Re: Derived class and deepcopy
Philip Smith wrote: In the given example I want to apply deepcopy() to the Matrix instance (on initialisation) to ensure that the list part is not affected by subsequent changes to the initialising list or Matrix but this gives me a string of errors (some of which imply I'm trying to copy the class rather than the instance). Anyone got any thoughts on this where's the example? what errors do you get? /F -- http://mail.python.org/mailman/listinfo/python-list
Re: Problem using/installing numarray
[EMAIL PROTECTED] wrote:
ImportError: No module named _conv
The file _conf.pyd exists, but my guess is that the .pyd suffix is not
recognized under the CygWin version of Python. (But that doesn't make
sense...)
you can use imp.get_suffixes() to get a list of supported extensions.
here's the output from a stock python.org stock interpreter on WinXP:
import imp
imp.get_suffixes()
[('.pyd', 'rb', 3), ('.dll', 'rb', 3), ('.py', 'U', 1), ('.pyw', 'U', 1),
('.pyc', 'rb', 2)]
/F
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Re: Why doesn't join() call str() on its arguments?
Nick Vargish wrote: Leo Breebaart [EMAIL PROTECTED] writes: That suggests to me an obvious default of the kind that exists elsewhere in Python as well. I feel pretty much the opposite... If a non-string-type has managed to get into my list-of-strings, then something has gone wrong and I would like to know about this potential problem. If you want to do force a conversion before the join, you can use a list comp: ', '.join([str(x) for x in l]) Nick Explicit is better than Implicit Really ? Then why are you using python. Python or most dynamic languages are are so great because of their common sense towards the implicit. You must have heard of never say never but never say always (as in always better) is more appropriate here. There are many cases of python's implicitness. What about a = string b = 2 c = %s%s % (a, b) There is an implicit str(b) here. ''.join([string, 2]) to me is no different then the example above. Huy -- http://mail.python.org/mailman/listinfo/python-list
Re: Why doesn't join() call str() on its arguments?
news.sydney.pipenetworks.com wrote: Nick Explicit is better than Implicit Really ? Then why are you using python. Python or most dynamic languages are are so great because of their common sense towards the implicit. You must have heard of never say never but never say always (as in always better) is more appropriate here. There are many cases of python's implicitness. a certain princess bride quote would fit here, I think. What about a = string b = 2 c = %s%s % (a, b) There is an implicit str(b) here. nope. it's explicit: %s means convert using str(). from the documentation: %s String (converts any python object using str()). ''.join([string, 2]) to me is no different then the example above. so where's the %s in your second example? /F -- http://mail.python.org/mailman/listinfo/python-list
RE: huge help for interactive python
[David S.] [... snip recommendation of Gary Bishop's readline ...] | | I could not find a list of the keyboard commands | that readline supports, so I generated: | | http://fsinnovations.net/share/keymap.pdf Brilliant! Thanks very much. I've half-used ipython for several months, but I'm so keyboard-aware in the normal Windows cmd shell that I found it a hard switch, no matter how well- motivated I was. Now I hope to make the best of both worlds. TJG This e-mail has been scanned for all viruses by Star. The service is powered by MessageLabs. For more information on a proactive anti-virus service working around the clock, around the globe, visit: http://www.star.net.uk -- http://mail.python.org/mailman/listinfo/python-list
Re: low-end persistence strategies?
On Wed, Feb 16, 2005 at 10:43:42PM -0800, Michele Simionato wrote: snip simple example with flock What happens if for any reason the application crashes? Locked files will stay locked or not? And if yes, how do I unlock them? the operating system cleans up the lock. -- John Lenton ([EMAIL PROTECTED]) -- Random fortune: Linux ext2fs has been stable for a long time, now it's time to break it -- Linuxkongreß '95 in Berlin signature.asc Description: Digital signature -- http://mail.python.org/mailman/listinfo/python-list
:-)
Jack Diederich [EMAIL PROTECTED] wrote: /tmp/ python Python 2.3.4 (#2, Jan 5 2005, 08:24:51) Type help, copyright, credits or license for more information. ^D :-) :-) :-) :-) :-) :-) :-) :-) :-) :-) :-) :-) :-) Bart -- http://mail.python.org/mailman/listinfo/python-list
Re: Help with C extensions under VC6 / WinXP and Python 2.4
Simon John wrote: What's the difference between ctypes, SWIG and SIP? I've used SWIG to convert C source to Python (as I believe SIP does?), so does ctypes wrap functions from binaries (e.g. DLL's)? ctypes is a runtime linker. it generates bindings on the fly, at runtime, and doesn't require a separate compilation step. /F -- http://mail.python.org/mailman/listinfo/python-list
Re: low-end persistence strategies?
John Lenton: the operating system cleans up the lock. So, are you effectively saying than a custom made solution based on flock can be quite reliable and it could be a reasonable choice to use shelve+flock for small/hobbysts sites? I always thought locking was a bad beast and feared to implement it myself, but maybe I was wrong afterall ... Michele Simionato -- http://mail.python.org/mailman/listinfo/python-list
Re: Help with C extensions under VC6 / WinXP and Python 2.4
Hello Simon, What's the difference between ctypes, SWIG and SIP? SIG and SIP take C/C++ *sources* and create Python modules. ctypes works directly with the binary dll. Bye. -- Miki Tebeka [EMAIL PROTECTED] http://tebeka.bizhat.com The only difference between children and adults is the price of the toys -- http://mail.python.org/mailman/listinfo/python-list
Best way to SIGHUP spamd from web page?
I'd like to be able to restart spamd (the SpamAssassin daemon) from a web page, so that it will reload its system config files. Currently, I'm only worried about Debian; my SA is from the testing (Sarge) distro, and I'm running Apache 1.3. I don't have any other signals to send, or commands, and no dynamic values other than the pid (which I can read just fine from /var/run/spamd.pid). Basically, there are half-a-dozen different ways to get this to happen, but all of them spend 3/4 of their documentation saying DON'T EVER DO THIS. I'm just wondering if anyone has recommendations for whose advice to ignore first. ;) Detailed explanations of your choice would be much appreciated, of course. Robert Brewer MIS Amor Ministries [EMAIL PROTECTED] -- http://mail.python.org/mailman/listinfo/python-list
performance increase rpm v compile
Hello, I am working on a python app which does quite a lot of database manipulation via berkeley db. An increase in performance would be welcome, although ait is pretty quick it just has a lot to do. Currently it runs on RH 8.0, FC2 or 3 coming. And it is installed from an (rpm python-2.2.1-17). It runs on a dual processor xeon. My experience with X leads me to believe you can get a performance increase of 10-20% from compiling it. Is this likely to be true for python? TIA Tony -- http://mail.python.org/mailman/listinfo/python-list
Re: [newbie]How to install python under DOS and is there any Wxpython can be installed under dos?
john san skrev: pure DOS, old pc, used for teaching . want show some windows under DOS (under Python). curses is a text-based interface that will let you build windowed applications like you could with the crt unit in Turbo Pascal of those golden days. I've no idea if anyone's compiled it for the 16-bits DOS platform, though. -- Leif Biberg Kristensen -- http://mail.python.org/mailman/listinfo/python-list
Re: [newbie]How to install python under DOS and is there any Wxpython can be installed under dos?
