes the pyuic utility which generates Python code to implement user 
interfaces created with Qt Designer in the same way that the uic utility 
generates C++ code.  It is also able to load Designer XML files dynamically.
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Compare regular expressions

[Thomas Dybdahl Ahle]

Hi, I'm writing a program with a large data stream to which modules can 
connect using regular expressions.

Now I'd like to not have to test all expressions every time I get a line, 
as most of the time, one of them having a match means none of the others 
can have so.

But ofcource there are also cases where a regular expression can 
"contain" another expression, like in:
"^strange line (\w+) and (\w+)$" and "^strange line (\w+) (?:.*?)$" in 
which case I'd like to first test the seccond and only if it mathces test 
the seccond.

Do anybody know if such a test is possible?
if exp0.contains(exp1): ...
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Re: string methods of a str subclass

[7stud]

On Apr 16, 3:28 am, "Daniel Nogradi" <[EMAIL PROTECTED]> wrote:
> I am probably misunderstanding some basic issue here but this
> behaviour is not what I would expect:
>
> Python 2.4 (#1, Mar 22 2005, 21:42:42)
> [GCC 3.3.5 20050117 (prerelease) (SUSE Linux)] on linux2
> Type "help", "copyright", "credits" or "license" for more information.>>> 
> class mystr( str ):
>
> ... pass
> ...
>
> >>> x = mystr( 'x' )
> >>> isinstance( x, mystr )
> True
> >>> isinstance( x.strip( ), mystr )
> False
>
> Why is the strip( ) method returning something that is not a mystr
> instance? I would expect all methods operating on a string instance
> and returning another string instance to correctly operate on a mystr
> instance and return a mystr instance. How would I achieve something
> like this without manually copying all string returning methods from
> str and stuffing the result to mystr( ) before returning?

class A(object):
def __init__(self, s):
self.s = s
def strip(self):
return 2

class mystr(A):
pass

x = mystr("x")
print isinstance(x, mystr)
print isinstance(x.strip(), mystr)


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Re: Portably generating infinity and NaN

[Michael Hoffman]

Paul Rubin wrote:
> [EMAIL PROTECTED] writes:
>> But PEP 754 will only work for architectures supporting IEEE 754.  I realize
>> that's the vast majority of systems, but aren't there still a few Crays and
>> VMS machines out there?  (Do those architectures support NaN and Inf?)
> 
> I wouldn't worry about it.  There are Python subsystems (like threads) that
> don't work on certain OS's, fine, total portability means not being able to
> rely on them, and that's ok.  I doubt any Crays are still running, or at least
> running any numerical code written in Python.  Same for VMS.

Do these systems provide infinities or NaN? If so, then fpconst could be 
extended to include them.
-- 
Michael Hoffman
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Re: string methods of a str subclass

[Duncan Booth]

"Daniel Nogradi" <[EMAIL PROTECTED]> wrote:

> Why is the strip( ) method returning something that is not a mystr
> instance? I would expect all methods operating on a string instance
> and returning another string instance to correctly operate on a mystr
> instance and return a mystr instance.

Why would you expect that?
Would you expect the __str__ and__repr__ methods also to return a mystr 
instance? If not those, then which other ones might also be excluded?
Is x.encode('zip') still a mystr instance or an encoded byte-string?

> How would I achieve something
> like this without manually copying all string returning methods from
> str and stuffing the result to mystr( ) before returning?

You don't without wrapping all the affected methods. It doesn't need to 
involve manual copying though: you have a programming language available so 
just write a list of method names and then some code to wrap them 
automatically.
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How to generate a continuous string

[人言落日是天涯，望极天涯不见家]

How to generate a continuous string, like this
"aaa"
the number of characters is dynamic. Is there a module or function
implement this string ?
such as: duplicate_string(char, num)

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newbie question: how to read back the dictionary from a file?

[lancered]

Hi Dear all,

I have some data here in the form of a dictionary, called "vdic". Then
I write them to a data file "f" using   the write function as
f.write(str(vdic)).  The keys of this dictionary are integers and
values are float numbers. Something like this:

{ 1: 0.00951486513347, 2: 0.0388123556019, ... ...}

Now, I want to read these data back in another function.  Of course, I
could parse the string little by little, e.g, first read a "{", then
loop read a int, then read a ":", then a float etc etc... Since it is
written out with standard python builtin functions,  I guess there may
be some more direct method than this, say a function in some modules?
Could someone give me a hint?

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Re: string methods of a str subclass

[7stud]

On Apr 16, 3:28 am, "Daniel Nogradi" <[EMAIL PROTECTED]> wrote:
> I would expect all methods operating on a string instance
> and returning another string instance

Ok, then this:

class A(object):
def __init__(self, s):
self.s = s
def strip(self):
return self.s

class mystr(A):
pass

x = mystr("x")
print isinstance(x, mystr)
print isinstance(x.strip(), mystr)


"x" is a string, and that is what gets passed to the base class's
__init__ method, and that is what strip() operates on.


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Rapyd-Tk Pmw Notebook tutorial

[boriq]

Hello,

could anybody be so kind and write me a small tutorial about "how to
create a Pmw notebook with 3 tabs each containing 5 checkboxes" with
the help of Rapyd-Tk?

Thanks in advance
rg,
boris

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Re: How to generate a continuous string

[Marc 'BlackJack' Rintsch]

In <[EMAIL PROTECTED]>,
人言落日是天涯，望极天涯不见家 wrote:

> How to generate a continuous string, like this
> "aaa"
> the number of characters is dynamic. Is there a module or function
> implement this string ?
> such as: duplicate_string(char, num)

Even easier: multiply the string by a number.

In [12]: 'a' * 5
Out[12]: 'a'

Ciao,
Marc 'BlackJack' Rintsch
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Re: How to generate a continuous string

[[EMAIL PROTECTED]]

On 16 avr, 12:03, "人言落日是天涯，望极天涯不见家" <[EMAIL PROTECTED]> wrote:
> How to generate a continuous string, like this
> "aaa"
> the number of characters is dynamic. Is there a module or function
> implement this string ?
> such as: duplicate_string(char, num)

>>> "a"*10
'aa'
>>> "a"*20
''
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Re: How to generate a continuous string

[Michael Bentley]

On Apr 16, 2007, at 5:03 AM, 人言落日是天涯，望极天涯不 
见家 wrote:

> How to generate a continuous string, like this
> "aaa"
> the number of characters is dynamic. Is there a module or function
> implement this string ?
> such as: duplicate_string(char, num)

It's even easier than that -- just multiply:

 >>> 'a' * 32
''

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Re: newbie question: how to read back the dictionary from a file?

[Amit Khemka]

On 16 Apr 2007 03:03:40 -0700, lancered <[EMAIL PROTECTED]> wrote:
> Hi Dear all,
>
> I have some data here in the form of a dictionary, called "vdic". Then
> I write them to a data file "f" using   the write function as
> f.write(str(vdic)).  The keys of this dictionary are integers and
> values are float numbers. Something like this:
>
> { 1: 0.00951486513347, 2: 0.0388123556019, ... ...}
>
> Now, I want to read these data back in another function.  Of course, I
> could parse the string little by little, e.g, first read a "{", then
> loop read a int, then read a ":", then a float etc etc... Since it is
> written out with standard python builtin functions,  I guess there may
> be some more direct method than this, say a function in some modules?
> Could someone give me a hint?
>

Check out cPickle or shelve modules.

Cheers,
-- 

Amit Khemka -- onyomo.com
Home Page: www.cse.iitd.ernet.in/~csd00377
Endless the world's turn, endless the sun's Spinning, Endless the quest;
I turn again, back to my own beginning, And here, find rest.
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Re: How to generate a continuous string

[Amit Khemka]

On 16 Apr 2007 03:03:26 -0700, 人言落日是天涯，望极天涯不见家 <[EMAIL PROTECTED]> wrote:

How to generate a continuous string, like this
"aaa"
the number of characters is dynamic. Is there a module or function
implement this string ?
such as: duplicate_string(char, num)


mystr = mychar*n
n: Integer (number of times you want to duplicate)

Cheers,

--

Amit Khemka -- onyomo.com
Home Page: www.cse.iitd.ernet.in/~csd00377
Endless the world's turn, endless the sun's Spinning, Endless the quest;
I turn again, back to my own beginning, And here, find rest.
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Re: newbie question: how to read back the dictionary from a file?

[7stud]

On Apr 16, 4:03 am, "lancered" <[EMAIL PROTECTED]> wrote:
> Hi Dear all,
>
> I have some data here in the form of a dictionary, called "vdic". Then
> I write them to a data file "f" using   the write function as
> f.write(str(vdic)).  The keys of this dictionary are integers and
> values are float numbers. Something like this:
>
> { 1: 0.00951486513347, 2: 0.0388123556019, ... ...}
>
> Now, I want to read these data back in another function.  Of course, I
> could parse the string little by little, e.g, first read a "{", then
> loop read a int, then read a ":", then a float etc etc... Since it is
> written out with standard python builtin functions,  I guess there may
> be some more direct method than this, say a function in some modules?
> Could someone give me a hint?

Try:

import shelve

s = shelve.open("newFile.dat")
s["d"] = {"red":2, 3:"blue", 2.5:"x"}
s.close()

s = shelve.open("newFile.dat")
print s["d"]
my_dict = s["d"]
print my_dict[2.5]

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Re: newbie question: how to read back the dictionary from a file?

[7stud]

s.close()

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Signal Handlers

[Robert Rawlins - Think Blue]

Hello Guys,

 

Thanks again for all the help you've given me this past week, things are
moving briskly and my class library is building nicely and seems to be
working well :-D

 

Now, I'm working with an API for another piece of software today, and the
API documentation details the signals that are broadcast upon particular
events, which I need to listen for and then handle.

 

Here is an example:

 

   void RemoteDeviceFound(string address, uint32 class, int16
rssi)

 

   This signal will be send every time an inquiry result

   has been found by the service daemon. In general they

   only appear during a device discovery.

 

Now, how do I listen for this signal? I've seen a couple of examples where
by they import the signal module, and then to
signal.signal(RemoteDeviceFound, myFunctionToCall) but the python
documentation seemed to think that this would be limited to 2 arguments,
when I've obviously got 3 of them.

 

Perhaps I've got my wires crossed, if it's really that simple then great.
However, where about in my application should I declare that signal
listener?

