🌐 Mailman 3 April 2003 - Python-list - python.org

Histogram (was: When Python outruns C++ )
by mertz＠gnosis.cx April 1, 2003

April 1, 2003

Julian Tibble <chasm(a)rift.sytes.net> wrote previously: ...histogram program... |file of size ~80MB, the C program outperformed the python one |$ (time ./words < biginput) > /dev/null # 0m8.476s |$ (time python words.py < biginput) > /dev/null # 1m59.747s This much difference is surprising to me. I figured there had to be something wrong with Tibble's Python version; but it seems like it's not that bad. The fastest Python histogram program I know is below (the example came up before :-))... but in a quick test against a smaller 5MB file, the below takes over half the time of Tibble's (FWIW, the version I present in my book, <http://gnosis.cx/TPiP/chap2.txt>, is between the two in speed--but mine has a few more options). I tested under 2.3a2, FWIW. ------------------------------------------------------------------------ #!/usr/local/bin/python # $Id: wordfreq.python,v 1.9 2001/05/11 17:44:00 doug Exp $ # http://www.bagley.org/~doug/shootout/ # # adapted from Bill Lear's original python word frequency counter # # Joel Rosdahl suggested using translate table to speed up # word splitting. That change alone sped this program up by # at least a factor of 3. # # with further speedups from Mark Baker import sys def main(): count = {} i_r = map(chr, range(256)) trans = [' '] * 256 o_a, o_z = ord('a'), (ord('z')+1) trans[ord('A'):(ord('Z')+1)] = i_r[o_a:o_z] trans[o_a:o_z] = i_r[o_a:o_z] trans = ''.join(trans) rl = sys.stdin.readlines lines = rl(4095) while lines: for line in lines: for word in line.translate(trans).split(): try: count[word] += 1 except KeyError: count[word] = 1 lines = rl(4095) l = zip(count.values(), count.keys()) l.sort() l.reverse() print '\n'.join(["%7s\t%s" % (count, word) for (count, word) in l]) import time start = time.clock() main() sys.stderr.write('%4.2f seconds\n' % (time.clock()-start)) -- mertz@ _/_/_/_/_/_/_/ THIS MESSAGE WAS BROUGHT TO YOU BY:_/_/_/_/ v i gnosis _/_/ Postmodern Enterprises _/_/ s r .cx _/_/ MAKERS OF CHAOS.... _/_/ i u _/_/_/_/_/ LOOK FOR IT IN A NEIGHBORHOOD NEAR YOU_/_/_/_/_/ g s

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Questions on linked lists
by Kevin Reeder April 1, 2003

April 1, 2003

The tutorial I'm working through has a section on Linked Lists that has left me puzzled. I believe I got the basic concept of nodes, embedded references, and cargo, but when the discussion turned to wrappers, helpers, preconditions and invariants, I started taking on water. Can anyone here point me to documentation with a good explanation of this subject esp in the context of Python? Kevin

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Is Jython development still undergoing?
by John Smith April 1, 2003

April 1, 2003

I apologize if this is a wrong plact to ask. First, I'm so thankful to the Jython project. It's so wonderful tha I just can't have enough of it. But I can't help but wondering if Jython development is still alive. The latest version (2.1) is about 2 release behind CPython (2.3alpha now) and is 15 months old. Is Jython 2.2 on the horizon? I really like to port my code full with "class mylist(list): " to jython. Thanks in advance.

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Terminal-based text editor with color syntax hilighting
by Dave Benjamin April 1, 2003

April 1, 2003

Hey folks, I often write Python over a terminal session, and I really enjoy working with color syntax hilighting, so my editor of choise for the past year or so has been Jed. I've heard that it's possible to get color hilighting to work with Emacs, but so far I've been unable to get that working. (Note: I'm talking about an SSH session, not an XTerm. Text only.) I think Jed is a nice editor, and it's very fast, but I'm wondering if there are any other editors that support this feature. Does anyone know? Thanks, Dave

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weird float() behavior
by pball＠umich.edu April 1, 2003