john san skrev: Actually the windows running very good under the xbox-NTOS via xboxmediacenter. its just limited functions(not easy to programming the windows prog.), if we can find WxPython-like can be ported (I can import * from it to my xboxPython) )it will be a great great . You will have HD screen and web surfing on HDTV and computing on HDTV. think about it! That is a real thing the python-like lang. should to do otherwise just a garbage(toy). You can run Linux with MythTV on an XBox. Does all the things you want, and of course it will run WxPython. -- Leif Biberg Kristensen -- http://mail.python.org/mailman/listinfo/python-list
RE: keeping a COM server alive
Hi, there is no real solution if you are using a standard local server. The server is as a COM object reference counted. So if the reference count reaches 0 (no client) it will shutdown itself which is done by design. If you want a different behavior you should write either a service which exports COM objects and is started by the operating system or a Python script which you start by hand, registers the class factories and then does not shut down. Stefan -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] Behalf Of [EMAIL PROTECTED] Sent: Monday, February 14, 2005 12:53 PM To: python-list@python.org Subject: keeping a COM server alive I have implemented a local COM Server with win32com framework where all clients use the same global object (test_obj). So far it works, but when the last client is closed the gobal object is deleted because the pythonw.exe is closed. When I create a new client a new pythonw process is started. I need that the new client gets the same global object. How can I prevent the Python COM enviornment (pythonw.exe) to close when no client exist. I figured out a workaround, but there must be real solution to the problem. The code looks like: class test: ... test_obj=test() class test_F: _reg_clsid_ = ... _reg_progid_ = test.cl _reg_clsctx_ = pythoncom.CLSCTX_LOCAL_SERVER _public_methods_ = ... def __init__(self): self.delegate=test_obj ... Workaround to keep the local server alive if not __name__=='__main__': import win32com.client dummy=win32com.client.Dispatch(test.cl) ## if __name__=='__main__': import win32com.server.register win32com.server.register.UseCommandLine(test_F, debug=0) -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: Pmw.Balloon under Windows
On 16 Feb 2005 10:51:27 -0800, Aki Niimura [EMAIL PROTECTED] wrote: [snip] The software is working fine under Solaris 9. However, when I tried it under Windows, it worked also fine but it spit out the following error message when exiting. (from cygwin terminal) % c:/Python23/python my_app.py This application has requested the Runtime to terminate it in an unusual way. Please contact the application's support team for more information. (the same error message is observed when I run the program directly in Windows XP environment.) // [snip] After painful investigation, I found Pmw.Balloon was causing this problem (because the problem went away if I commented out all balloon statements). Then I compared my usages and Pmw Balloon example because the example didn't cause this. (http://pmw.sourceforge.net/doc/Balloon.html) I used the Pmw.Balloon quite a lot and never see any problem. One question: what Python do you use? Is it a regular Windows Python distribution or the Python delivered with Cygwin? I know by experience that the Python in Cygwin has quite a lot of problems (mine crashes *very* often). If you don't already use a regular Windows distro, I think using one may solve your problem. My questions are: (1) Why my program is complaining and is there any workaround? (2) What is the difference between using widget quit() method and using Windows 'X' button. - I know clicking Windows 'X' button generates an event but I thought - ultimately it reached to the same routine to terminate the program. I think the default binding for the 'X' button is to call destroy, not quit. Calling destroy on the main window is almost equivalent to calling quit, so maybe it can be a solution? (3) Is it possible to fake clicking 'X' button? I see a widget has event_generate() method. Not that I know of. The event_generate method won't help here, because the 'X' button is handled by the window manager, and not by the application. It's a bit more complicated on Windows (as usual...) since there is no real window manager, but from the tk/Tkinter point of view, the result is the same: you can't fake a window manager event using event_generate. BTW, what are the versions of Python, tk and Pmw you're using? HTH a little... - Eric Brunel - -- http://mail.python.org/mailman/listinfo/python-list
Re: Stable GUI
I've used Tkinter quite extensively for various tools, but never for anything big. I believe it will work nicely for a data input type of application. I don't know if you'll experience significant lag when updating app-windows on old pentiums, but it shouldn't be a problem. Mind you, the machines should have a decent amount of ram (I guess around 128 mb and upwards is reasonable). The only problem I've ever encountered was with updating Tk widgets from threads in a threaded app - it won't work. The solution was nothing worse than using an output queue, and having an event check the output buffer every second or so. The Tcl/TK crowd probably have more extensive experience with using Tk and Tix for bigger long running apps, maybe you can ask them for more info? Good luck with your app! Lars -- http://mail.python.org/mailman/listinfo/python-list
Re: Why doesn't join() call str() on its arguments?
Nick Vargish [EMAIL PROTECTED] wrote: I feel pretty much the opposite... If a non-string-type has managed to get into my list-of-strings, then something has gone wrong and I would like to know about this potential problem. This is a good argument. Why not have another method to do this? I propose joinany which will join any type of object together, not just strings That way it becomes less of a poke in the eye to backwards compatibility too. Nick Explicit is better than Implicit Aye! -- Nick Craig-Wood [EMAIL PROTECTED] -- http://www.craig-wood.com/nick -- http://mail.python.org/mailman/listinfo/python-list
Re: Help with C extensions under VC6 / WinXP and Python 2.4
Scott wrote: I'm specifically trying to perform step 6. Creating a brand new project using VC6. The instructions are outdated. Don't use VC6 to build extension modules for Python 2.4. Regards, Martin -- http://mail.python.org/mailman/listinfo/python-list
Re: Why doesn't join() call str() on its arguments?
Nick Craig-Wood wrote: Nick Vargish [EMAIL PROTECTED] wrote: Why not have another method to do this? I propose joinany which will join any type of object together, not just strings l = [1,2,3,'four'] ','.join(map(str, l)) '1,2,3,four' Is this really that hard to do, that you want it in the library? -- hilsen/regards Max M, Denmark http://www.mxm.dk/ IT's Mad Science -- http://mail.python.org/mailman/listinfo/python-list
Re: Why doesn't join() call str() on its arguments?
Nick Craig-Wood wrote: Why not have another method to do this? I propose joinany which will join any type of object together, not just strings I think that's what Frederik was proposing. Except that it would be called join and be a built-in (not a str method). -- Michael Hoffman -- http://mail.python.org/mailman/listinfo/python-list
Re: Why doesn't join() call str() on its arguments?
Max M wrote: ','.join(map(str, l)) '1,2,3,four' Is this really that hard to do, that you want it in the library? I think it's a sufficiently common use case that having to do that is a wart. -- Michael Hoffman -- http://mail.python.org/mailman/listinfo/python-list
Re: Stable GUI
Lars napisa(a): The only problem I've ever encountered was with updating Tk widgets from threads in a threaded app - it won't work. The solution was nothing worse than using an output queue, and having an event check the output buffer every second or so. I know literally no GUI toolkit, that allows direct updating of GUI objects from any other thread that the one which created them. Some even do not allow updating from any other thread than main application thread and this may be really painful. -- Jarek Zgoda http://jpa.berlios.de/ | http://www.zgodowie.org/ -- http://mail.python.org/mailman/listinfo/python-list
Re: MYSQL - how to install ?
Daniel Bowett wrote: Lad wrote: I am sorry it was my fault I did not say that clearly. I do not have a problem to install MySQL server but I do not know how to install MySQLdb module on my windowsXP so that I can work with MySQL server via Python 2.3. Thanks for help Lad Try this installer, if you want a newer version you will need to compile it yourself. http://prdownloads.sourceforge.net/mysql-python/MySQL-python.exe-1.0.0.win32-my4.1-py2.3.exe?download Thank you I will try. As far as I understand I can install the latest MySQL server and then MySQLdb module on my windowsXP with the installer( the link you provided above). Is it so? Lad. -- http://mail.python.org/mailman/listinfo/python-list
Re: difference between class methods and instance methods
John M. Gabriele wrote: I've done some C++ and Java in the past, and have recently learned a fair amount of Python. One thing I still really don't get though is the difference between class methods and instance methods. I guess I'll try to narrow it down to a few specific questions, but any further input offered on the subject is greatly appreciated: I'll try not to cover the same ground as Steven did in his reply. 1. Are all of my class's methods supposed to take 'self' as their first arg? consider this: class Demo(object): def foo(self, x): print self, x @classmethod def clsmethod(cls, x): print cls, x @staticmethod def stmethod(x): print x instance = Demo() Calling a bound method, you don't pass an explicit self parameter, but the method receives a self parameter: bound = instance.foo bound(2) __main__.Demo object at 0x00B436B0 2 Note that it doesn't matter whether you call instance.foo(2) directly, or bind instance.foo to a variable first. Either will create a *new* bound method object, and the correct instance is used for the call. This is significantly different from languages such as C++ and Javascript which are a real pain if you want to use a method as a callback. Calling an unbound method, you pass a self parameter explicitly (and it must be an instance of the class, *or an instance of a subclass*: unbound = Demo.foo unbound(instance, 2) __main__.Demo object at 0x00B436B0 2 Again is doesn't matter whether you do this in one step or two. The usual case for using an unbound method is when you have overridden a method in a derived class and want to pass the call on to a base class. e.g. class Derived(Demo): def foo(self, x): Demo.foo(self, x) A class method is usually called through the class rather than an instance, and it gets as its first parameter the actual class involved in the call: Demo.clsmethod(2) class '__main__.Demo' 2 Derived.clsmethod(2) class '__main__.Derived' 2 You can call a class method using an instance of the class, or of a subclass, but you still the get class passed as the first parameter rather than the instance: d = Derived d.clsmethod(2) class '__main__.Derived' 2 A common use for class methods is to write factory functions. This is because you can ensure that the object created has the same class as the parameter passed in the first argument. Alternatively you can use class methods to control state related to a specific class (e.g. to count the number of instances of that exact class which have been created.) There is no equivalent to a class method in C++. Static methods are like static methods in C++. You can call them through the class or a subclass, or through an instance, but the object used in the call is not passed through to the method: Demo.stmethod(2) 2 instance.stmethod(2) 2 Derived.stmethod(2) 2 d.stmethod(2) 2 2. Am I then supposed to call them with MyClass.foo() or instead: bar = MyClass() bar.foo() ? If you have an instance then use it. If the class method is a factory then you might want to create a new object of the same type as some existing object (but not a simple copy since you won't get any of the original object's state). Mostly though you know the type of the object you want to create rather than having an existing instance lying around. 3. Is bound method a synonym for instance method? Close but not quite. It is a (usually transient) object created from an unbound instance method for the purposes of calling the method. 4. Is unbound method a synonym for class method? Definitely not. And if anyone's *really* daring: Where do the so-called static methods fit into all this? By the name of them, it sounds like the same thing as class methods... See above. -- http://mail.python.org/mailman/listinfo/python-list
Re: Why doesn't join() call str() on its arguments?