 

Thanks,

 

Rob

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Boost Problem! Boost.Build not found

[Soren]

Hi!

I'm trying to extend my python program with some C++ code. Right now
I've spent hours just trying to get boost to work!

I'm trying to get the example hello.cpp to work.

Using Windows XP and Visual Studio 8   (.NET 2005)

I've set BOOST_BUILD_PATH = C:\boost\boost_1_33_1  (where i installed
boost)

I've changed the jamrules in C:\boost\boost_1_33_1\libs\python\example
\tutorial to

path-global BOOST_ROOT : C:\boost\boost_1_33_1 ;



No matter what I do i always get:

C:\boost\boost_1_33_1\libs\python\example\tutorial>bjam -sTOOLS=vc-8_0


Unable to load Boost.Build: could not find "boost-build.jam"
---
Attempted search from C:\boost\boost_1_33_1\libs\python\example
\tutorial up to t
he root and in these directories from BOOST_BUILD_PATH and BOOST_ROOT:
C:\boost\boost_1_
33_1.
Please consult the documentation at 'http://www.boost.org'.

Can anyone please tell me what I am doing wrong?? Theres no tutorial
on how to make a boost-build.jam file.. and as I understand I don't
need one as long as I set BOOST_BUILD_PATH ..

Any help is apprecieated!!

Thanks!,
Soren

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Re: ctypes and pointers

[per9000]

[This might be a double posting, if it isn't my previous post was
lost]

Look up "restype" in the ctypes library - it sets the return type from
a function. You may want to set it to c_void_p of something similar,
instead of the default int.

I made a similar discovery in my blog -
http://www.pererikstrandberg.se/blog/index.cgi?page=PythonCansiCombo
.

This example loads the function find_root from the dll
root_find_lib.dll into the variable "find". the restype of find is
then set to a c_double. This means that the item returned from C is a
C_double and not the default int.
root_find_lib = windll.LoadLibrary("root_find_lib.dll")
find = root_find_lib.find_root
find.restype = c_double


You may already know this but 243666016 == 0E860C60 in different
bases.

HTH,
Per

[:)]-|--<

--

Per Erik Strandberg
.NET Architect - Optimization
Tomlab Optimization Inc.
http://tomopt.com/tomnet/





On 14 Apr, 19:25, "Diez B. Roggisch" <[EMAIL PROTECTED]> wrote:
> Hi,
>
> I'm working under mac os x with the OpenCV-library that I load viactypes.
>
>  From a ObjectiveC-methodcall I get an integer, that "really" is a
> pointer to an IplImage-structure.
>
> I've got a function that takes such a pointer. But I don't find a way to
> pass it to that very function.
>
> These are the relevant parts of my code:
>
>  cvImage = self._f.cvImage()
>  print "Address of IplImage: %x" % cvImage
>  cvImage = c_void_p(cvImage)
>  print cvImage
>  cvImage2 = macopencv.cvCloneImage(cvImage)
>
> The output is
>
> 2007-04-14 19:22:53.910 SequenceGrabberTest[5320] Returning IplImage at
> Address of IplImage: e860c60
> e860c60
> c_void_p(243666016)
> 2007-04-14 19:22:53.915 SequenceGrabberTest[5320] Exception raised
> during posting of notification.  Ignored.  exception:
> exceptions.ValueError: depythonifying 'pointer', got 'int'
>
> The first line is actually from the ObjectivC-method, a log-statement.
>
> As one can see, the pointer is passed back as integer.
>
> But then I'm stuck.
>
> Any suggestions would be appreciated!
>
> diez


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how to combine two applications in pygtk

[PARIMALA KALAVALA]

hi,

   I want to know how to integrate two applications in pygtk. Should we
add any  header files in the main program or import any modules.
   also if we need to import any modules then how to convert the
application in a module.
   Pls reply to this mail as soon as possible.
Thank you.
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Re: Boost Problem! Boost.Build not found

[Rob Wolfe]

Soren wrote:

> Unable to load Boost.Build: could not find "boost-build.jam"
> ---
> Attempted search from C:\boost\boost_1_33_1\libs\python\example
> \tutorial up to t
> he root and in these directories from BOOST_BUILD_PATH and BOOST_ROOT:
> C:\boost\boost_1_
> 33_1.
> Please consult the documentation at 'http://www.boost.org'.
>
> Can anyone please tell me what I am doing wrong?? Theres no tutorial
> on how to make a boost-build.jam file.. and as I understand I don't
> need one as long as I set BOOST_BUILD_PATH ..

Try to create boost-build.jam file like this:

# boost-build.jam
boost-build C:\boost\boost_1_33_1\tools\build\v1 ;

--
HTH,
Rob

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Re: is laziness a programer's virtue?

[Torben Ægidius Mogensen]

[EMAIL PROTECTED] (Rob Warnock) writes:

> Daniel Gee <[EMAIL PROTECTED]> wrote:
> +---
> | You fail to understand the difference between passive laziness and
> | active laziness. Passive laziness is what most people have. It's
> | active laziness that is the virtue. It's the desire to go out and /
> | make sure/ that you can be lazy in the future by spending just a
> | little time writing a script now. It's thinking about time
> | economically and acting on it.
> +---
>
> Indeed. See Robert A. Heinlein's short story (well, actually just
> a short section of his novel "Time Enough For Love: The Lives of
> Lazarus Long") entitled "The Tale of the Man Who Was Too Lazy To
> Fail". It's about a man who hated work so much that he worked
> very, *very* hard so he wouldn't have to do any (and succeeded).

You can also argue that the essence of progress is someone saying
"Hey, there must be an easier way to do this!".

Torben

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Re: Boost Problem! Boost.Build not found

[Soren]

On 16 Apr., 12:53, "Rob Wolfe" <[EMAIL PROTECTED]> wrote:
> Soren wrote:
> > Unable to load Boost.Build: could not find "boost-build.jam"
> > ---
> > Attempted search from C:\boost\boost_1_33_1\libs\python\example
> > \tutorial up to t
> > he root and in these directories from BOOST_BUILD_PATH and BOOST_ROOT:
> > C:\boost\boost_1_
> > 33_1.
> > Please consult the documentation at 'http://www.boost.org'.
>
> > Can anyone please tell me what I am doing wrong?? Theres no tutorial
> > on how to make a boost-build.jam file.. and as I understand I don't
> > need one as long as I set BOOST_BUILD_PATH ..
>
> Try to create boost-build.jam file like this:
>
> # boost-build.jam
> boost-build C:\boost\boost_1_33_1\tools\build\v1 ;
>
> --
> HTH,
> Rob


Hi Rob, Thanks for answer!

It did solve the error... but created a new one:

C:\boost\boost_1_33_1\libs\python\example\tutorial>bjam -sTOOLS=vc-8_0

Unable to load Boost.Build: could not find build system.
-
C:\boost\boost_1_33_1\libs\python\example\boost-build.jam attempted to
load the
build system by invoking

   'boost-build C:/boost/boost_1_33_1/tools/build/v1 ;'

but we were unable to find "bootstrap.jam" in the specified directory
or in BOOST_BUILD_PATH (searching C:\boost\boost_1_33_1, C:/boost/
boost_1_33_1/t
ools/build/v1).


What is boostrap.jam? I haven't seen that one mentioned in the short
tutorial...

Thanks!,
Soren

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Re: Boost Problem! Boost.Build not found

[Soren]

On 16 Apr., 12:53, "Rob Wolfe" <[EMAIL PROTECTED]> wrote:
> Soren wrote:
> > Unable to load Boost.Build: could not find "boost-build.jam"
> > ---
> > Attempted search from C:\boost\boost_1_33_1\libs\python\example
> > \tutorial up to t
> > he root and in these directories from BOOST_BUILD_PATH and BOOST_ROOT:
> > C:\boost\boost_1_
> > 33_1.
> > Please consult the documentation at 'http://www.boost.org'.
>
> > Can anyone please tell me what I am doing wrong?? Theres no tutorial
> > on how to make a boost-build.jam file.. and as I understand I don't
> > need one as long as I set BOOST_BUILD_PATH ..
>
> Try to create boost-build.jam file like this:
>
> # boost-build.jam
> boost-build C:\boost\boost_1_33_1\tools\build\v1 ;
>
> --
> HTH,
> Rob


Hi Rob, Thanks for the answer!

It did solve the error.. but produced a new one:

C:\boost\boost_1_33_1\libs\python\example\tutorial>bjam -sTOOLS=vc-8_0
Unable to load Boost.Build: could not find build system.
-
C:\boost\boost_1_33_1\libs\python\example\boost-build.jam attempted to
load the
build system by invoking

   'boost-build C:/boost/boost_1_33_1/tools/build/v1 ;'

but we were unable to find "bootstrap.jam" in the specified directory
or in BOOST_BUILD_PATH (searching C:\boost\boost_1_33_1, C:/boost/
boost_1_33_1/t
ools/build/v1).

What is bootstrap.jam? .. Haven't seen that one in the short
tutorial...

Thanks alot!,
Soren

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Re: Getting started with python

[Steve Holden]

James Stroud wrote:
> Steve Holden wrote:
>> You'd be worth more if you'd used elif and omitted the continue 
>> statements, but for a first solution it's acceptable.
> 
> Depends on what you are after.
> 
> py> s = """
> ... for i in xrange(1,101):
> ...   if not i % 15:
> ... continue
> ...   if not i % 5:
> ... continue
> ...   if not i % 3:
> ... continue
> ...   else:
> ... pass
> ... """
> py> t = timeit.Timer(stmt=s)
> py> print "%.2f usec/pass" % (100 * t.timeit(number=10)/10)
> 40.49 usec/pass
> py> s = """
> ... for i in xrange(1,101):
> ...   if not i % 15:
> ... pass
> ...   elif not i % 5:
> ... pass
> ...   elif not i % 3:
> ... pass
> ...   else:
> ... pass
> ... """
> py> t = timeit.Timer(stmt=s)
> py> print "%.2f usec/pass" % (100 * t.timeit(number=10)/10)
> 40.88 usec/pass
> 

To be strictly comparable you should have pass statements before the 
continue statements as well.  Ignoring that, clearly it's well worth 
saving that extra 390 nanoseconds each time round the loop.