April 1, 2003

Hi, so I had a confusion with int() (why an exception for int('3.1416')? why not just return 3? ok, I read threads from many years ago) and float(). I've been sifting through the c.l.py archives, but this seems new. Basically, int(float(someString)) seems always to return zero with a particular mix of gcc and python versions. (note carefully the machine name, gcc & python versions) [pball@wylbur]% python Python 2.2.2 (#1, Mar 29 2003, 23:20:21) [GCC 3.2.2 20030322 (Gentoo Linux 1.4 3.2.2-r2)] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> s = '16073.0' >>> int( float(s) ) 0 >>> hello! int(i)==0?? that's not right. I went to another machine. [pball@silas]% python Python 2.2.1 (#1, Aug 30 2002, 12:15:30) [GCC 3.2 20020822 (Red Hat Linux Rawhide 3.2-4)] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> s = '16073.0' >>> int(float(s)) 16073 >>> This is more what I'd expect. So a bit more: [pball@piglet]% python Python 2.2.2 (#1, Mar 20 2003, 02:05:28) [GCC 3.2.2] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> s = '16073.0' >>> int(float(s)) 16073 >>> Again, what I'd expect. To be complete: pball@mina> python Python 1.5.2 (#1, Apr 3 2002, 18:16:26) [GCC 2.96 20000731 (Red Hat Linux 7.2 2 on linux-i386 Copyright 1991-1995 Stichting Mathematisch Centrum, Amsterdam >>> s = '16073.0' >>> int( float(s) ) 16073 >>> ok, it seems pretty likely that it's the gentoo python 2.2.2 with the bleeding-edge gcc 3.2.2. I found that float was triggering it, but actually, int() is just very sick: [pball@wylbur]% python ~ Python 2.2.2 (#1, Mar 29 2003, 23:20:21) [GCC 3.2.2 20030322 (Gentoo Linux 1.4 3.2.2-r2)] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> s = '3.1415' >>> int( float(s) ) -610 >>> int( 3.1416 ) 0 >>> int( 3.1415 ) -610 >>> int( 3.1417 ) 0 >>> int( 3.1419 ) Traceback (most recent call last): File "<stdin>", line 1, in ? OverflowError: float too large to convert >>> Ok, that's enough. Has anyone else seen this? Any ideas how I broke it so completely? Is there more info I can post to better identify it? Is there a regression test we could add to the post-compile process to flag this? Thanks - PB.

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PySqlite for the Python 2.3a
by Driver, David April 1, 2003

April 1, 2003

So, I emailed a few days ago saying that I was going to try to compile pySqlite and install it for 2.3. Well after a few evenings of dinking around in the source code, I now know that I have no understanding of the C++ languages or of building an install package for windows. Is there any plans to do an installer for the alphas? Is there another way to get the package installed for windows? Any help is appreciated. Sqlite is a beautiful piece of work. I can't wait to get it to work on 2.3. During the day I work in an all Microsoft shop programming VB for SQL server. At night I get to program Python. BTW, Does anybody know of any work with sqlite and VB? I have seen that there are ODBC drivers for .net, and there is a custom compiled version of Sqlite out there that doesn't look like it keeps up with development.

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Ann: Stackless Perl 4.0
by Christian Tismer April 1, 2003