Leo Breebaart wrote: All I've been able to find is a 1999 python-dev post by Tim Peters which would seem to indicate he doesn't understand it either: string.join(seq) doesn't currently convert seq elements to string type, and in my vision it would. At least three of us admit to mapping str across seq anyway before calling string.join, and I think it would be a nice convenience [...] But now it's 2005, and both string.join() and str.join() still explicitly expect a sequence of strings rather than a sequence of stringifiable objects. There's a more recent discussion than that, because I tried to change it shortly after I offered a patch to fix a corner case for string subclasses. This seems to be the last relevant message in the thread: http://mail.python.org/pipermail/python-dev/2004-August/048516.html So it was tried, but we found too many weird corner cases we weren't quite sure what to do with. At that point, explicit is better than implicit kicked in :) A shame, since it was both faster and more convenient than using a list comp. But the convenience wasn't worth the ambiguity of the semantics. Cheers, Nick. P.S. For anyone else that uses Firefox: Linking the pydev keyword to http://www.google.com/search?q=site:mail.python.org+inurl:python-dev+%s; and the pylist keyword to http://www.google.com/search?q=site:mail.python.org+inurl:python-list+%s; makes searching the archives on python.org really easy. Of course, knowing what you're looking for because you were a participant in the discussion helps, too ;) -- Nick Coghlan | [EMAIL PROTECTED] | Brisbane, Australia --- http://boredomandlaziness.skystorm.net -- http://mail.python.org/mailman/listinfo/python-list
Re: MYSQL - how to install ?
[EMAIL PROTECTED] wrote: Daniel Bowett wrote: Lad wrote: I am sorry it was my fault I did not say that clearly. I do not have a problem to install MySQL server but I do not know how to install MySQLdb module on my windowsXP so that I can work with MySQL server via Python 2.3. Thanks for help Lad Try this installer, if you want a newer version you will need to compile it yourself. http://prdownloads.sourceforge.net/mysql-python/MySQL-python.exe-1.0.0.win32-my4.1-py2.3.exe?download Thank you I will try. As far as I understand I can install the latest MySQL server and then MySQLdb module on my windowsXP with the installer( the link you provided above). Is it so? Lad. Thats correct. -- http://mail.python.org/mailman/listinfo/python-list
need of help
Hello, Please I need of help about : * how to display an browser window * how to display a window in the midle of the screen and finaly how to insert an image in a canvas within a program -- http://mail.python.org/mailman/listinfo/python-list
Re: MYSQL - how to install ?
Sorry about the mis-read. Keep in mind that if you're doing this on win32 (and it looks like you are), you can use ODBC a bit easier. :) -- http://mail.python.org/mailman/listinfo/python-list
Re: need of help
Need more info on this. Are you:
1. Trying to create a GUI window of your own making? If so, what
toolkit are you using?
2. Trying to open a web browser? If so, you can do the following:
import os
os.system('path/to/executable options')
or
os.startfile('pagename.html')
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Re: Pausing a program - poll/sleep/threads?
import time play_something() time.sleep(LengthOfSongInSeconds) do_something() Have you tried that? I'd be interesting in seeing this app you have. ! -- http://mail.python.org/mailman/listinfo/python-list
Re: keeping a COM server alive
Hi, thanks, I 'll post the problem in python-win32@python.org ... Frank -- http://mail.python.org/mailman/listinfo/python-list
Re: PythonCard and Py2Exe
[EMAIL PROTECTED] wrote: (Most recent call last): C:\Documents and Settings\Gateway User\ Desktop\custdb\setup.py, line 1, name = custdb, 'setup' is not defined There may be a single word infront of 'setup' on the fourth line, it scramble on my screen because I have to use a screen capture to read the error (it pops up for just a second before the window shuts down. That's because you're not running it from a command prompt. Please open a command prompt (Start Menu, select Run, type cmd.exe and ENTER, then type the following line to get to the folder with the script: cd c:\documents and settings\gateway user\desktop\custdb (If that doesn't work, perhaps there is really a space in front of desktop as you show above...) Once you're there, you should be able to run the script directly just by typing its name plus the arguments required: setup.py py2exe (without the quotes). If you can get that far, you should have the full error message in a form you can directly cut and paste. If it adds nothing over what you show above, however, then I'm at a loss because I can't see how your script could possibly have generated that error... Here's the full setup.py script I ran to get the error: from distutils.core import setup import py2exe setup( name = custdb, console = [custdb.py], data_files = [ (., [custdb.ini, custdb.de.rsrc.py custdb.rsrc.py, customerdata.csv]) ] This makes no sense to me, given the error message. The error reports that it fails on line 1, yet line 1 in the above is the import statement, and doesn't have name = custdb on it as the error reports. -Peter -- http://mail.python.org/mailman/listinfo/python-list
Re: Why doesn't join() call str() on its arguments?
Leo Breebaart wrote: What I can't find an explanation for is why str.join() doesn't automatically call str() on its arguments I don't really like that idea for the reasons others have stated. But a related and (IMHO) more Pythonic idea would be to allow arbitrary objects to be str.join()ed if they use __radd__ to allow concatenation with strings. This would be consistent with how the + operator behaves: Python 2.4 (#2, Jan 8 2005, 20:18:03) [GCC 3.3.5 (Debian 1:3.3.5-5)] on linux2 Type help, copyright, credits or license for more information. class Foo(object): ... def __radd__(self, other): ... if isinstance(other, basestring): ... return other + str(self) ... def __str__(self): ... return 'Foo()' ... 'foo:' + Foo() 'foo:Foo()' ''.join(['foo', Foo()]) Traceback (most recent call last): File stdin, line 1, in ? TypeError: sequence item 1: expected string, Foo found -- http://mail.python.org/mailman/listinfo/python-list
Help needed for to build a CGI shell interface.
I don't get it with the popen (popen3 or subprocess). 1. How do I establish my pipes? 2. And how do I interact with the pipes (interactive CGI-page)? Thanks, Dominik -- http://mail.python.org/mailman/listinfo/python-list
Re: gui scripting
hi, thanks - am already involved in a process to modify winguiauto.py - this is a GREAT start but we need more control and better handleing ;) Thanks for the WATSUP site - will check on this as well ;) Thanks T -- http://mail.python.org/mailman/listinfo/python-list
Re: [newbie]How to install python under DOS and is there any Wxpython can be installed under dos?
Leif B. Kristensen wrote: john san skrev: Actually the windows running very good under the xbox-NTOS via xboxmediacenter. its just limited functions(not easy to programming the windows prog.), if we can find WxPython-like can be ported (I can import * from it to my xboxPython) )it will be a great great . You will have HD screen and web surfing on HDTV and computing on HDTV. think about it! That is a real thing the python-like lang. should to do otherwise just a garbage(toy). You can run Linux with MythTV on an XBox. Does all the things you want, and of course it will run WxPython. But does that involve modding the Xbox?? As in messing with the hardware?? -- http://mail.python.org/mailman/listinfo/python-list
Re: Why doesn't join() call str() on its arguments?
news.sydney.pipenetworks.com [EMAIL PROTECTED] writes: Really ? Then why are you using python. Try import this at a Python prompt. I didn't invent Explicit is better than implicit. Python or most dynamic languages are are so great because of their common sense towards the implicit. Python is not most dynamic languages, and does not seem to implicitly cast objects into other types. Python may be dynamic, but it's also strongly typed, a feature I consider a benefit, though you are of course free to disagree. c = %s%s % (a, b) There is an implicit str(b) here. Not if you read the docs, as another poster has pointed out. ''.join([string, 2]) to me is no different then the example above. TypeError: sequence item 1: expected string, int found Which pretty much supports my initial argument -- if a non-string got into the list, something needs to be fixed, and it isn't the behavior of the join() method! Nick -- # sigmask || 0.2 || 20030107 || public domain || feed this to a python print reduce(lambda x,y:x+chr(ord(y)-1),' Ojdl!Wbshjti!=obwAcboefstobudi/psh?') -- http://mail.python.org/mailman/listinfo/python-list
Re: Stable GUI + wxPython memory leak
Peter Hansen wrote:
On which platform?
On Linux, and I'm watching the percentage of used memory with *top* or
*ps v* (I have 256 MB). The aplication started with 19% used and after
45 minutes playing I saw i eat up almost 70%.
I also noticed that:
from Tkinter import *
l = Listbox()
l.pack()
for i in range(20):
... l.insert('end', str(i)) # Occupy memory
...
l.delete(0, 'end') # Free the memory
Doesn't free the memory. The memory stays occupied. OK, when I do the
same thing again, no additional memory is occupied. He uses the same
memory allocated first time, but why doesn't he free it and why memory
isn't fread up even if I explicitly call
l.distroy()
del l
?!
Thank You.
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Re: Help needed for to build a CGI shell interface.