Repeat after me "premature optimization is the root of all evil".

   http://en.wikipedia.org/wiki/Optimization_(computer_science)

regards
  Steve
-- 
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Skype: holdenweb http://del.icio.us/steve.holden
Recent Ramblings   http://holdenweb.blogspot.com

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Re: ctypes and pointers

[Diez B. Roggisch]

per9000 wrote:

> [This might be a double posting, if it isn't my previous post was
> lost]
> 
> Look up "restype" in the ctypes library - it sets the return type from
> a function. You may want to set it to c_void_p of something similar,
> instead of the default int.
> 
> I made a similar discovery in my blog -
> http://www.pererikstrandberg.se/blog/index.cgi?page=PythonCansiCombo
> .
> 
> This example loads the function find_root from the dll
> root_find_lib.dll into the variable "find". the restype of find is
> then set to a c_double. This means that the item returned from C is a
> C_double and not the default int.
> root_find_lib = windll.LoadLibrary("root_find_lib.dll")
> find = root_find_lib.find_root
> find.restype = c_double

I found the solution to be 

X.from_address(address)

where X is some ctypes.Structure

Diez
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Import From SubFolder

[Robert Rawlins - Think Blue]

Chaps,

 

Is it possible to import a module from a subdirectory in my application? I
can only seem to get it to import from a single directory, but keeping all
my files and classes in the same directory becomes a little sloppy.

 

Thanks,

 

Rob 

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Re: File DB instead of real database?

[Sebastian Bassi]

On 13 Apr 2007 21:14:36 -0700, Jia Lu <[EMAIL PROTECTED]> wrote:
>  I donot want to use a real DB like MySQL ... But I need something to
> save about more than 1000 articles.
>  Is there any good ways?

SQLite is a good option, as you were told. But what about put them in
a dictionary and then cPickle it to disk? (using 2 as optimization
setting in cPickle command).
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How to tell whetehr Python script called as CGI or from command line?

[rowan]

I'm writing a Python script that can either be called as a Cron job or
as a web page (i.e. as a CGI in response to an HTTP request). This is
to process the mailboxes on my web server (to which I don't have
command line access) to remove old messages. How do I find out whether
the script has been called as a Cron job or as a CGI? I need to know
this so I can format the output correctly, e.g. if this is a web
request I need to start the output with "Content-type: text/html\n
\n", to do newlines by "" or "" etc.

Can I just access some header line which will always have a value in a
web request, but which will be None if running from the command line
or as a Cron job, or something similar? How?

Thanks - Rowan

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Re: pyparsing Catch-22

[Paul McGuire]

On Apr 16, 3:27 am, "7stud" <[EMAIL PROTECTED]> wrote:
> 
> Any tips?

7stud -

Here is the modified code, followed by my comments.

Oh, one general comment - you mention that you are quite facile with
regexp's.  pyparsing has a slightly different philosophy from that of
regular expressions, especially in the areas of whitespace skipping
and backtracking.  pyparsing will automatically skip whitespace
between parsing expressions, whereas regexp's require explicit
'\s*' (unless you specify the magic "whitespace between elements
allowed" attribute which I don't remember its magic attribute
character at the moment, but I rarely see regexp examples use it).
And pyparsing is purely a left-to-right recursive descent parser
generator.  It wont look ahead to the next element past a repetition
operation to see when to stop repeating.  There's an FAQ on this on
the wiki.

--
from pyparsing import Word, alphas, commaSeparatedList, delimitedList,
sglQuotedString, removeQuotes

name = Word(alphas)
lookFor = name + "=" + "[" + commaSeparatedList + "]"

# comment #0
my_file = """\
mara = [
'U2FsdGVkX185IX5PnFbzUYSKg+wMyYg9',
'U2FsdGVkX1+BCxltXVTQ2+mo83Si9oAV0sasmIGHVyk=',
'U2FsdGVkX18iUS8hYBXgyWctqpWPypVz6Fj49KYsB8s='
]"""
my_file = "".join(my_file.splitlines())
# uncomment next line once debugging of grammar is finished
# my_file = open("aaa.txt").read()


# comment #1
#~ my_file = open("aaa.txt")
#~ for line in my_file:
for line in [my_file,]:
alist = lookFor.parseString(line)

globals()[alist[0] ] = [ alist[3].strip("'"), alist[4].strip("'"),
alist[5].strip("'") ]


# comment #2
def stripSingleQuotes(s):
return s.strip("'")
globals()[alist[0] ] = map(stripSingleQuotes, alist[3:-1] )

print mara[2]
mara = None


# comment #3
lookFor = name.setResultsName("var") + "=" + "[" + \
commaSeparatedList.setResultsName("listValues") + "]"
alist = lookFor.parseString(my_file)

# evaluate parsed assignment
globals()[ alist.var ] = map(stripSingleQuotes, alist.listValues )
print len(mara), mara[1]


# comment #4
lookFor = name.setResultsName("var") + "=" + "[" + \
delimitedList( sglQuotedString.setParseAction(removeQuotes) )\
.setResultsName("listValues") + "]"

alist = lookFor.parseString(my_file)
globals()[ alist.var ] = list( alist.listValues )
print len(mara), mara[1]

--
Comment #0:
When I am debugging a pyparsing application, I find it easier to embed
the input text, or a subset of it, into the program itself using a
triple-quoted string.  Then later, I'll go back and change to reading
data from an input file.  Purely a matter of taste, but it simplifies
posting to mailing lists and newsgroups.

Comment #1:
Since you are going line by line in reading the input file, be *sure*
you have the complete assignment expression on each line.  Since
pyparsing will read past line breaks for you, and since your input
file contains only this one assignment, you might be better off
calling parseString with: alist =
lookFor.parseString( my_file.read() )

Comment #2:
Your assignment of the "mara" global is a bit clunky on two fronts:
- the explicit accessing of elements 3,4, and 5
- the repeated calls to strip("'")
You can access the pyparsing returned tokens (passed as a ParseResults
object) using slices.  In your case, you want the elements 3 through
n-1, so alist[3:-1] will give you this.  It's nice to avoid hard-
coding things like list lengths and numbers of list elements.  Note
that you can also use len to find out the length of the list.

As for calling strip("'") for each of these elements, have you learned
to use Python's map built-in yet?  Define a function or lambda that
takes a single element, return from the function what you want done
with that element, and then call map with that function, and the list
you want to process.  This modified version of your call is more
resilient than the original.

Comment #3:
Personally, I am not keen on using too much explicit indexing into the
returned results.  This is another area where pyparsing goes beyond
typical lexing and tokenizing.  Just as you can assign names to fields
in regexp's, pyparsing allows you to give names to elements within the
parsed results.  You can then access these by name, using either dict
or object attribute syntax.  This gets rid of most if not all of the
magic numbers from your code, and makes it yet again more resilient in
light of changes in the future.  (Say for example you decided to
suppress the "=", "[", and "]" punctuation from the parsed results.
The parsing logic would remain the same, but the returned tokens would
contain only the significant content, the variable name and list
contents.  Using explicit list indexing would force you to renumber
the list elements you are extracting, but with results names, no
change would be required.)

Comment #4:
I thought I'd show you an alternative to commaSeparatedList, called
delimitedList.  delimitedList is a method that gives you more control
over the elements 

Re: Boost Problem! Boost.Build not found

[Rob Wolfe]

Soren wrote:

> > Try to create boost-build.jam file like this:
> >
> > # boost-build.jam
> > boost-build C:\boost\boost_1_33_1\tools\build\v1 ;
>
>
> Hi Rob, Thanks for the answer!
>
> It did solve the error.. but produced a new one:
>
> C:\boost\boost_1_33_1\libs\python\example\tutorial>bjam -sTOOLS=vc-8_0
> Unable to load Boost.Build: could not find build system.
> -
> C:\boost\boost_1_33_1\libs\python\example\boost-build.jam attempted to
> load the
> build system by invoking
>
>'boost-build C:/boost/boost_1_33_1/tools/build/v1 ;'
>
> but we were unable to find "bootstrap.jam" in the specified directory
> or in BOOST_BUILD_PATH (searching C:\boost\boost_1_33_1, C:/boost/
> boost_1_33_1/t
> ools/build/v1).

There is something wrong with your boost installation.
Do you have subdirectory tools/build/v1 in your installation?

>
> What is bootstrap.jam? .. Haven't seen that one in the short
> tutorial...

It is essential for boost build system that the file bootstrap.jam
could be found.

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Rob

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Re: How to tell whetehr Python script called as CGI or from command line?

[Steve Holden]

[EMAIL PROTECTED] wrote:
> I'm writing a Python script that can either be called as a Cron job or
> as a web page (i.e. as a CGI in response to an HTTP request). This is
> to process the mailboxes on my web server (to which I don't have
> command line access) to remove old messages. How do I find out whether
> the script has been called as a Cron job or as a CGI? I need to know
> this so I can format the output correctly, e.g. if this is a web
> request I need to start the output with "Content-type: text/html\n
> \n", to do newlines by "" or "" etc.
> 
> Can I just access some header line which will always have a value in a
> web request, but which will be None if running from the command line
> or as a Cron job, or something similar? How?
> 
> Thanks - Rowan
> 
The CGI standard requires that the calling server sets several 
environment variables, so you could test for the presence of one or more 
of those - this is only going to be indicative, though, since any shell 
could have the same variables set in its environment.

import os
if "QUERY_STRING" in os.environ:
 # CGI script

might work.

regards
  Steve
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Re: string methods of a str subclass

[Daniel Nogradi]

> > Why is the strip( ) method returning something that is not a mystr
> > instance? I would expect all methods operating on a string instance
> > and returning another string instance to correctly operate on a mystr
> > instance and return a mystr instance.
>
> Why would you expect that?
> Would you expect the __str__ and__repr__ methods also to return a mystr
> instance? If not those, then which other ones might also be excluded?
> Is x.encode('zip') still a mystr instance or an encoded byte-string?

Okay, good point, thanks.

> > How would I achieve something
> > like this without manually copying all string returning methods from
> > str and stuffing the result to mystr( ) before returning?
>
> You don't without wrapping all the affected methods. It doesn't need to
> involve manual copying though: you have a programming language available so
> just write a list of method names and then some code to wrap them
> automatically.

Yes, this is in fact what I am doing, using __getattr__ and such. Thanks again.
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Re: Python editor/IDE on Linux?

[Paddy]

On Apr 16, 2:17 am, "Daniel Gee" <[EMAIL PROTECTED]> wrote:
> didn't know that one. Perhaps I'll look into Gvim (I still like to cut
> and paste with the mouse, even if I left that off my list).