April 1, 2003

Dear Python/Perl Community, Insiders have known this from the beginning, and they were waiting for this to happen for much too long time: Stackless 3.0 has been dead-born from the beginning. The new live language is Stsckless Perl 5.0! This is not due to the nature of Stackless, it is due to the nature of Python. There is a better language than Python, and its name is PERL! Python has always been a recursively implemented language. Perl has been stackless from the very early days. My brain has always been thinking the Python way. But my heart always was beating the Perl rhythm & $blues. Now my time has come, and there is again A BIG CHANGE OF STACKLESS: Finally, after all the years of development, it became not only natural but also consequent, to abandon the very hard way of merging the principles of Stackless Python 1.0 and 2.0 into 3.0. Instead, I invented Stackless Perl 5.0. ================================================================ Stackless Perl 5.0 The implementation was incredibly simple. I just had to drop 95 percent of my C implementation for Stackless Python 3.0, change the object model, and to invent three new Perl objects. These are: stackless::tasklet (about 20 methods) stackless::channel (about 120 methods) stackless::continuation (about 4 methods) The latter is a re-incarnation of an old idea, which was most popular in many Scheme dialects, but seems to me most appropriate in the Stackless Perl context. There are now infinitely countable ways to express new ways to express new or existing control structures by Perl continuations. This is an incredible, outstanding feature, which clearly contradicts the Python "one size fits all" paradigm. Or was it "there is only one way to do it"? (What to do, at all?) Stackless Perl has Default UNIVERSAL methods, for example: isa(tasklet) isa returns true if its object is blessed into a subclass of tasklet isa is also exportable and can be called as a sub with two arguments. This allows the ability to check what a reference points to. Example use UNIVERSAL qw(isa); if(isa($ref, 'tasklet')) { #... } can(become) can check to see if its object has a method called become, if it does then a reference to the sub is returned, if it does not then undef is returned. And so on. The number of well-formed examples is so incredible large. Isn't that just great! ? Oh, I love it so much. Such a match! Another very relevant example is the solution to *all* existing PEP308 proposals: The stackless Perl dynamic syntax parser has been extended in a way that covers every possible PEP 308 alternative to implement ternary operators in a completely individual way: Every individual is now able to spell her/his own way of understanding the myriads of possible solutions to implement the different incarnations of $if expr $elif expr $else expr $endif Perl constructs and their relatives, in any imaginable and unimaginable perlish way. This is of course due to the radical use of continuations, together with dynamic syntax rules. I have to admit that this example code took me another two days, and three days of theoretically testing every thinkable implementation possible. There is no single way to say it. Just say it. 100 Python people will just say "say what?" or "ni!". 10000 Perl people will love and support my message. Messias, you did so absolutely right, finally! Isn't that amount of love and support worth a paradigm change? I'm very happy that I became converted to this remarkable language in such a short time. It took me only two days to do the whole implementation (that is, abandoning almost all of the code). I will spend the next six months doing the debugging, and the next 10 years doing the porting: I'm now happy to tell this to all my customers and sponsors: After having ported all your code from Stackless Python 1.0 to 2.0 and almost to 3.0, I now would like to be paid for porting your whole Python application to Stackless Perl 5.0. I know you are happy with this since you knew from the beginning, that this would be most effective in the first place. Sorry for messing with Python for all the years. This was a major design flaw, that I realized a few days before. This principle of very fast design changes makes Open Source so attractive to me. Downloads are avaliable here: http://stackless.apriperl.org This was a statement about Stackless Perl 5.0, just an intermediate step towards Stackless Perl 6.0, which will make use of the outstanding feature of white space overloading with continuations. This feature will be presented on the Python/Perl Integration marathon sprint session in August 2005 in Luxemburg. Please apply early, this is a really small country. BTW., can any knowleadgeable body please give me a crash course in Perl programming? I would like to be able to produce some testing code, but I didn't have the time to RTFM, yet. :-) cheers -- chris(a)stackless.apriperl.org p.s.: This message was intentionally not cross-posted, since most readers will be assimilated to the Perl community anyway, the sooner or later... -- Christian Tismer :^) <mailto:tismer@tismer.com> Mission Impossible 5oftware : Have a break! Take a ride on Python's Johannes-Niemeyer-Weg 9a : *Starship* http://starship.python.net/ 14109 Berlin : PGP key -> http://wwwkeys.pgp.net/ work +49 30 89 09 53 34 home +49 30 802 86 56 pager +49 173 24 18 776 PGP 0x57F3BF04 9064 F4E1 D754 C2FF 1619 305B C09C 5A3B 57F3 BF04 whom do you want to sponsor today? http://www.stackless.com/

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To get text in a Text widget.
by denis gaultier April 1, 2003

April 1, 2003

I just want to know how to do to get text typed in a Text widget. I don't know what kind of parameter I must give to the "get" function. Thanks for your help.

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Re: List of given type
by sjmachin＠lexicon.net April 1, 2003

April 1, 2003

Zaur Shibzoukhov <szport(a)fromru.com> wrote in message news:<mailman.1049055286.13086.python-list(a)python.org>... > I need standard list of objects with a given type: > list of int, list of float, list of list, list of dict, list of string, ... - list of any type. > A silly question: WHY???

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Re: [ANNOUNCE] Fifth release of PythonCAD now available.
by aahz＠pythoncraft.com April 1, 2003

April 1, 2003

In article <mailman.1048870490.22835.python-list(a)python.org>, Art Haas <ahaas(a)airmail.net> wrote: > >With this release I am also making a request for help in setting up >a mailing list. The lack of a mailing list for people interested in >working on PythonCAD to find one another and discuss development issues >is a hindrance in adding developers to the project. I do not have the >hardware or connection to set up a mailing list on my own, so I would >appreciate a few suggestions for sites willing to provide this service. Two options: * Request a mailing list on python.org, see http://mail.python.org/ * Set up a SourceForge project -- Aahz (aahz(a)pythoncraft.com) <*> http://www.pythoncraft.com/ This is Python. We don't care much about theory, except where it intersects with useful practice. --Aahz, c.l.py, 2/4/2002

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