Slalomsk8er wrote: I don't get it with the popen (popen3 or subprocess). 1. How do I establish my pipes? 2. And how do I interact with the pipes (interactive CGI-page)? There are plenty of python + http frameworks out there - from simple cgi-like ones like mod_python to full fledged app servers like zope. As usual, google is your friend. No need to dig into the things you mentioned above - at least not for what you want to do right now. -- Regards, Diez B. Roggisch -- http://mail.python.org/mailman/listinfo/python-list
tiff via email-module
hi all, my problem is to get a tiff-file-attachment out of an email sent by a fax-server. When i try this with get_payload(decode='True') i get additional informations, looks like binary-mixed header-information, enveloping the tiff-data. I tried the following: Sending the email from outlook to a postfix-user and a file on the postfix-host as well. The file shows the stucture mentioned above. The mail for the postfix-user is deliverd correctly. So postfix must fetch the raw tiff-data too!?. Is there a way to get the raw tiff-data using the email-module? Any ideas? ralph -- http://mail.python.org/mailman/listinfo/python-list
Re: Stable GUI + wxPython memory leak
Viktor wrote: Doesn't free the memory. The memory stays occupied. OK, when I do the same thing again, no additional memory is occupied. He uses the same memory allocated first time, but why doesn't he free it and why memory isn't fread up even if I explicitly call the memory is released, but it's still assigned to the process. if, how and when it's returned to the operating system depends on a lot of things, most of which are out- side Python's control. (fwiw, this is how dynamic memory management works on most platforms). /F -- http://mail.python.org/mailman/listinfo/python-list
Is it possible to use the logging-module in a threadless environment?
I'd like to use a program (roundup) that imports the logging.config module on a machine where I could not get the thread and threading modules to compile. How dangerous is it to changing /lib/python2.4/logging/config.py to something like: import dummy_thread as thread, dummy_threading as threading Thanks in advance, Roger Erens -- http://mail.python.org/mailman/listinfo/python-list
Re: check if object is number
On Sat, 12 Feb 2005 16:01:26 -0800, rumours say that Michael Spencer [EMAIL PROTECTED] might have written: Yup, that's basically what I'm doing right now. The question was really how to define that adapter function. =) Steve OK - then my entry is: assert obj+1 = 1 :-) So -1 is not a number. -- TZOTZIOY, I speak England very best. Be strict when sending and tolerant when receiving. (from RFC1958) I really should keep that in mind when talking with people, actually... -- http://mail.python.org/mailman/listinfo/python-list
Re: Why Tk treat F10, F11, F12 diferently from F1...F9?
On Sun, 13 Feb 2005 00:10:35 -0200, rumours say that Gabriel B. [EMAIL PROTECTED] might have written: [snip: F10 in Motif activates the menu bar] i'm on windowsXP (what makes the F10 biding by default even more weird). Well, for now using the keysym_num will be more safe since i'm still getting they correct. It's not weird, it's the same in Windows as far as I remember (windows 3.0). F10 is the same as depressing Alt. -- TZOTZIOY, I speak England very best. Be strict when sending and tolerant when receiving. (from RFC1958) I really should keep that in mind when talking with people, actually... -- http://mail.python.org/mailman/listinfo/python-list
Re: Why doesn't join() call str() on its arguments?
Fredrik Lundh wrote: news.sydney.pipenetworks.com wrote: Nick Explicit is better than Implicit Really ? Then why are you using python. Python or most dynamic languages are are so great because of their common sense towards the implicit. You must have heard of never say never but never say always (as in always better) is more appropriate here. There are many cases of python's implicitness. a certain princess bride quote would fit here, I think. I'm not really familiar with it, can you enlighten please. What about a = string b = 2 c = %s%s % (a, b) There is an implicit str(b) here. nope. it's explicit: %s means convert using str(). ok you got me there, although it must be bad practice compared to c = %s%d % (a, b) because this is much more explicit and will tell you if b is ever anything other then an integer even though you may not care. from the documentation: %s String (converts any python object using str()). ''.join([string, 2]) to me is no different then the example above. so where's the %s in your second example? /F I'm not sure if this has been raised in the thread but I sure as heck always convert my join arguments using str(). When does someone use .join() and not want all arguments to be strings ? Any examples ? Regards, Huy -- http://mail.python.org/mailman/listinfo/python-list
Re: Stable GUI + wxPython memory leak
Peter Hansen [EMAIL PROTECTED] wrote: Viktor wrote: I just noticed that wxPython is leaking memory?! Playing with wxPython-demo, I started with 19MB used, and ended whith almost 150MB used?! It's wxPython 2.5.3.1 running on Python 2.4. On which platform? And how are you measuring this apparent memory consumption? And what are you doing to the demo to provoke it? (I've had a wxPython application significantly increase its memory footprint on Windows just from opening a file dialog.) -- \S -- [EMAIL PROTECTED] -- http://www.chaos.org.uk/~sion/ ___ | Frankly I have no feelings towards penguins one way or the other \X/ |-- Arthur C. Clarke her nu becomeþ se bera eadward ofdun hlæddre heafdes bæce bump bump bump -- http://mail.python.org/mailman/listinfo/python-list
Convert a raw pointer to IDispatch
Hi, I am trying to use the function CreateStreamOnHGlobal from python code (I need to pass an IStream object to MSXML, like I do in C++ code). I was able to retrieve a pointer on the IStream object in this way: from ctypes import * stream = c_int() windll.ole32.CreateStreamOnHGlobal(c_long(0), c_long(1), byref(stream)) print %x%stream.value The problem is that I would like to attach this pointer to a python IDispatch object (in Python only, not using a C++ DLL to do the stuff). Do you know a way to do it ? Thanks for your attention. -- http://mail.python.org/mailman/listinfo/python-list
Re: [newbie]How to install python under DOS and is there any Wxpython can be installed under dos?
john san wrote: Actually the windows running very good under the xbox-NTOS via xboxmediacenter. its just limited functions(not easy to programming the windows prog.), if we can find WxPython-like can be ported (I can import * from it to my xboxPython) )it will be a great great . You will have HD screen and web surfing on HDTV and computing on HDTV. think about it! That is a real thing the python-like lang. should to do otherwise just a garbage(toy). I assume you mean that without python the Xbox is just a toy.. Regards, Fuzzy http://www.voidspace.org.uk/python/index.shtml -- http://mail.python.org/mailman/listinfo/python-list
Re: pyFMOD writing a callback function in Python
Any opinion on pyFMOD vs. pySonic? -- http://mail.python.org/mailman/listinfo/python-list
Re: Stable GUI
Am Wed, 16 Feb 2005 06:19:27 -0800 schrieb Viktor: Which GUI is the most stable one? I don't need any fancy looking widgets (look and feel doesn't realy matter to me), I just need it to be rock stable and fast... Hi, For me pygtk is enough stable and fast. The reference is good: http://www.pygtk.org/pygtk2reference/index.html Thomas -- Thomas Güttler, http://www.thomas-guettler.de/ -- http://mail.python.org/mailman/listinfo/python-list
Re: Why doesn't join() call str() on its arguments?
Nick Vargish wrote: news.sydney.pipenetworks.com [EMAIL PROTECTED] writes: Really ? Then why are you using python. Try import this at a Python prompt. I didn't invent Explicit is better than implicit. Thanks for the pointer. Let's see how many zen points are for the OP's idea vs against Against Explicit is better than implicit. Special cases aren't special enough to break the rules. On the wall Errors should never pass silently. In the face of ambiguity, refuse the temptation to guess. There should be one-- and preferably only one --obvious way to do it. Although that way may not be obvious at first unless you're Dutch. Now is better than never. Although never is often better than *right* now. Namespaces are one honking great idea -- let's do more of those! For Beautiful is better than ugly. Simple is better than complex. Complex is better than complicated. Flat is better than nested. Sparse is better than dense. Readability counts. Although practicality beats purity. Unless explicitly silenced. If the implementation is hard to explain, it's a bad idea. If the implementation is easy to explain, it may be a good idea. Well this is clearly a goer ;-) Python or most dynamic languages are are so great because of their common sense towards the implicit. Python is not most dynamic languages, and does not seem to implicitly cast objects into other types. Python may be dynamic, but it's also strongly typed, a feature I consider a benefit, though you are of course free to disagree. c = %s%s % (a, b) There is an implicit str(b) here. Not if you read the docs, as another poster has pointed out. ''.join([string, 2]) to me is no different then the example above. TypeError: sequence item 1: expected string, int found Which pretty much supports my initial argument -- if a non-string got into the list, something needs to be fixed, and it isn't the behavior of the join() method! Nick -- http://mail.python.org/mailman/listinfo/python-list
os.walk()
Could someone demonstrate the correct/proper way to use os.walk() to skip certain files and folders while walking a specified path? I've read the module docs and googled to no avail and posted here about other os.walk issues, but I think I need to back up to the basics or find another tool as this isn't going anywhere fast... I've tried this: for root, dirs, files in os.walk(path, topdown=True): file_skip_list = ['file1', 'file2'] dir_skip_list = ['dir1', 'dir2'] for f in files: if f in file_skip_list files.remove(f) for d in dirs: if d in dir_skip_list: dirs.remove(d) NOW, ANALYZE THE FILES And This: files = [f for f in files if f not in file_skip_list] dirs = [d for d in dirs if dir not in dir_skip_list] NOW, ANAYLZE THE FILES The problem I run into is that some of the files and dirs are not removed while others are. I can be more specific and give exact examples if needed. On WinXP, 'pagefile.sys' is always removed, while 'UsrClass.dat' is *never* removed, etc. -- http://mail.python.org/mailman/listinfo/python-list
Re: os.walk()
rbt [EMAIL PROTECTED] wrote in message news:[EMAIL PROTECTED] Could someone demonstrate the correct/proper way to use os.walk() to skip certain files and folders while walking a specified path? I've read the module docs and googled to no avail and posted here about other os.walk issues, but I think I need to back up to the basics or find another tool as this isn't going anywhere fast... I've tried this: for root, dirs, files in os.walk(path, topdown=True): file_skip_list = ['file1', 'file2'] dir_skip_list = ['dir1', 'dir2'] for f in files: if f in file_skip_list files.remove(f) for d in dirs: if d in dir_skip_list: dirs.remove(d) I think the problem here is that you are removing elements from a list while traversing it. Try to use a copy for the traversal, like this: for f in files[:]: if f in file_skip_list files.remove(f) for d in dirs[:]: if d in dir_skip_list: dirs.remove(d) And This: files = [f for f in files if f not in file_skip_list] dirs = [d for d in dirs if dir not in dir_skip_list] This is not doing what you want because it just creates new lists and it doesn't modify the existing lists that the os.walk generator is using. -- http://mail.python.org/mailman/listinfo/python-list
Re: Is it possible to use the logging-module in a threadless environment?