In gvim you can use a mouse-1-drag to select text then mouse-2 at the
position you want to copy the text to.

- Paddy.

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Re: pyparsing Catch-22

[Paul McGuire]

On Apr 16, 7:25 am, "Paul McGuire" <[EMAIL PROTECTED]> wrote:
>
> long-windedness snipped

Oh, P.S., There is a list parser example included in the pyparsing
examples directory, called parsePythonValue.py.  It will parse nested
lists, dicts, and tuples.

-- Paul

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Re: Boost Problem! Boost.Build not found

[Soren]

On 16 Apr., 14:28, "Rob Wolfe" <[EMAIL PROTECTED]> wrote:
> Soren wrote:
> > > Try to create boost-build.jam file like this:
>
> > > # boost-build.jam
> > > boost-build C:\boost\boost_1_33_1\tools\build\v1 ;
>
> > Hi Rob, Thanks for the answer!
>
> > It did solve the error.. but produced a new one:
>
> > C:\boost\boost_1_33_1\libs\python\example\tutorial>bjam -sTOOLS=vc-8_0
> > Unable to load Boost.Build: could not find build system.
> > -
> > C:\boost\boost_1_33_1\libs\python\example\boost-build.jam attempted to
> > load the
> > build system by invoking
>
> >'boost-build C:/boost/boost_1_33_1/tools/build/v1 ;'
>
> > but we were unable to find "bootstrap.jam" in the specified directory
> > or in BOOST_BUILD_PATH (searching C:\boost\boost_1_33_1, C:/boost/
> > boost_1_33_1/t
> > ools/build/v1).
>
> There is something wrong with your boost installation.
> Do you have subdirectory tools/build/v1 in your installation?
>
>
>
> > What is bootstrap.jam? .. Haven't seen that one in the short
> > tutorial...
>
> It is essential for boost build system that the file bootstrap.jam
> could be found.
>
> --
> HTH,
> Rob

Hmm, I see I forgot to install boost-build .. all i did was install
boost_1_33_1.exe.. thought it had it all. Now I have unzipped   boost-
build-2.0-m11.zip inside my boost_1_33_1 directory. It contains a
bootstrap.jam file

and a new error appear:

C:\boost_1_33_1\libs\python\example\tutorial>bjam sTOOLS=vc-8_0

error: Could not find parent for project at '../../../..'
error: Did not find Jamfile or project-root.jam in any parent
directory.

In case you didn't guess... I am totally lost by now! :) If I ever get
this thing up and running.. I will write a new tutorial and send it to
boost.

Thanks!
Soren


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Re: Boost Problem! Boost.Build not found

[Soren]

On 16 Apr., 14:28, "Rob Wolfe" <[EMAIL PROTECTED]> wrote:
> Soren wrote:
> > > Try to create boost-build.jam file like this:
>
> > > # boost-build.jam
> > > boost-build C:\boost\boost_1_33_1\tools\build\v1 ;
>
> > Hi Rob, Thanks for the answer!
>
> > It did solve the error.. but produced a new one:
>
> > C:\boost\boost_1_33_1\libs\python\example\tutorial>bjam -sTOOLS=vc-8_0
> > Unable to load Boost.Build: could not find build system.
> > -
> > C:\boost\boost_1_33_1\libs\python\example\boost-build.jam attempted to
> > load the
> > build system by invoking
>
> >'boost-build C:/boost/boost_1_33_1/tools/build/v1 ;'
>
> > but we were unable to find "bootstrap.jam" in the specified directory
> > or in BOOST_BUILD_PATH (searching C:\boost\boost_1_33_1, C:/boost/
> > boost_1_33_1/t
> > ools/build/v1).
>
> There is something wrong with your boost installation.
> Do you have subdirectory tools/build/v1 in your installation?
>
>
>
> > What is bootstrap.jam? .. Haven't seen that one in the short
> > tutorial...
>
> It is essential for boost build system that the file bootstrap.jam
> could be found.
>
> --
> HTH,
> Rob

Hi Rob! Thanks for the help!

It turned out the installation had not installed all files... .. but
gave no error!!?? .. anyway, I redownloaded and installed and now it
works! Wouldn't have guessed it if you haven't said the installation
was corrupt. thanks!

Cheers,
Soren


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Writing Log CSV (Efficiently)

[Robert Rawlins - Think Blue]

Hello Guys,

 

I'm looking to write a Log file which will be CSV based, and there is a good
possibility that it'll get quite busy once its up and running, so I'm
looking for the most efficient way to achieve it. Whilst I'm sure i could do
something like this.

 

  myfile = open("Logs/Application.txt", "w")

  myfile.write('col1, col2, col3, col4, col5')

  myfile.close

 

But I'm a little apprehensive that open() and close() on a very regular
basis is just going to cause issues. I'm also a little worried that we'll
end up with 'race' type conditions and things going missing.

 

So my next thought was to just have an open object for the file, and then
perform multiple rights, until I need to send the report file somewhere
else, at which point I would close it. This in itself causes more issues as
we're running in a buffer which is just going to eat my memory, and as this
is on an embedded system which may lose power, we'd be kissing good bye to
all the logs until that point.

 

What would you guys suggest to be the most efficient way to handle this?

 

Thanks,

 

Rob

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Re: yield, curry, mix-in, new.function, global, closure, .... what will work?

[ecir . hana]

On Apr 16, 3:05 am, Paul Rubin  wrote:
> [EMAIL PROTECTED] writes:
>
> > Please, can you elaborate further, I'm not sure if I understood.
> > Should I lock global variables i, j during the execution of run()? In
> > that case I have to apologize, I showed rather simplified version of
> > the actual problem I have - in fact changer() and run() will be a bit
> > more complex thus executing a bit longer and perhaps causing a dead-lock.
>
> Put both variables into one shared object with a lock (see the docs for
> threading.RLock()).  Acquire the lock before modifying or reading the
> variables, and release it afterwards.  That is the traditional way.

Thanks for the reply! And at the same time, please bear with me.

If I understand correctly: when one thread acquires the lock, every
other thread has to wait. If so, this is not exacly what I would like
to have since the thread might take a bit longer to finish.

The reason why I try so hard to use local variables is that they are
inherently thread-safe. So I don't even mind to copy changer() every
time run() is called - run() has it's own local variables i, j, no one
has to touch them except it's ("local") function changer(). But the
problem is, I don't know how to propagate run()'s variables into
changer() without declarating them as changer()'s arguments (it would
be ok to append the declaration during run-time, though, if I only
knew how).

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Re: newbie question: how to read back the dictionary from a file?

[Fuzzyman]

On Apr 16, 11:03 am, "lancered" <[EMAIL PROTECTED]> wrote:
> Hi Dear all,
>
> I have some data here in the form of a dictionary, called "vdic". Then
> I write them to a data file "f" using   the write function as
> f.write(str(vdic)).  The keys of this dictionary are integers and
> values are float numbers. Something like this:
>
> { 1: 0.00951486513347, 2: 0.0388123556019, ... ...}
>
> Now, I want to read these data back in another function.  Of course, I
> could parse the string little by little, e.g, first read a "{", then
> loop read a int, then read a ":", then a float etc etc... Since it is
> written out with standard python builtin functions,  I guess there may
> be some more direct method than this, say a function in some modules?
> Could someone give me a hint?


ConfigObj and its 'unrepr' mode gives you a useful (and simple) way of
preserving and restoring basic Python datatypes.

The file format is a very readable 'ini' format - and the basic
interface is like a dictionary, for both writing and retrieving
values.

http://www.voidspace.org.uk/python/configobj.html

Fuzzyman

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More newbie help required with dictionaries

[loial]

The following code only returns the last row(22) added to the
machines dictionary.
presumably I need some additional syntax to add rows to the dictionary
rather than overwrite.

What do I need to add?

machinekey = "11"

machines = { machinekey:[1,0,0,0,0,0,0,0,0,0,0,0,0] }

machinekey = "22"

machines = { machinekey:[0,1,0,0,0,0,0,0,0,0,0,0,0] }

for machine in machines.keys():
   print machine

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Re: Writing Log CSV (Efficiently)

[Tim Golden]

Robert Rawlins - Think Blue wrote:
> I'm looking to write a Log file which will be CSV based, and there is a good
> possibility that it'll get quite busy once its up and running, so I'm
> looking for the most efficient way to achieve it. 


[... snip ...]
>   myfile = open("Logs/Application.txt", "w")
> 
>   myfile.write('col1, col2, col3, col4, col5')
> 
>   myfile.close
[.. snip ...]
> But I'm a little apprehensive that open() and close() on a very regular
> basis is just going to cause issues. I'm also a little worried that we'll
> end up with 'race' type conditions and things going missing.

> So my next thought was to just have an open object for the file, and then
> perform multiple rights, until I need to send the report file somewhere
> else, at which point I would close it. This in itself causes more issues as
> we're running in a buffer which is just going to eat my memory, and as this
> is on an embedded system which may lose power, we'd be kissing good bye to
> all the logs until that point.


I'm sure you'll get this same advice from everyone on
the list, but:

1) Use the csv module which comes with Python to avoid
reinventing the wheel. (Not to do with your main question, 
but worth it anyway).

2) Don't optimize too soon. It's hard to predict what effect 
things are likely to have on performance. A *lot* depends on 
your operating system, the environment, the frequency of
updates etc. etc. One obvious factor is the whether
multiple processes are writing to the file, what the
damage would be if the process crashed and the buffer didn't 
get written /closed.

3) If you really worry about the performance, do some 
profiling / timing. It's surely not too hard
to generate a stream of csv writes comparable to your target
system (or at least proportional). Use the timeit or hotshot 
modules to see what difference the open/close makes.

TJG
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Re: Writing Log CSV (Efficiently)

[Dave Borne]

On 4/16/07, Robert Rawlins - Think Blue
<[EMAIL PROTECTED]> wrote:
> I'm looking to write a Log file which will be CSV based, and there is a good
> possibility that it'll get quite busy once its up and running, so I'm
> looking for the most efficient way to achieve it. Whilst I'm sure i could do
> something like this.