On 17 Feb 2005 05:41:12 -0800 [EMAIL PROTECTED] (Roger) wrote: I'd like to use a program (roundup) that imports the logging.config module on a machine where I could not get the thread and threading modules to compile. How dangerous is it to changing /lib/python2.4/logging/config.py to something like: import dummy_thread as thread, dummy_threading as threading I believe it's a bug and logging/config.py should use the same approach as logging/__init__.py do: try: import thread import threading except ImportError: thread = None -- Denis S. Otkidach http://www.python.ru/ [ru] -- http://mail.python.org/mailman/listinfo/python-list
Re: Why doesn't join() call str() on its arguments?
news.sydney.pipenetworks.com wrote: Nick Vargish wrote: news.sydney.pipenetworks.com [EMAIL PROTECTED] writes: Really ? Then why are you using python. Try import this at a Python prompt. I didn't invent Explicit is better than implicit. Thanks for the pointer. Let's see how many zen points are for the OP's idea vs against Against Explicit is better than implicit. Special cases aren't special enough to break the rules. On the wall Errors should never pass silently. In the face of ambiguity, refuse the temptation to guess. There should be one-- and preferably only one --obvious way to do it. Although that way may not be obvious at first unless you're Dutch. Now is better than never. Although never is often better than *right* now. Namespaces are one honking great idea -- let's do more of those! For Beautiful is better than ugly. Simple is better than complex. Complex is better than complicated. Flat is better than nested. Sparse is better than dense. Readability counts. Although practicality beats purity. Unless explicitly silenced. If the implementation is hard to explain, it's a bad idea. If the implementation is easy to explain, it may be a good idea. From the point of view of someone who actually *tried* doing this to the relevant method, while maintaining backward compatibility. . . Against: Explicit is better than implicit Special cases aren't special enough to break the rules In the face of ambiguity, refuse the temptation to guess - there are plenty of ambiguious cases to handle Simple is better than complex (Semantics C code) - and much complexity in dealing with the ambiguities Errors should never pass silently. Unless explicitly silenced. - and a bunch of them are likely to indicate errors. Maybe. Readability counts (C code) - This makes the implemenation hard to read If the implementation is hard to explain, it's a bad idea. - or explain to anyone, too For: Beautiful is better than ugly. - the explicit calls to str() aren't that clean. There should be one-- and preferably only one --obvious way to do it. - Currently listcomp, genexp, map, string interpolation, etc IMO, the rest can be used to argue either side, or simply don't weigh heavily either way. The things that make it a real cow are the current behaviour of auto-promotion to the Unicode version when there are any Unicode strings in the list, and the existence of __str__ and __repr__ methods which actually return instances of unicode rather than str. Calling str() explicitly makes the different behaviours unsurprising. Trying to do the same thing behind the scenes has the potential to make the method behave *very* suprisingly depending on the objects involved. Cheers, Nick. -- Nick Coghlan | [EMAIL PROTECTED] | Brisbane, Australia --- http://boredomandlaziness.skystorm.net -- http://mail.python.org/mailman/listinfo/python-list
Re: Why doesn't join() call str() on its arguments?
In article [EMAIL PROTECTED], ! Nick Vargish [EMAIL PROTECTED] wrote: If a non-string-type has managed to get into my list-of-strings, then something has gone wrong and I would like to know about this potential problem. Thinking about where I use join(), I agree. If there's something other than a string in my list, either I know about it and can explicitly convert it (Explicit is better than implicit.) or it's an error, and Errors should never pass silently. -- \S -- [EMAIL PROTECTED] -- http://www.chaos.org.uk/~sion/ ___ | Frankly I have no feelings towards penguins one way or the other \X/ |-- Arthur C. Clarke her nu becomeþ se bera eadward ofdun hlæddre heafdes bæce bump bump bump -- http://mail.python.org/mailman/listinfo/python-list
Re: os.walk()
Roel Schroeven wrote: rbt wrote: The problem I run into is that some of the files and dirs are not removed while others are. I can be more specific and give exact examples if needed. On WinXP, 'pagefile.sys' is always removed, while 'UsrClass.dat' is *never* removed, etc. Keep in mind that the comparisons are done case sensitive; are you sure that there's no problem regarding uppercase/lowercase? I've noticed that. I've tried most all combinations possible with the same results. -- http://mail.python.org/mailman/listinfo/python-list
Re: os.walk()
snip
os.walk() is a generator. When you iterate over it, like in a for loop,
as
for r,ds,fs in os.walk(...):
r, ds and fs are set to new values at the beginning of each iteration.
If you want to end up with a list of files or dirs, rather than
processing them in the bodies of the file and dir for loops, you need
to keep a list of the files and dirs that os.walk gives you:
import os
dir_skip_list = ['sub2']
file_skip_list = []
keptfiles = list()
keptdirs = list()
for root, ds, fs in os.walk('c:\\bin\\gtest\\'):
for f in fs:
if f not in file_skip_list:
keptfiles.append(f)
for d in ds:
if d in dir_skip_list:
ds.remove(d)
else:
keptdirs.append(d)
keptfiles
['P4064013.JPG', 'P4064015.JPG', 'Thumbs.db', 'P4064060.JPG',
'P4064061.JPG', 'Thumbs.db', 'PC030088.JPG', 'P4224133.JPG',
'Thumbs.db']
keptdirs
['sub1', 'sub5', 'sub6']
There is something going on above that I don't quite understand, there
should be more directories, so if you can't get something working with
that, this gives you lists of files and dirs that you can then filter:
keptfiles = list()
keptdirs = list()
for r, ds, fs in os.walk('c:\\bin\\gtest'):
keptfiles.extend(fs)
keptdirs.extend(ds)
keptfiles
['P4064013.JPG', 'P4064015.JPG', 'Thumbs.db', 'P4064026.JPG',
'Thumbs.db', 'Thumbs.db', 'Thumbs.db', 'P4064034.JPG', 'Thumbs.db',
'P3123878.JPG', 'P4064065.JPG', 'Thumbs.db', 'P4064060.JPG',
'P4064061.JPG', 'Thumbs.db', 'PC030088.JPG', 'P4224133.JPG',
'Thumbs.db']
keptdirs
['sub1', 'sub2', 'sub3', 'sub5', 'sub6', 'sub8', 'SubA', 'sub9',
'sub6']
#filter away...
Hope this helps,
max
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Re: [newbie]How to install python under DOS and is there any Wxpython can be installed under dos?
oh, ya. Fuzzyman [EMAIL PROTECTED] news:[EMAIL PROTECTED] john san wrote: Actually the windows running very good under the xbox-NTOS via xboxmediacenter. its just limited functions(not easy to programming the windows prog.), if we can find WxPython-like can be ported (I can import * from it to my xboxPython) )it will be a great great . You will have HD screen and web surfing on HDTV and computing on HDTV. think about it! That is a real thing the python-like lang. should to do otherwise just a garbage(toy). I assume you mean that without python the Xbox is just a toy.. Regards, Fuzzy http://www.voidspace.org.uk/python/index.shtml -- http://mail.python.org/mailman/listinfo/python-list
Re: Why doesn't join() call str() on its arguments?
news.sydney.pipenetworks.com wrote:
I'm not sure if this has been raised in the thread but I sure as heck
always convert my join arguments using str(). When does someone use
.join() and not want all arguments to be strings ? Any examples ?
This has already been raised, but maybe not in exactly this context. You
don't want to convert your arguments to be strings if some of them are
unicode.
If I do:
res = str.join(', ', [a, b, c])
then res is of type str if, and only if, a, b, and c are of type str.
If any of a, b, or c are of type unicode, then res is unicode.
In effect, this means you don't have to worry about whether you are
manipulating str or unicode at this point in your program (kind of
comparable to not caring whether the integer you are using is int or long).
When you come to output the string you do need to care, as when it is
unicode you may have to encode it, but at least the internal manipulations
can ignore this possibility.
Of course you could just call unicode on everything but for simple
applications you might not want to handle unicode at all. That's not a
decision Python can make for you so it shouldn't guess.