Python has built in logging support. It's pretty flexible as far as
formatting output. I can get a bit complicated to set up, but it will
handle traffic well.

more info here http://docs.python.org/lib/module-logging.html

-Dave
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Re: More newbie help required with dictionaries

[Christoph Haas]

On Mon, Apr 16, 2007 at 06:43:37AM -0700, loial wrote:
> The following code only returns the last row(22) added to the
> machines dictionary.
> presumably I need some additional syntax to add rows to the dictionary
> rather than overwrite.
> 
> What do I need to add?
> 
> machinekey = "11"
> 
> machines = { machinekey:[1,0,0,0,0,0,0,0,0,0,0,0,0] }
> 
> machinekey = "22"
> 
> machines = { machinekey:[0,1,0,0,0,0,0,0,0,0,0,0,0] }

You redefine the "machines" dictionary here. So it just contains one
entry. What you mean:

machines.update({ machinekey:[0,1,0,0,0,0,0,0,0,0,0,0,0] })

Or:

machines[machinekey] = [0,1,0,0,0,0,0,0,0,0,0,0,0]

 Christoph

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Re: Writing Log CSV (Efficiently)

[skip]

Rob> I'm looking to write a Log file which will be CSV based, and there
Rob> is a good possibility that it'll get quite busy once its up and
Rob> running, so I'm looking for the most efficient way to achieve
Rob> it.

In addition to Tim's advice, if you're worried about possible loss of data
you can set a timer to flush the file object every second or so.

myfile = open("Logs/Application.txt", "wb")   # note "b"inary mode!
writer = csv.writer(myfile)
set_a_timer(1.0, myfile.flush)
...

You didn't indicate your platform so I can't be more specific about
set_a_timer().  In my work environment we use Gtk a lot, so
gobject.timeout_add works for us.  You could also call signal.alarm on
Unixoid systems.  I'm sure there's something similar in Win32.

Skip
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Re: Writing Log CSV (Efficiently)

[skip]

Dave> Python has built in logging support. It's pretty flexible as far
Dave> as formatting output. I can get a bit complicated to set up, but
Dave> it will handle traffic well.

Really?  I've found it to be a dog in heavy logging situations.

Skip
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Re: More newbie help required with dictionaries

[loial]

machines[machinekey] = [0,1,0,0,0,0,0,0,0,0,0,0,0]

is what I needed...thanks



On 16 Apr, 15:07, Christoph Haas <[EMAIL PROTECTED]> wrote:
> On Mon, Apr 16, 2007 at 06:43:37AM -0700, loial wrote:
> > The following code only returns the last row(22) added to the
> > machines dictionary.
> > presumably I need some additional syntax to add rows to the dictionary
> > rather than overwrite.
>
> > What do I need to add?
>
> > machinekey = "11"
>
> > machines = { machinekey:[1,0,0,0,0,0,0,0,0,0,0,0,0] }
>
> > machinekey = "22"
>
> > machines = { machinekey:[0,1,0,0,0,0,0,0,0,0,0,0,0] }
>
> You redefine the "machines" dictionary here. So it just contains one
> entry. What you mean:
>
> machines.update({ machinekey:[0,1,0,0,0,0,0,0,0,0,0,0,0] })
>
> Or:
>
> machines[machinekey] = [0,1,0,0,0,0,0,0,0,0,0,0,0]
>
>  Christoph


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RE: Writing Log CSV (Efficiently)

[Robert Rawlins - Think Blue]

Hello Guys,

Thanks for the advice on this one. I'm running Debian Linux as an OS, if
that makes any major differences. That inbuilt CSV stuff looked pretty tidy,
as does the logging. I'd be keen to learn a little more about that
performance wise though.

The log at its highest rate of write may be looking at an operation a
second, I've not got much experience with this kind of thing so I'm not sure
if that's 'a lot' or not, it just seems like it at the moment. It might not
get as busy as that, I'm not sure and its difficult to simulate as this
isn't likely to be a steady flow of traffic, they'll come in big fat lumps
every now and then.

Thanks,

Rob

-Original Message-
From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] 
Sent: 16 April 2007 15:12
To: Dave Borne
Cc: Robert Rawlins - Think Blue; python-list@python.org
Subject: Re: Writing Log CSV (Efficiently)


Dave> Python has built in logging support. It's pretty flexible as far
Dave> as formatting output. I can get a bit complicated to set up, but
Dave> it will handle traffic well.

Really?  I've found it to be a dog in heavy logging situations.

Skip

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Re: Writing Log CSV (Efficiently)

[Dave Borne]

On 4/16/07, [EMAIL PROTECTED] <[EMAIL PROTECTED]> wrote:
>
> Dave> Python has built in logging support. It's pretty flexible as far
> Dave> as formatting output. I can get a bit complicated to set up, but
> Dave> it will handle traffic well.
>
> Really?  I've found it to be a dog in heavy logging situations.
>
> Skip

Well I've never flogged the logging system very hard, so listen to
Skip here if you're concerned about performance.

I also don't think logging will integrate easily with the built in csv
module.  There's always ','.join(column_list)...

-Dave
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Re: Writing Log CSV (Efficiently)

[Tim Golden]

Robert Rawlins - Think Blue wrote:
> The log at its highest rate of write may be looking at an operation a
> second

I think I can probably type stuff in faster than that if
I try :) You probably don't have a performance issue there.

, I've not got much experience with this kind of thing so 
I'm not sure
> if that's 'a lot' or not, it just seems like it at the moment. It might not
> get as busy as that, I'm not sure and its difficult to simulate as this
> isn't likely to be a steady flow of traffic, they'll come in big fat lumps
> every now and then.

Sounds like you don't really need to profile that, but if
you did, Python's a great language for knocking together
that kind of test harness; combine the time, random and
csv modules and you've got a "big fat lumps every now and
then" simulation. (At which point I get jumped on by the
serious model types for being so blase with their discipline!)

TJG
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Re: Python Feature Request: Add the "using" keyword which works like "with" in Visual Basic

[Colin J. Williams]

James Stroud wrote:
> [EMAIL PROTECTED] wrote:
>> Please check for sanity and approve for posting at python-dev.
>>
>> In Visual Basic there is the keyword "with" which allows an object-
>> name to be declared as governing the following statements. For
>> example:
>>
>> with quitCommandButton
>>  .enabled = true
>>  .default = true
>> end with
>>
>> This is syntactic sugar for:
>>
>> quitCommandButton.enabled=true
>> quitCommandButton.default=true
>>
>> This can be very useful especially in GUI programming when we have to
>> type the same object name in line-after-line. I personally found
>> having to type the word "self" umpteen times inside classes very
>> irritating. Such a beautiful language is Python, she should have this
>> good feature from VB too.
>>
>> Now I hear that the word "with" is being discussed for a different
>> purpose in Py 3 as a result of a PEP and I don't want to conflict with
>> that. So I propose the word "using" as a replacement. This also is
>> similar to the C++ "using" keyword which exposes the members of a
>> namespace to access without specifying the namespace scope for each
>> reference. For example after giving "using namespace std;" I can
>> change all references to "std::cout" to "cout", which is similar to
>> what I am proposing for Python now.
>>
>> Some thoughts about how this "using" statement should behave. The word
>> using should be followed by an object name and a colon indicating the
>> start of a block. The object named after "using" must determine the
>> context (or whatever the technical word is) of the of the statements
>> in that block.
>>
>> self.setFixedSize(200, 120)
>> self.quit = QtGui.QPushButton("Quit", self)
>> self.quit.setGeometry(62, 40, 75, 30)
>> self.quit.setFont(QtGui.QFont("Times", 18, QtGui.QFont.Bold))
>> self.connect(self.quit, QtCore.SIGNAL("clicked()"), QtGui.qApp,
>> QtCore.SLOT("quit()"))
>>
>> to be rewritten as:
>>
>> using self:
>> __setFixedSize(200,120)
>> __quit = QtGui.QPushButton("Quit", self)
>> __using quit:
>> setGeometry(62, 40, 75, 30)
>> setFont(QtGui.QFont("Times", 18, QtGui.QFont.Bold))
>> __connect(self.quit, QtCore.SIGNAL("clicked()"), QtGui.qApp,
>> QtCore.SLOT("quit()"))
>>
>> [I don't know whether usenet will retain my indenting, so I changed
>> the tabs to underscores.]
>>
>> This context governing may need to be limited to the first applicable
>> member - so that in the above example "self" governs setFixedSize,
>> quit, quit and connect only in each sentence and quit (self.quit)
>> governs setGeometry and setFont only. (Point is that the parser should
>> not search for self.QtGui, self.self or self.QtCore in sentences 3 and
>> 7, and self.quit.QtGui in sentence 6.)
>>
>> Due to my absence of professional experience, my request may be
>> somewhat unpolished technical-wise, but I believe that this is a very
>> useful feature for Python and hence request the technically-
>> knowledgeable to reformat it as necessary. Thank you.
>>
> 
> I like this one for some reason. Just the "using self" would save hella 
> typing in a lot of classes. I would favor a convention with leading dots 
> to disambiguate from other variables. This wouldn't conflict with, say, 
> floats, because variable names can't begin with a number.
> 
> James

Yes, I like the idea too.  It has deeper roots than Visual Basic.  In 
Pascal, Nicklaus Wirth used "with" for record access.

It's an idea that can be used with any object which has attributes. 
The value of an attribute could be a function or a class.

It's a pity that the word "with" was used for a context declaration - 
PEP 343.  On the other hand, I believe "using" has been suggested as 
an alternative, that seems a reasonable alternative.

Colin W.

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Re: newbie question: how to read back the dictionary from a file?

[Alex Martelli]

lancered <[EMAIL PROTECTED]> wrote:

> Hi Dear all,
> 
> I have some data here in the form of a dictionary, called "vdic". Then
> I write them to a data file "f" using   the write function as
> f.write(str(vdic)).  The keys of this dictionary are integers and
> values are float numbers. Something like this:
> 
> { 1: 0.00951486513347, 2: 0.0388123556019, ... ...}
> 
> Now, I want to read these data back in another function.  Of course, I
> could parse the string little by little, e.g, first read a "{", then
> loop read a int, then read a ":", then a float etc etc... Since it is
> written out with standard python builtin functions,  I guess there may
> be some more direct method than this, say a function in some modules?
> Could someone give me a hint?

Others have suggested better ways of writing the file out.  However,
it's possible to recover the data from the string form you've written,
via the eval builtin function -- with all sorts of caveats (won't be as
fast as other approaches, enormous security risk if anybody could have
tampered with the file, etc).

To mitigate the security risks a little, try

eval(thestr, dict(__builtins__={}))

or more advanced approaches such as discussed at
,

etc.


Alex
 
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RE: Writing Log CSV (Efficiently)

[Robert Rawlins - Think Blue]

Thanks for that Tim,

I could use a little more help with this CSV stuff this afternoon and I
can't get it to write the output I want for the life of me. I'm trying to
write a method for my logging class that receives a string as an argument,
and then writes a row to the CSV with the string and a date/time stamp.

''' Add Application Log Entry '''
def addApp(self, event):
writer = csv.writer(open("some.csv", "a"))
writer.writerow(event)

Now if I do something like this; addApp('Application Started') then it
writes to the CSV file somthing like.

A,p,p,l,i,c,a,t,i,o,n, ,S,t,a,r,t,e,d

Which isn't much use to me :-D any ideas how I can get something like this:

2007-01-01,13:00:00,Application Started

Thanks,

Rob
-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED]
On Behalf Of Tim Golden
Sent: 16 April 2007 15:28
Cc: python-list@python.org
Subject: Re: Writing Log CSV (Efficiently)

Robert Rawlins - Think Blue wrote:
> The log at its highest rate of write may be looking at an operation a
> second

I think I can probably type stuff in faster than that if
I try :) You probably don't have a performance issue there.

, I've not got much experience with this kind of thing so 
I'm not sure
> if that's 'a lot' or not, it just seems like it at the moment. It might
not
> get as busy as that, I'm not sure and its difficult to simulate as this
> isn't likely to be a steady flow of traffic, they'll come in big fat lumps
> every now and then.

Sounds like you don't really need to profile that, but if
you did, Python's a great language for knocking together
that kind of test harness; combine the time, random and
csv modules and you've got a "big fat lumps every now and
then" simulation. (At which point I get jumped on by the
serious model types for being so blase with their discipline!)

TJG
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Re: OverflowError: mktime argument out of range ???

[Paul Boddie]

John Machin wrote:
>
> Maybe it does. It sure would be nice to get a definite answer. Pity
> nobody documented the time module.

"The epoch is the point where the time starts. On January 1st of that
year, at 0 hours, the ``time since the epoch'' is zero. For Unix, the
epoch is 1970. To find out what the epoch is, look at gmtime(0)."

"The functions in this module do not handle dates and times before the
epoch or far in the future."

http://docs.python.org/lib/module-time.html

> >  >>> import time
> >  >>> time.mktime((1928, 12,28, 0, 0, 0,  0, 0, 0))
> > -1294164000.0

I think the consensus is that you're lucky if your system (the C
library, more specifically) lets you play with negative time values.
Here, the inquirer happens to be playing with negative time values
(under the time module's API) and should therefore consider using the
datetime module instead.

Paul

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Re: Writing Log CSV (Efficiently)

[Tim Golden]

Robert Rawlins - Think Blue wrote:
> Thanks for that Tim,
> 
> I could use a little more help with this CSV stuff this afternoon and I
> can't get it to write the output I want for the life of me. I'm trying to
> write a method for my logging class that receives a string as an argument,
> and then writes a row to the CSV with the string and a date/time stamp.
> 
>   ''' Add Application Log Entry '''
>   def addApp(self, event):
>   writer = csv.writer(open("some.csv", "a"))
>   writer.writerow(event)
> 
> Now if I do something like this; addApp('Application Started') then it
> writes to the CSV file somthing like.
> 
> A,p,p,l,i,c,a,t,i,o,n, ,S,t,a,r,t,e,d
> 
> Which isn't much use to me :-D any ideas how I can get something like this:
> 
> 2007-01-01,13:00:00,Application Started

The writer.writerow method expects an iterable of some
sort. Usually you give it a list or a tuple (perhaps of
length one). You've given it a string, which it can happily 
iterate over. Try:

for c in "Application Started":
   print c

If you just want to print the string, pass it in as the
only element of a list or tuple:

writer.writerow ([event])

If you want to add a timestamp or whatever, then make a
list/tuple of both. (Tries to avoid restarting The Great
Tuple War (tm)):

import datetime
.
.
.
now = datetime.datetime.now ()
writer.writerow ([event, str (now)])

TJG
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How to better pickle an extension type

[dgdev]

I would like to pickle an extension type (written in pyrex).  I have
it working thus far by defining three methods:

class C:
# for pickling
__getstate__(self):
... # make 'state_obj'
return state_obj

__reduce__(self):
return C,(args,to,__init__),me.__getstate__()

# for unpickling
__setstate__(self,state_obj):
self.x=state_obj.x
...


This gets the class pickling and unpickling.

However, I'd like to not specify arguments for __init__ (as I do now
in __reduce__), and so not have __init__ invoked during unpickling.

I would like to have the pickling machinery somehow create an
uninitialized object, and then call its __setstate__, where I can re-
create it from 'state_obj'.

Is there a kosher way to do so, that is without me having to have a
special mode in the constructor for when the object is being created
by the unpickler?

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Python and SSL

[billiejoex]

Hi,
I developed an ftp-server library and now I would like to add support
for SSL/TLS as described in RFC 2228: http://tools.ietf.org/html/rfc2228
Currenlty I'm searching for documentation about this subject and I
would like to start to ask some questions:

- I noticed that socket module provides an SSL class (socket.ssl) but
even if documentation reports that it does not do any certificate
verification a lot of stdlib modules (imaplib, poplib, smtplib,
httplib and urllib2) provides SSL extension classes wherein socket.ssl
is used. What does it mean?

- On top of that why such extension classes [examples: 1, 2, 3]
accepts key-files and cert-files as optional argouments if no
certificate verification occurs?
[1] poplib.POP3_SSL( host[, port[, keyfile[, certfile]]])
[2] imaplib.IMAP4_SSL( [host[, port[, keyfile[, certfile)
[3] smtplib.starttls( [keyfile[, certfile]])

- By searching through the web I found some daemons supporting SSL
such as this one:
http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/442473
By looking at the code I notice that pyopenssl package is used and
that a certificate file is required. Why do I need to use pyopenssl
and how do I generate the cert file?

Could someone point me in the right direction?

Thanks in advance.

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Re: yield, curry, mix-in, new.function, global, closure, .... what will work?

[Jason]

On Apr 16, 7:28 am, [EMAIL PROTECTED] wrote:
> On Apr 16, 3:05 am, Paul Rubin  wrote:
>
> > [EMAIL PROTECTED] writes:
>
> > > Please, can you elaborate further, I'm not sure if I understood.
> > > Should I lock global variables i, j during the execution of run()? In
> > > that case I have to apologize, I showed rather simplified version of
> > > the actual problem I have - in fact changer() and run() will be a bit
> > > more complex thus executing a bit longer and perhaps causing a dead-lock.
>
> > Put both variables into one shared object with a lock (see the docs for
> > threading.RLock()).  Acquire the lock before modifying or reading the
> > variables, and release it afterwards.  That is the traditional way.
>
> Thanks for the reply! And at the same time, please bear with me.
>
> If I understand correctly: when one thread acquires the lock, every
> other thread has to wait. If so, this is not exacly what I would like
> to have since the thread might take a bit longer to finish.
>
> The reason why I try so hard to use local variables is that they are
> inherently thread-safe. So I don't even mind to copy changer() every
> time run() is called - run() has it's own local variables i, j, no one
> has to touch them except it's ("local") function changer(). But the
> problem is, I don't know how to propagate run()'s variables into
> changer() without declarating them as changer()'s arguments (it would
> be ok to append the declaration during run-time, though, if I only
> knew how).

In Python, names are bound to objects.  The parameter names passed to
a function *are not inherently thread safe*!  Python parameters are
not passed-by-value.  To show you what I mean:

>>> spam = ["delicious"]
>>> def test(meal):
...  global spam
...  if spam is meal:
...print "Spam is the same object as meal"
...
>>> test(spam)
Spam is the same object as meal

(While the "global spam" statement is optional in this case, I wanted
to make it painfully obvious where the "spam" name in function test is
coming from.)

It is thread-safe to rebind the name "meal" in the function test (ie,
meal = "Green eggs").   It is not thread-safe to mutate or modify the
object that meal is bound to.  In the example given above, appending
data to the list, removing data, changing elements, and other
operations will cause potential race conditions across multiple
threads.

Follow Paul's advice and get acquainted with the issues of concurrent
and threaded programming.  Judicious locking will help avoid most race
conditions.  If you don't want to keep other threads waiting, make a
copy of your data then release the data lock.

Depending on the data, you can usually have multiple threads "reading"
the data, as long as no other threads write to the data while there
are any readers.  A writer can be allowed to change the data, but only
if there are no readers and no other writers.  (This is commonly known
as a read/write lock.)  I didn't see a read/write lock in the Python
documentation with some casual browsing, but one can be implemented
from the existing thread locking mechanisms.

Your description of what you want to do is rather vague, so I can't
get too specific.  You've described how you want to do things, but I
don't know what you're trying to accomplish.  Where possible, simplify
your design.

--Jason

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win32 register

[Attila Szabo]

Hi,

I'm a unix programmer and I have minimal ideas, how things work under windows.
I have a tkinter stuff, that has to accept data from explorer,
I've done it via pipes, because I guess no drag'n'drop method exists...
At program launch, it registers a context menu handler to png files, that sends 
the drag'n'drop 
info to the program via the pipes, it is working good under administrator
privileges, but not with normal user...
The pipe server runs in a separate thread in the tkinter program...
At the end, it unregisters the menu handler...
How can a make it work with a normal user ?
I've registered the handler, but can't see in the menu under user...
Can I register the handler under admin, and run the pipe server under
user ?

thanks very much

Atti


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file resume

[luca72]

Hello at all:
if i have one file written in binary mode, how can i append others
binary data to this file after the its closure.
ex
my_file = open('blabal', 'wb')
then i write something and then
my_file.close()
now if i need to open it again and append other binary data how can i
proceed?


Regards

Luca

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RE: file resume

[Robert Rawlins - Think Blue]

Do the same again, but change that 'wb' to 'a' for append :-D should sort
you out.

Rob

-Original Message-
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED]
On Behalf Of luca72
Sent: 16 April 2007 16:57
To: python-list@python.org
Subject: file resume

Hello at all:
if i have one file written in binary mode, how can i append others
binary data to this file after the its closure.
ex
my_file = open('blabal', 'wb')
then i write something and then
my_file.close()
now if i need to open it again and append other binary data how can i
proceed?