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Re: Getting milliseconds in Python
On 2005-02-16, Brian Beck [EMAIL PROTECTED] wrote: seconds * 100 = milliseconds are you sure you know what a millisecond is? (duck) Touché. But it was a typo. Oh, you meant 'seconds / 100 = milliseconds'? (canard) -- http://mail.python.org/mailman/listinfo/python-list
Re: [newbie]How to install python under DOS and is there any Wxpython can be installed under dos?
yes. u need mod-xbox. since its be easy done and we already have OS, Python support what we need now is only that Python can easy to coding and show window program just like wt we can do under Windows. Lucas Raab [EMAIL PROTECTED] news:[EMAIL PROTECTED] Leif B. Kristensen wrote: john san skrev: Actually the windows running very good under the xbox-NTOS via xboxmediacenter. its just limited functions(not easy to programming the windows prog.), if we can find WxPython-like can be ported (I can import * from it to my xboxPython) )it will be a great great . You will have HD screen and web surfing on HDTV and computing on HDTV. think about it! That is a real thing the python-like lang. should to do otherwise just a garbage(toy). You can run Linux with MythTV on an XBox. Does all the things you want, and of course it will run WxPython. But does that involve modding the Xbox?? As in messing with the hardware?? -- http://mail.python.org/mailman/listinfo/python-list
Re: Getting milliseconds in Python
Curt wrote: Oh, you meant 'seconds / 100 = milliseconds'? (canard) I assume you're suggesting that there are two typos in my original post (the * and the 100)... Despite a millisecond being a thousandth of a second, given the number of seconds provided by the time module, he does have to *multiply* by a thousand to get the number of milliseconds. 2 seconds * 1000 = 2000 milliseconds So, aside from the 100 in the original post, it may look misleading, but that is what he would need to do... -- Brian Beck Adventurer of the First Order -- http://mail.python.org/mailman/listinfo/python-list
Re: [newbie]How to install python under DOS and is there any Wxpython can be installed under dos?
john san wrote: yes. u need mod-xbox. since its be easy done and we already have OS, Python support what we need now is only that Python can easy to coding and show window program just like wt we can do under Windows. You can't. DOS does not allow for graphical output - at least not in a way python supports it by standard toolkits like wxPython. That has nothing to do with python, btw. You won't find anything else that can do that - apart from some really old legacy toolkits that certainly aren't available today. Use either Linux with frambuffer output (see freevo) or a real Windows that is capable of showing a graphical ui. Maybe somehow the pygame sdl wrapper can be used for gui-stuff. SDL has had a DOS mode. But it is discontinued. -- Regards, Diez B. Roggisch -- http://mail.python.org/mailman/listinfo/python-list
Re: tiff via email-module
Arenz, Ralph wrote: hi all, my problem is to get a tiff-file-attachment out of an email sent by a fax-server. When i try this with get_payload(decode='True') i get additional informations, looks like binary-mixed header-information, enveloping the tiff-data. get_payload(decode=1) returns the decoded data. eg. the binary value of a file attachement. If you get additional information there is most likely something wrong with your message, or you are not traversing it correctly. You should do something like:: # untested def getAttachments(message): Returns attachments from message maintype = message.get_type() if maintype == 'application/octet-stream' : return [message.get_payload(decode=1)] if message.is_multipart(): attachments = [] for part in message.walk(): attachments.append(part.get_payload(decode=1)) return attachments return [] -- hilsen/regards Max M, Denmark http://www.mxm.dk/ IT's Mad Science -- http://mail.python.org/mailman/listinfo/python-list
Re: Problem using/installing numarray
Thanks, that explains why the CygWin Python will not import the .pyd
files:
imp.get_suffixes()
[('.dll', 'rb', 3), ('module.dll', 'rb', 3), ('.py', 'U', 1), ('.pyc',
'rb', 2)]
Doesn't look like there's a way to get the CygWin Python to load .pyd
files. So I guess I have to figure out why the build isn't working...
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Re: difference between class methods and instance methods
Duncan Booth wrote: John M. Gabriele wrote: I've done some C++ and Java in the past, and have recently learned a fair amount of Python. One thing I still really don't get though is the difference between class methods and instance methods. I guess I'll try to narrow it down to a few specific questions, but any further input offered on the subject is greatly appreciated: I'll try not to cover the same ground as Steven did in his reply. Thanks for taking the time to reply Duncan. 1. Are all of my class's methods supposed to take 'self' as their first arg? consider this: class Demo(object): def foo(self, x): print self, x @classmethod def clsmethod(cls, x): print cls, x @staticmethod def stmethod(x): print x instance = Demo() Calling a bound method, you don't pass an explicit self parameter, but the method receives a self parameter: bound = instance.foo bound(2) __main__.Demo object at 0x00B436B0 2 Note that it doesn't matter whether you call instance.foo(2) directly, or bind instance.foo to a variable first. Either will create a *new* bound method object, and the correct instance is used for the call. Za! What do you mean, create a new bound method object? I *already* created that method when I def'd it inside the 'class Demo' statement, no? This is significantly different from languages such as C++ and Javascript which are a real pain if you want to use a method as a callback. Calling an unbound method, you pass a self parameter explicitly (and it must be an instance of the class, *or an instance of a subclass*: unbound = Demo.foo unbound(instance, 2) __main__.Demo object at 0x00B436B0 2 A! See, coming from C++, the first thing I thought when I saw what you just wrote was, whoops, he shouldn't be calling that instance method via the class name -- it's a bad habit. Now I think I see what you mean: you may call an instance method in two ways: via an instance where you don't pass in anything for 'self', and via the class name, where you must supply a 'self'. Again is doesn't matter whether you do this in one step or two. The usual case for using an unbound method is when you have overridden a method in a derived class and want to pass the call on to a base class. e.g. Ok. Interesting. class Derived(Demo): def foo(self, x): Demo.foo(self, x) A class method is usually called through the class rather than an instance, and it gets as its first parameter the actual class involved in the call: Demo.clsmethod(2) class '__main__.Demo' 2 Derived.clsmethod(2) class '__main__.Derived' 2 Check. You can call a class method using an instance of the class, or of a subclass, but you still the get class passed as the first parameter rather than the instance: d = Derived d.clsmethod(2) class '__main__.Derived' 2 Ok, so it looks like it may lead to confusion if you do that. I wonder why the language allows it... A common use for class methods is to write factory functions. This is because you can ensure that the object created has the same class as the parameter passed in the first argument. Alternatively you can use class methods to control state related to a specific class (e.g. to count the number of instances of that exact class which have been created.) There is no equivalent to a class method in C++. Right. I see -- because in Python, a reference the actual class object is implicitly passed along with the method call. Whereas, C++ doesn't even have class objects to begin with. Static methods are like static methods in C++. You can call them through the class or a subclass, or through an instance, but the object used in the call is not passed through to the method: Demo.stmethod(2) 2 instance.stmethod(2) 2 Derived.stmethod(2) 2 d.stmethod(2) 2 2. Am I then supposed to call them with MyClass.foo() or instead: bar = MyClass() bar.foo() ? If you have an instance then use it. If the class method is a factory then you might want to create a new object of the same type as some existing object (but not a simple copy since you won't get any of the original object's state). Mostly though you know the type of the object you want to create rather than having an existing instance lying around. 3. Is bound method a synonym for instance method? Close but not quite. It is a (usually transient) object created from an unbound instance method for the purposes of calling the method. ... hmm... bound methods get created each time you make a call to an instance method via an instance of the given class? 4. Is unbound method a synonym for class method? Definitely not. Right. :) And if anyone's *really* daring: Where do the so-called static methods fit into all this? By the name of them, it sounds like the same thing as class methods... See above. -- --- remove zees if replying via email --- -- http://mail.python.org/mailman/listinfo/python-list
Re: difference between class methods and instance methods
John wrote: ... hmm... bound methods get created each time you make a call to an instance method via an instance of the given class? No, they get created when you create an actual instance of an object. So only at construction time. Creating them means taking the unbound method and binding the created object as first argument to the method. Thus each instance of a class Foo with a method bar has its own instance of bar - the bound method bar. But only one per object. -- Regards, Diez B. Roggisch -- http://mail.python.org/mailman/listinfo/python-list
Re: Getting milliseconds in Python
Martin Christensen wrote: A math teacher! A math teacher! My kingdom for a math teacher! Martin Man, this is the hottest topic on c.l.py since that Lazaridis guy... -- Brian Beck Adventurer of the First Order -- http://mail.python.org/mailman/listinfo/python-list
site indexer and search script
Hi, for an old intranet that is still used here, i would like to add a search function. I think there migth already be an indexer/search script available in python. I've googled and come across a few scripts but i'm not sure which one is really easy and good at the task. Any good scripts (and easy to configure) around? I would like to use python to generate the corresponding results page, what would i use for that, again bearing in mind that it needs to be done quite quickly so i cannot afford to waste to much time ? Is mod_python usable for such a simple page generation or would i better focus on Twisted or CherryPie? Thanks, Benedict -- http://mail.python.org/mailman/listinfo/python-list
Re: difference between class methods and instance methods
Diez B. Roggisch wrote: John wrote: ... hmm... bound methods get created each time you make a call to an instance method via an instance of the given class? No, they get created when you create an actual instance of an object. So only at construction time. Creating them means taking the unbound method and binding the created object as first argument to the method. Thus each instance of a class Foo with a method bar has its own instance of bar - the bound method bar. But only one per object. O. Unlike C++, where methods are not first class objects and you only have *one* that gets shared by all instances. I'm getting it. Thanks for the reply. :) ---J -- --- remove zees if replying via email --- -- http://mail.python.org/mailman/listinfo/python-list
Re: difference between class methods and instance methods
O. Unlike C++, where methods are not first class objects and you only have *one* that gets shared by all instances. Exactly - so unlike in c++, where you have to do ugly hacks if e.g. a C-lib takes a callback and you want to pass an instance method, you can do that in python. It's really great. -- Regards, Diez B. Roggisch -- http://mail.python.org/mailman/listinfo/python-list
Re: newbie question - iterating through dictionary object
-BEGIN PGP SIGNED MESSAGE-
Hash: SHA1
Miranda == mirandacascade [EMAIL PROTECTED] writes:
Miranda 1) Is there any advantage to use the
Miranda y = a.keys()
Miranda for z in y:
While you're at it, you could save y altogether and just use
for z in a.keys():
...
Miranda looping technique rather than the
Miranda for x in a:
Miranda looping technique?
I certainly don't see any advatages.
Miranda 2) What are the tradeoffs for using each of the techniques?
'for x in a:' is prettier to look at. :-) As you can see, it's also
slightly faster (at least for very small dictionaries), but unless
you're doing a _lot_ of them, it won't matter.
% python2.4 -m timeit -c a = {1:1, 2:2, 3:3, 4:4, 5:5} for x in a: pass
100 loops, best of 3: 1.63 usec per loop
% python2.4 -m timeit -c a = {1:1, 2:2, 3:3, 4:4, 5:5} for x in a.keys():
pass
10 loops, best of 3: 2.1 usec per loop
Martin
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Re: Getting milliseconds in Python
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Brian == Brian Beck [EMAIL PROTECTED] writes: Brian Man, this is the hottest topic on c.l.py since that Lazaridis Brian guy... ... which was really the point of my joke, even if it did belly flop somewhat. This whole discussions brought to mind a cartoon where a group of doctors were performing open heart surgery. One of them says, Okay, how many of us believe that the heart has _four_ chambers?, and a few of the others raise their hands. I intended it as a 'let's call in the professors to determine if 2+2=4', but, well... :-) Martin - -- Homepage: http://www.cs.auc.dk/~factotum/ GPG public key: http://www.cs.auc.dk/~factotum/gpgkey.txt -BEGIN PGP SIGNATURE- Version: GnuPG v1.2.5 (GNU/Linux) Comment: Using Mailcrypt+GnuPG http://www.gnupg.org iEYEARECAAYFAkIUyzAACgkQYu1fMmOQldWVdACdHLxtUi4TtFCl0ZW6wf65Hu9M ioMAoMWAHrkS5lhQw5V0cJXVO1nk76MO =6MXl -END PGP SIGNATURE- -- http://mail.python.org/mailman/listinfo/python-list
Re: difference between class methods and instance methods
John wrote:
Steven Bethard wrote:
John M. Gabriele wrote:
class C(object):
@classmethod
def f(cls, *args):
# do stuff
Sorry -- I'm not as far along as you suspect. :) I've
never yet seen this @classmethod syntax. I'm supposing that
it's part of this so-called new-style class syntax.
This is syntactic sugar in Python 2.4 for:
class C(object):
def f(cls, *args):
# do stuff
f = classmethod(f)
So if you'd like to check the docs, look in the builtins for classmethod
(and staticmethod):
http://docs.python.org/lib/built-in-funcs.html
From your reply, I gather that, unless I'm using this special
syntax (@classmethod or @staticmethod), all my def's are supposed
to take 'self' as their first arg.
Yup. You're of course welcome to name it whatever you like, but the
methods defined in your class (when not wrapped with classmethod,
staticmethod, etc.) will all be called with an instance of the class as
their first argument. So you need to make sure 'self' or something like
it is the first parameter to the function.
So then, are all def's -- that take 'self' as their first --
argument -- in a class statement, instance methods?
Basically, yes. (Again, assuming they're not wrapped with anything.)
Consider the difference between str.join and ''.join:
py str.join
method 'join' of 'str' objects
py ', '.join
built-in method join of str object at 0x01233620
Hmm... weird.
Ok, the point here is that str.join and ', '.join are not the same
object. The reason is that, when the ', ' instance of str is created,
new bound method objects are created for each of the instance methods
in str. These bound methods all know that the first argument to their
functions is ', '.
py ', '.join(['a', 'b', 'c'])
'a, b, c'
Check.
py str.join(', ', ['a', 'b', 'c'])
'a, b, c'
[snip]
What's happening here?
str.join is the unbound method of the str object. So just like you
have to declare 'self' as the first argument of all your instance
methods, the writer of the str object methods also declared 'self' as
the first argumetn to str.join. So str.join looks something like:
class str(object):
...
def join(self, sequence):
...
So when you access it like str.join(...) you should be passing it an
instance and a sequence. On the other hand, the bound method created
for ', ' has already bound the instance, so it no longer expects the
'self' argument to be passed in.
HTH,
STeVe
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Re: newbie question - iterating through dictionary object
On 2005-02-17, [EMAIL PROTECTED] [EMAIL PROTECTED] wrote:
1) Is there any advantage to use the
y = a.keys()
for z in y:
looping technique rather than the
for x in a:
looping technique?
Not really.
2) What are the tradeoffs for using each of the techniques?
for x in a can be more efficient since it allows the
dictionary to return key values one at a time instead of
creating a list containing all of them. For small dictionaries
it won't matter.
Here's another choice, that's sometimes handy:
d = {1:'one',2:'two',3:'three'}
for k,v in d.items():
print k,v
1 one
2 two
3 three
I wouldn't recommend this for large dictionaries.
--
Grant Edwards grante Yow! RELATIVES!!
at
visi.com
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Re: Loading functions from a file during run-time
f=open(bar.txt) import imp fs=imp.new_module(fs) exec f in fs.__dict__ rests are the same althought why use anything other than .py, when you import .py, it get compiled into .pyc and it load faster next time -- http://mail.python.org/mailman/listinfo/python-list
Re: newbie question - iterating through dictionary object
[EMAIL PROTECTED] wrote: 1) Is there any advantage to use the y = a.keys() for z in y: looping technique rather than the for x in a: looping technique? 2) What are the tradeoffs for using each of the techniques? Calling dict.keys creates a list in memory of the keys to the dict. Using the dict directly in the for-loop (which implicitly calls __iter__) will only load one key into memory at a time. The only time you should call keys is if you *really* need a list. If you're just going to iterate over them in a for-loop, you should definitely use the latter technique. STeVe -- http://mail.python.org/mailman/listinfo/python-list
Re: newbie question - iterating through dictionary object
Grant Edwards wrote:
Here's another choice, that's sometimes handy:
d = {1:'one',2:'two',3:'three'}
for k,v in d.items():
print k,v
1 one
2 two
3 three
I wouldn't recommend this for large dictionaries.
Yes, for large dictionaries, you should use:
for k, v in d.iteritems():
print k, v
STeVe
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Re: Pausing a program - poll/sleep/threads?
I don't think time.sleep() will work too well, I think it will cause the program to hang around in the foreground, and prevent the GUI updating. I'll give it a try just to make sure, as I can't figure out the signal/alarm thing (the alarm only seems to trigger when I click a button, not after n-seconds -- http://mail.python.org/mailman/listinfo/python-list
Creating properties with decorator like syntax
Hi, Is there any way of making properties using a decorator? The current way of creating a property seems inelegant. Something like this imaginary snippit would be nice, IMHO. class C(object): @make_property def x(self): def getx(self): return self.__x def setx(self, value): self.__x = value def delx(self): del self.__x Regards, Will McGugan -- http://mail.python.org/mailman/listinfo/python-list
Re: difference between class methods and instance methods
Diez B. Roggisch wrote: John wrote: ... hmm... bound methods get created each time you make a call to an instance method via an instance of the given class? No, they get created when you create an actual instance of an object. So only at construction time. Creating them means taking the unbound method and binding the created object as first argument to the method. Thus each instance of a class Foo with a method bar has its own instance of bar - the bound method bar. But only one per object. This is badly wrong. John was correct. Bound methods get created whenever you reference a method of an instance. If you are calling the method then the bound method is destroyed as soon as the call returns. You can have as many different bound methods created from the same unbound method and the same instance as you want: inst = C() f1 = inst.foo f2 = inst.foo f1, f2 (bound method C.foo of __main__.C instance at 0x00B03F58, bound method C.foo of __main__.C instance at 0x00B03F58) f1 is f2 False f1 is inst.foo False Every reference to inst.foo is a new bound method. -- http://mail.python.org/mailman/listinfo/python-list
Re: Help needed for to build a CGI shell interface.