Regards

Luca

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Re: file resume

[Marc 'BlackJack' Rintsch]

In <[EMAIL PROTECTED]>, luca72 wrote:

> if i have one file written in binary mode, how can i append others
> binary data to this file after the its closure.
> ex
> my_file = open('blabal', 'wb')
> then i write something and then
> my_file.close()
> now if i need to open it again and append other binary data how can i
> proceed?

Just open it in append mode: ``open('blablal', 'ab')``

Ciao,
Marc 'BlackJack' Rintsch
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Lame wrapper for Python

[Harlin Seritt]

Is there any type of lame_enc.dll wrapper for Python that's available?

Thanks,

Harlin Seritt

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Re: Python Feature Request: Add the "using" keyword which works like "with" in Visual Basic

[Paul Boddie]

[EMAIL PROTECTED] wrote:
> Please check for sanity and approve for posting at python-dev.

Technically, you can post it yourself to python-dev, but you'll just
get bounced back here to discuss it with us. ;-)

> In Visual Basic there is the keyword "with" which allows an object-
> name to be declared as governing the following statements. For
> example:
>
> with quitCommandButton
>  .enabled = true
>  .default = true
> end with

This is how the discussion started for the current "with" statement,
although it ended up doing something somewhat different.

[...]

> Now I hear that the word "with" is being discussed for a different
> purpose in Py 3 as a result of a PEP and I don't want to conflict with
> that.

The "with" keyword appears in 2.5 onwards.

Paul

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Re: Python and SSL

[kyosohma]

On Apr 16, 10:24 am, "billiejoex" <[EMAIL PROTECTED]> wrote:
> Hi,
> I developed an ftp-server library and now I would like to add support
> for SSL/TLS as described in RFC 2228:http://tools.ietf.org/html/rfc2228
> Currenlty I'm searching for documentation about this subject and I
> would like to start to ask some questions:
>
> - I noticed that socket module provides an SSL class (socket.ssl) but
> even if documentation reports that it does not do any certificate
> verification a lot of stdlib modules (imaplib, poplib, smtplib,
> httplib and urllib2) provides SSL extension classes wherein socket.ssl
> is used. What does it mean?
>
> - On top of that why such extension classes [examples: 1, 2, 3]
> accepts key-files and cert-files as optional argouments if no
> certificate verification occurs?
> [1] poplib.POP3_SSL( host[, port[, keyfile[, certfile]]])
> [2] imaplib.IMAP4_SSL( [host[, port[, keyfile[, certfile)
> [3] smtplib.starttls( [keyfile[, certfile]])
>
> - By searching through the web I found some daemons supporting SSL
> such as this 
> one:http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/442473
> By looking at the code I notice that pyopenssl package is used and
> that a certificate file is required. Why do I need to use pyopenssl
> and how do I generate the cert file?
>
> Could someone point me in the right direction?
>
> Thanks in advance.

I don't know if this will help you or not, but we use the httplib
module's "HTTPSConnection" method to connect with SSL. We use
urlencode from the urllib module to encode the username and password
we send to a server. Since I didn't write this particular bit of code,
I don't completely understand it. But I hope it will give you some
ideas.

Mike

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moving multiple directories

[DataSmash]

Hi,
I need to organize thousands of directories full of files.
I want to move these directories into other subdirectories.
For example, all the directories that start with 01, move to
a directory named "one", all directories that start with 02, move
to a directory name "two", and so on

I can't seem to find any easy way to do this.
Looks like shutil.move only lets you move if the subdirectory DOES
NOT exist, so after the first directory moves, the script blows up on
the second move.
I guess you could use shutil.copy or shutil.copytree but then you have
to
delete as well.  Much longer process when you have hundreds of
gigabytes of data.

Thanks for your help!
R.D.

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Re: Lame wrapper for Python

[kyosohma]

On Apr 16, 11:04 am, "Harlin Seritt" <[EMAIL PROTECTED]> wrote:
> Is there any type of lame_enc.dll wrapper for Python that's available?
>
> Thanks,
>
> Harlin Seritt

If you are talking about the LAME codec, then you might be able to use
py-lame:

http://sourceforge.net/project/showfiles.php?group_id=290&release_id=122796

And here's a post that looks like it may be related:

http://mail.python.org/pipermail/tutor/2004-January/027379.html

Mike

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script for seconds in given month?

[edfialk]

Hi, does anyone happen to know of a script that would return the
number of seconds in a month if I give it a month and a year?

My python is a little weak, but if anyone could offer some suggestions
I think I could handle it myself, or if anyone happens to know of a
script already written that performs this I would be extremely
grateful.

Thanks!
-Ed

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Re: Authenticating clients and servers

[Goldfish]

On Apr 15, 2:40 pm, Chaz Ginger <[EMAIL PROTECTED]> wrote:
> Thomas Krüger wrote:
> > Chaz Ginger schrieb:
> >> I am writing a distributed server system using Python. I need to support
> >> authentication and was wondering what approaches are available under
> >> Python and what are the best practices.

Spring Python has a section concerning Application Security you may be
interested in. (http://springpython.python-hosting.com/wiki/
ApplicationSecurity). This offers the ability to authenticate users,
but also manage what functions they can execute based on granted roles
through aspect oriented programming.

Right now, the current release supports flat-file user systems, but
the next release will also include database user stores. There are
future plans to integrate with other user stores like LDAP and so
forth.

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Python + ogr module?

[Szkandera . Karel]

Hi,
I need to do web service, which will be convert vector formats, like shapefile, 
dgn, mapinfo..(and other formats, which are supported in gdal - ogr2ogr). I 
want to do it with using ogr2ogr in the ogr python module, but i am newbie in 
python, so here is my questions. Is here anybody, who wrote any similar scripts 
and can give it me? If not, can at least anyone point me to few examples of 
using ogr2ogr in the ogr
python module?

Thank you for every answer, K.Szkandera
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C++ extension problem

[pythoncurious]

Hi,

I'm having a bit of trouble when writing a python extension. I can't
seem to figure out what I did wrong.
I tried to make a minimal example, but it's still quite a bit of
code.
It would be very appreciated if anyone could tell me what I've done
wrong.

First a short description of what I've done. The extension just wraps
a string and the class in it will just hold the string data. A 'get'
method is suppsed to just return the string value.
There's a python part that will call C/C++ functions in the
extension.
I've tried using the same approach SWIG has, so the class in the
extension doesn't really have any methods,
it's all done in methods in the module.

This is what it looks like when I try it out (also tried with
different python version and compiler):
% python
Python 2.4.3 (#1, Aug  1 2006, 16:54:29)
[GCC 3.4.6] on sunos5
Type "help", "copyright", "credits" or "license" for more information.
>>> from example import StringWrapper
>>> s = StringWrapper("S")
>>> s.get()
Traceback (most recent call last):
  File "", line 1, in ?
  File "example.py", line 7, in get
def get(self): return _example.get(self._s)
TypeError: argument 1 must be SillyString, not SillyString

Now this is what confuses me: Why does it say that I have the wrong
type when it's the same type as it suggests?

setup.py file:
###
from distutils.core import setup, Extension
module1 = Extension('_example',
sources = ['_example.cc'])
setup (name = 'example',
   ext_modules = [module1])

example.py file:

#!/usr/bin/env python
import _example

class StringWrapper(object):
def __init__(self, value):
self._s = _example.new_string(value)
def get(self): return _example.get(self._s)


and finally, the c/c++ file '_example.cc':
(I need to use c++ compiler which means I couldn't use
'staticforward'
and the 'cstring is used instead of 'string.h' )

#include "Python.h"
#include 

// forward declaration
extern PyTypeObject SillyStringType;

typedef struct {
  PyObject_HEAD
  char s[21];
} SillyStringObject;

PyObject *
new_string(PyTypeObject *type, PyObject *args)
{
char *value = 0;

if (!PyArg_ParseTuple(args, "s", &value))
return NULL;
SillyStringObject *self = PyObject_NEW(SillyStringObject,
&SillyStringType);
if (self != NULL) {
strncpy(self->s, value, 20);
}
return (PyObject *)self;
}

PyObject *
get(PyTypeObject *type, PyObject *args)
{
SillyStringObject *o;

if (!PyArg_ParseTuple(args, "O!", SillyStringType, &o))
return NULL;
return (PyObject *)PyString_FromString(o->s);
}

PyMethodDef SillyStringMethods[] = {
 {"get", (PyCFunction)get, METH_VARARGS,
  ""
 },
 {"new_string", (PyCFunction)new_string, METH_VARARGS,
  ""
 },
{NULL, NULL, 0, NULL}/* Sentinel */
};

PyTypeObject SillyStringType = {
PyObject_HEAD_INIT(NULL)
0,  /* ob_size */
(char *)"SillyString",  /* tp_name */
sizeof(SillyStringObject),  /* tp_basicsize */
0,  /* tp_itemsize */
(destructor)0,  /* tp_dealloc */
(printfunc)0,   /* tp_print */
(getattrfunc)0, /* tp_getattr */
(setattrfunc)0, /* tp_setattr */
(cmpfunc)0, /* tp_compare */
(reprfunc)0,/* tp_repr */
0,  /* tp_as_number */
0,  /* tp_as_sequence */
0,  /* tp_as_mapping */
(hashfunc)0,/* tp_hash */
(ternaryfunc)0, /* tp_call */
(reprfunc)0,/* tp_str */
0,  /* tp_getattro */
0,  /* tp_setattro */
0,  /* tp_as_buffer */
Py_TPFLAGS_DEFAULT, /* tp_flags */
"SillyString class."   /* tp_doc */
};

extern "C"
{
PyMODINIT_FUNC
init_example(void)
{
PyObject* m;
SillyStringType.tp_new = PyType_GenericNew;
if (PyType_Ready(&SillyStringType) < 0)
return;
m = Py_InitModule3("_example", SillyStringMethods,
   "_example module.");
Py_INCREF(&SillyStringType);
PyModule_AddObject(m, "SillyStringObject", (PyObject
*)&SillyStringType);
}
}

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Re: tuples, index method, Python's design

[Donn Cave]

In article <[EMAIL PROTECTED]>,
 "Hendrik van Rooyen" <[EMAIL PROTECTED]> wrote:

>  "Donn Cave" <[EMAIL PROTECTED]> wrote:
> 
> > 
> > Well, yes - consider for example the "tm" tuple returned
> > from time.localtime() - it's all integers, but heterogeneous
> > as could be - tm[0] is Year, tm[1] is Month, etc., and it
> > turns out that not one of them is alike.  The point is exactly
> > that we can't discover these differences from the items itself -
> > so it isn't about Python types - but rather from the position
> > of the item in the struct/tuple.  (For the person who is about
> > to write to me that localtime() doesn't exactly return a tuple:  QED)
> 
> This is the point where the whole thing falls apart in my head and 
> I get real confused - I can't find a reason why, list or tuple, the first
> item can't be something, the second something else, etc...

Of course, you may do what you like.  Don't forget, though,
that there's no "index" method for a tuple.

   Donn Cave, [EMAIL PROTECTED]
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Re: script for seconds in given month?

[Jim]

On Apr 16, 12:22 pm, "edfialk" <[EMAIL PROTECTED]> wrote:
> Hi, does anyone happen to know of a script that would return the
> number of seconds in a month if I give it a month and a year?
>
> My python is a little weak, but if anyone could offer some suggestions
> I think I could handle it myself, or if anyone happens to know of a
> script already written that performs this I would be extremely
> grateful.
Probably there are sophisticated answers, but have you tried
something like:

monthDays={'Jan':31,'Feb':28, ..}
secs=60*60*24*monthDays[thisMonth]
if (thisMonth=='Feb'
and isLeap(thisYear)):
secs+=60*60*24
return secs

?

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Re: tuples, index method, Python's design

[Chris Mellon]

On 4/12/07, Alan Isaac <[EMAIL PROTECTED]> wrote:
> Chris Mellon said:
> > Sure. I have never done this. In fact, I have only ever written code
> > that converted a tuple to a list once, and it was because I wanted
> > pop(), not index()
>
> Well then you apparently made a *mistake*: you chose a tuple when you
> wanted a mutable object.  That is really beside the point.
>

The tuple in question was function varargs. Yes, I wanted a mutable
object, thats why I made a list out of it. Whether varargs should be a
list or a tuple to begin with is
open to debate, but it's not likely you'd want to use index() on it either way.

> And you missed the point of my query.  It is not that existing code will
> contain such a conversion to get access to the index method.  It is that
> if you choose tuples to represent immutable sequences, sooner or later
> you will find you need to change your code to use a list not because you
> really want a mutable sequence but because you want the ``index`` method.
>

That may have been your point, but it's not what you said. I've never
converted a tuple to a list because I needed index(). I've never used
a list where a tuple would be "more natural" soley because I needed to
search it, either. I have never used index() in a situation where the
sequence in question wasn't both a) mutable and b) actually was
mutated in the course of program.

> Note that it has become clear that some people do not use tuples hardly
> ever, regardless whether their sequence is naturally mutable or
> immutable.  Why?  Because they want access the the list methods.
> **All** of these people fall in the category I am talking about.
> I do not really care if you reach mentally and then fix or actually type it.
> The avoidance of tuples, so carefully defended in other terms,
> is often rooted (I claim) in habits formed from need for list methods like
> ``index`` and ``count``.  Indeed, I predict that Python tuples
> will eventually have these methods and that these same people
> will then defend *that* status quo.
>

I use tuples all the time. There are more incidences of tuple usage
than list usage in my current codebase. My opinions on tuples still
stand. I use tuples when I already know what goes into them and in
what order. index() and count() are totally useless when you use
tuples (or, indeed, any sequence) in this manner.
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Re: script for seconds in given month?

[pythoncurious]

On Apr 16, 6:22 pm, "edfialk" <[EMAIL PROTECTED]> wrote:
> Hi, does anyone happen to know of a script that would return the
> number of seconds in a month if I give it a month and a year?
>

something like this might work, it should event handle DST correctly.
You could read up on mktime() if you want to make sure.

from time import mktime
def secondsInMonth(year, month):
s1 = mktime((year,month,1,0,0,0,0,0,-1))
s2 = mktime((year,month+1,1,0,0,0,0,0,-1))
return s2-s1

/Matt

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Re: yield, curry, mix-in, new.function, global, closure, .... what will work?

[ecir . hana]

On Apr 16, 5:36 pm, "Jason" <[EMAIL PROTECTED]> wrote:
> On Apr 16, 7:28 am, [EMAIL PROTECTED] wrote:
>
>
>
> > On Apr 16, 3:05 am, Paul Rubin  wrote:
>
> > > [EMAIL PROTECTED] writes:
>
> > > > Please, can you elaborate further, I'm not sure if I understood.
> > > > Should I lock global variables i, j during the execution of run()? In
> > > > that case I have to apologize, I showed rather simplified version of
> > > > the actual problem I have - in fact changer() and run() will be a bit
> > > > more complex thus executing a bit longer and perhaps causing a 
> > > > dead-lock.
>
> > > Put both variables into one shared object with a lock (see the docs for
> > > threading.RLock()).  Acquire the lock before modifying or reading the
> > > variables, and release it afterwards.  That is the traditional way.
>
> > Thanks for the reply! And at the same time, please bear with me.
>
> > If I understand correctly: when one thread acquires the lock, every
> > other thread has to wait. If so, this is not exacly what I would like
> > to have since the thread might take a bit longer to finish.
>
> > The reason why I try so hard to use local variables is that they are
> > inherently thread-safe. So I don't even mind to copy changer() every
> > time run() is called - run() has it's own local variables i, j, no one
> > has to touch them except it's ("local") function changer(). But the
> > problem is, I don't know how to propagate run()'s variables into
> > changer() without declarating them as changer()'s arguments (it would
> > be ok to append the declaration during run-time, though, if I only
> > knew how).
>
> In Python, names are bound to objects.  The parameter names passed to
> a function *are not inherently thread safe*!  Python parameters are
> not passed-by-value.  To show you what I mean:
>
> >>> spam = ["delicious"]
> >>> def test(meal):
>
> ...  global spam
> ...  if spam is meal:
> ...print "Spam is the same object as meal"
> ...>>> test(spam)
>
> Spam is the same object as meal
>
> (While the "global spam" statement is optional in this case, I wanted
> to make it painfully obvious where the "spam" name in function test is
> coming from.)
>
> It is thread-safe to rebind the name "meal" in the function test (ie,
> meal = "Green eggs").   It is not thread-safe to mutate or modify the
> object that meal is bound to.  In the example given above, appending
> data to the list, removing data, changing elements, and other
> operations will cause potential race conditions across multiple
> threads.
>
> Follow Paul's advice and get acquainted with the issues of concurrent
> and threaded programming.  Judicious locking will help avoid most race
> conditions.  If you don't want to keep other threads waiting, make a
> copy of your data then release the data lock.
>
> Depending on the data, you can usually have multiple threads "reading"
> the data, as long as no other threads write to the data while there
> are any readers.  A writer can be allowed to change the data, but only
> if there are no readers and no other writers.  (This is commonly known
> as a read/write lock.)  I didn't see a read/write lock in the Python
> documentation with some casual browsing, but one can be implemented
> from the existing thread locking mechanisms.
>
> Your description of what you want to do is rather vague, so I can't
> get too specific.  You've described how you want to do things, but I
> don't know what you're trying to accomplish.  Where possible, simplify
> your design.
>
> --Jason

All I was trying to do, was to get rid of those 'k's in changer():



def change_i(k, arg):
k[0] = arg

def change_j(k, arg):
k[1] = arg

def changer(k):
change_i(k, 'changed_i')
change_j(k, 'changed_j')

def run(i='', j=''):
k = [i, j]
changer(k)
[i, j] = k
return i, j

print run() == ('changed_i', 'changed_j')



Maybe I made a mistake, I should have asked this first, sorry. If the
only way to accomplish this is through locks, then I guess I better
use those 'k's, what do you think?

Thanks Jason, thanks Paul!

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swig win32 scons

[myheartinamerica]

Hello,

I spent the morning figuring out how to use SWIG on Microsoft Windows.
I compiled the example from the SWIG tutorial on http://www.swig.org.
The biggest stumbling block was not knowing that I needed to rename
the DLL created to have a PYD extension. I also ended up writing
a .def file for exporting functions from the DLL.

Here is my SConstruct file for using SCons to build the library. It is
not perfect, but it should be evident as to what I was doing. I hope
that others will be able to find this in the future and save
themselves some time.:


##
SWIG_EXE = r'C:\Python25\swig\swig.exe'


env = Environment(SWIG=SWIG_EXE,
  SWIGFLAGS=['-python'],
  CPPPATH=[r'C:\Python25\include'],
  LIBPATH=[r'C:\Python25\libs'])
swigObject = env.SharedObject(['example.i'])
copyToPYD = Copy('_example.pyd', '_example.dll')
env.AddPostAction('_example.dll', copyToPYD)
env.SharedLibrary('_example.dll', ['example.c', swigObject])

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Re: script for seconds in given month?

[skip]

Matt> from time import mktime
Matt> def secondsInMonth(year, month):
Matt> s1 = mktime((year,month,1,0,0,0,0,0,-1))
Matt> s2 = mktime((year,month+1,1,0,0,0,0,0,-1))
Matt> return s2-s1

Probably won't work if month==12. ;-)

Skip
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Re: swig win32 scons

[myheartinamerica]

It turns out I didn't need the DEF file for exports.



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Re: script for seconds in given month?

[Paul McGuire]

On Apr 16, 11:22 am, "edfialk" <[EMAIL PROTECTED]> wrote:
> Hi, does anyone happen to know of a script that would return the
> number of seconds in a month if I give it a month and a year?
>
> My python is a little weak, but if anyone could offer some suggestions
> I think I could handle it myself, or if anyone happens to know of a
> script already written that performs this I would be extremely
> grateful.
>
> Thanks!
> -Ed

Do you need to handle leap seconds too? (not a joke)

-- Paul

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subprocess confusion

[Tim Arnold]

Hi,
Just discovered that my subprocess call with the preexec_fn wasn't doing 
what I thought.
If 'machine' value is different than the current machine name, I want to 
remsh the command to that machine, but obviously I misunderstood the 
preexec_fn arg.

Should I just put the remsh in the actual command instead of preexec_fn?
thanks,
--Tim Arnold
---
if machine == socket.gethostname():
shname = None
else:
shname = lambda :'/bin/remsh %s ' % (machine)
p = subprocess.Popen(preexec_fn = shname,
shell  = True,
args   = command,
stderr = subprocess.STDOUT,
stdout = log,
env= env,
)
try:
p.wait()
if log:
log.close()
except:
pass

--- 


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