Diez B. Roggisch wrote: Slalomsk8er wrote: I don't get it with the popen (popen3 or subprocess). 1. How do I establish my pipes? 2. And how do I interact with the pipes (interactive CGI-page)? There are plenty of python + http frameworks out there - from simple cgi-like ones like mod_python to full fledged app servers like zope. As usual, google is your friend. No need to dig into the things you mentioned above - at least not for what you want to do right now. What do I want to do? I am building an admintool (deamon and client) and for this I need to script a interface to the shell, with the console ansi escape sequences, whitch is fully transparent for the user. I do not want Zope or Plone. I want Python and XUL. Google is my friend but I did not found the answers I need to understand the concepts behind the parts (python internals and shell/terminal things). Please point me to the info, I can not find it (tryed for some days) or post code so I can reverse engenieer ;) and adapt it. Thanks, Dominik -- http://mail.python.org/mailman/listinfo/python-list
Re: Pausing a program - poll/sleep/threads?
Damn! signal is not supported on Windows. time.sleep() doesn't work, as I suspected:: def info(self): sleep(5) self.info() Basically causes the function to pause, then call itself again, all in the foreground :-( I'm thinking some sort of thread timer is the way to go, but really don't understand threads -- http://mail.python.org/mailman/listinfo/python-list
Re: Why doesn't join() call str() on its arguments?
news.sydney.pipenetworks.com wrote: Fredrik Lundh wrote: a certain princess bride quote would fit here, I think. I'm not really familiar with it, can you enlighten please. (Taking a guess at which quote /F had in mind...) Vezzini: Inconceivable! Inigo:You keep using that word. I do not think that it means what you think it means. Jeff Shannon -- http://mail.python.org/mailman/listinfo/python-list
Re: [EVALUATION] - E02 - Support for MinGW Open Source Compiler
Stephen Kellett wrote: [...] closing thread http://groups-beta.google.com/group/comp.lang.python/msg/f2ae9cdbe16676d1 . -- http://lazaridis.com -- http://mail.python.org/mailman/listinfo/python-list
Re: [EVALUATION] - E02 - Support for MinGW Open Source Compiler
Mike Meyer wrote: [...] closing thread http://groups-beta.google.com/group/comp.lang.python/msg/f2ae9cdbe16676d1 . -- http://lazaridis.com -- http://mail.python.org/mailman/listinfo/python-list
Re: [EVALUATION] - E02 - Support for MinGW Open Source Compiler
Bruno Desthuilliers wrote: [...] closing thread http://groups-beta.google.com/group/comp.lang.python/msg/f2ae9cdbe16676d1 . -- http://lazaridis.com -- http://mail.python.org/mailman/listinfo/python-list
Re: multimethod (or rather overloading) in Python
anton muhin wrote: Correction: Of course, I can imagine some metaclasses magic that would allow to code: class MyClass(WithOverloading): @overloadMethod(A) def someMetod(self, _): ... But it would rather convoluted: the best idea I have so far is to mangle methods name in the manner most of C++ compilers do. Stupid me. Of course, name magling is impossible and unnecessary. Sorry. Still the question remains. with the best regards, anton. -- http://mail.python.org/mailman/listinfo/python-list
Re: [EVALUATION] - E02 - ULTIMATE RECIPE TO RESOLVE ALL ISSUES
Peter Maas wrote: Ilias Lazaridis schrieb: I'm a newcomer to python: Sorry, I'm breaking my promise to post only once to this thread. I'm breaking my 'promise' to close this thread. But I've found the ultimate recipe to resolve all issues of this and other similar threads: Please read http://nobelprize.org/medicine/educational/pavlov/ and then do something useful :) I don't think that this would change the disastrous communication behaviour of the python community [1]. For sure it has not changed yours. And I don't think that this would change anything on the huge amounts of off-topic posts [including yours, and of course my reply to yours]. This thread proofs simply the inability of this community [1] to focus on a simple essence. - [1] community: the publically writing, within c.l.python . -- http://lazaridis.com -- http://mail.python.org/mailman/listinfo/python-list
Re: Pausing a program - poll/sleep/threads?
Simon John wrote: I'm writing a PyQt network client for XMMS, using the InetCtrl plugin, that on connection receives a track length. [...] So, how would I make a Python program automatically call a function after a preset period of time, without the Python process running in the foreground (effectively single-tasking)? I'm not familiar with Qt/PyQt myself, but the GUI toolkits I *am* familiar with all have a concept of a timer. Basically, you create a timer that, when the specified amount of time has elapsed, will either deliver an event/message to your application's event queue or will directly call the callback function you provide. However, I'd suggest that you may not want to wait for the entire length of the current track, especially if some other process or user (on any machine) may have access to the same XMMS application. What happens when, after the song's been playing for a few seconds, someone skips to the next track? Presumably, you'll want your network client to detect that and update appropriately. This implies that you should check back in with the XMMS server every few seconds at least. (You can still use a timer to do this; just have it fire periodically every second or so, rather than only after several minutes.) Jeff Shannon -- http://mail.python.org/mailman/listinfo/python-list
Re: Calling a function from module question.
Sean, if you are asking what I think you are asking (I don't think name hiding is the issue), you can use from module_name import * and you will end up with all of the functions at session scope. You can use the 'as' to alias the function names if you wish from module_name import fn1 as myfn1, fn2 as myfn2 but, um, that gets confusing. -- http://mail.python.org/mailman/listinfo/python-list
Re: Alternative to standard C for
On Sat, 2005-02-05 at 10:49, BJörn Lindqvist wrote: I am quite new to Python, and have a straight simple question. In C, there is for (init; cond; advance). We all know that. In Python there are two ways to loop over i=A..B (numerical.): 1) i = A while iB: ...do something... i+=STEP This is indeed quite ugly. You rarely need such loops in Python and with some thinking you can often translate the C-equivalent to something more pythonic. As you guessed, your second problem is best solved with a generator function - xrange(). It is completely equal to range() except that it returns a generator instead of a list. It seems I need constructs like this all of the time i = 0 while i len(somelist): if oughta_pop_it(somelist[i]): somelist.pop(i) else: i += 1 There has to be a better way... Any thoughts? James - 7. Obsession with National Security Fear is used as a motivational tool by the government over the masses. -- http://mail.python.org/mailman/listinfo/python-list
Re: Convert a raw pointer to IDispatch
Roger That [EMAIL PROTECTED] writes: Hi, I am trying to use the function CreateStreamOnHGlobal from python code (I need to pass an IStream object to MSXML, like I do in C++ code). I was able to retrieve a pointer on the IStream object in this way: from ctypes import * stream = c_int() windll.ole32.CreateStreamOnHGlobal(c_long(0), c_long(1), byref(stream)) print %x%stream.value The problem is that I would like to attach this pointer to a python IDispatch object (in Python only, not using a C++ DLL to do the stuff). Do you know a way to do it ? What do you want to do with this pointer? Pass it to a function called via ctypes? Thomas -- http://mail.python.org/mailman/listinfo/python-list
namespace collisions
Hi, I'm accumulating a number of small functions, which I have sensibly put in a single file called 'util.py'. But it occurs to me that with such a generic name it could cause problems with other modules not written by myself. Whats the best way of handling this? If I put it in a common location in my Python path, should I call it willsutil.py? TIA, Will McGugan -- http://mail.python.org/mailman/listinfo/python-list
Re: [newbie]How to install python under DOS and is there any Wxpython can be installed under dos?
Diez B. Roggisch [EMAIL PROTECTED] writes: Maybe somehow the pygame sdl wrapper can be used for gui-stuff. SDL has had a DOS mode. But it is discontinued. What exactly is discontinued? pygame? SDL? Thomas -- http://mail.python.org/mailman/listinfo/python-list
Re: check if object is number
Christos TZOTZIOY Georgiou wrote: On Sat, 12 Feb 2005 16:01:26 -0800, rumours say that Michael Spencer [EMAIL PROTECTED] might have written: Yup, that's basically what I'm doing right now. The question was really how to define that adapter function. =) Steve OK - then my entry is: assert obj+1 = 1 :-) So -1 is not a number. At least not a legal one for Steven's function as I understood it Michael -- http://mail.python.org/mailman/listinfo/python-list
msnp, friends list
I'm currently using the msnp.py code from Manish Jethani's project. I havn't been able to get the friends list to update like it should. it works once out of about every 25 times the program loads. Has anyone been able to implement his code and get the friends list to actively update? Or have any suggestions? Any info would be great. Thanks. -- http://mail.python.org/mailman/listinfo/python-list
Re: [newbie]How to install python under DOS and is there any Wxpython can be installed under dos?
Leif B. Kristensen wrote: john san skrev: pure DOS, old pc, used for teaching . want show some windows under DOS (under Python). curses is a text-based interface that will let you build windowed applications like you could with the crt unit in Turbo Pascal of those golden days. I've no idea if anyone's compiled it for the 16-bits DOS platform, though. Curses is a *nix interface. There are attempts at a work-alike package for Windows, which by all reports are not very successful. Whether any of those would maintain their already-limited functionality under DOS is questionable. There *are* similar-but-not-compatible libraries for DOS... or perhaps I should say *were*, because I have no idea where one might find such a thing now. (Though I presume that Google would be the best starting place.) One would then need to find/create a Python wrapper for that library... Jeff Shannon -- http://mail.python.org/mailman/listinfo/python-list
