🌐 Mailman 3 April 1999 - Python-list - python.org

Dealing with faults matters (was: Is Python dying?)
by claird＠Starbase.NeoSoft.COM Aug. 27, 2003

Aug. 27, 2003

In article <3706f449.12085377(a)news.cybercity.dk>, Morten Christensen <mmc(a)vip.cybercity.dk> wrote: >On 31 Mar 1999 06:01:03 -0600, claird(a)Starbase.NeoSoft.COM (Cameron >Laird) wrote: >>*I* certainly discuss it. Anyone who understands >>that exception-handling is important I invite to >>realize that exception-handling on the sociologi- >>cal-organizational dimension has an even bigger >>multiplier. >> >>This is a plank of my "Visual C considered profes- >>sional malpractice" campaign. > >??? > >...I understand exception handling and regard it as very important, >although the (Visual) C++ implementation is really awful (as everyone >who have experienced "unexplainable" Visual C++ exceptions of unknown >origin and type knows ).... I also know a lot about how exception >handling is actually implemented in modern OO languages such as C++ >(this was the subject I wrote my master thesis on).... > >HOWEVER, I have NO clue about what you mean by exception-handling as a >multiplier on the sociological-organization dimension :-) I would like >to find out. Can you explain? . . . Happily. Excuse my giddiness, please; I see that that last message *did* wander too far into the land of obscurity. Here's what I was saying: exception-handling is important. Programs that intelligently use exception-handling mechanisms are better programs. Exception-handling is even more important to people. People and organizations that deal with exceptions intelligently, and don't pre- tend that everything should be without fault, are better people and organizations. In fact, a correct computer program often has over half its lines devoted to accomo- dating error. A wise person will have good ways to respond to criticism/problems/diffi- culties/...; dealing with success is relatively easier. -- Cameron Laird http://starbase.neosoft.com/~claird/home.html claird(a)NeoSoft.com +1 281 996 8546 FAX

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pythonwin COM Update link out of date
by bernhard＠alpha1.csd.uwm.edu June 17, 1999

June 17, 1999

http://www.python.org/ftp/python/pythonwin/pwindex.html#oadist Gives a bad link to the MS Microsoft Knowledge Base article Q164529. The link is bad and I cannot relocate the article with the search engine on that site and other methods... :( The closest I could get was: http://support.microsoft.com/support/kb/articles/Q139/4/32.asp from http://support.microsoft.com/support/downloads/LNP195.asp Hmmmm.... is there a potential danger in installing oadist.exe? Bernhard

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Designing Large Systems with Python
by David Steuber June 9, 1999

June 9, 1999

Over my programming life, I have used a 'cowboy' programming style. Once I have a general idea for a solution to a problem, I start coding, using the text editor as sort of an etch-o-scetch. This works fine for programs under about 10klocs (thousand lines of code), but it is rather fragile and doesn't hold up to larger programs or the requested additions of un-anticipated features. I've noticed the acedemic and industry attempts to solve the problem. OOA/OOD, UML, design patterns, et al are all proposed solutions. Meanwhile, languages like Ansi Common Lisp have had features that allow you to prototype and build a large system at the same time. That is, the specification of the system becomes the system. People have done the same thing with Visual Basic, so I am told. What I am wondering about is the suitability of Python for specifying, a large system and building a prototype. I have gotten myself rather entrenched in the cowboy style and I would love it if Python supported that for larger systems. One other thing. Is the documentation that comes with Python sufficient to gain mastery of the language, or should I consider buying (yet) another book? -- David Steuber http://www.david-steuber.com If you wish to reply by mail, _please_ replace 'trashcan' with 'david' in the e-mail address. The trashcan account really is a trashcan. A long memory is the most subversive idea in America.

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while (a=b()) ...
by Marco Mariani May 13, 1999

May 13, 1999

Hi all language lawyers! Which one is more ugly? ===== c = curs.fetchone() while c: print c c = curs.fetchone() ===== while 1: c = curs.fetchone() if c: print c else: break ===== Is there an elegant way? while curs.fetchone() print $_ :-))) -- "If you're going to kill someone there isn't much reason to get all worked up about it and angry. Any discussions beforehand are a waste of time. We need to smile at Novell while we pull the trigger." - Jim Allchin, Microsoft corp. -

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Re: IDLE !
by Marc Saric May 10, 1999

May 10, 1999

Boris Borcic wrote: > > I am having my first look at 1.5.2 and IDLE (on Win95). Had that look too, and found it a very nice and usefull tool: Some things I would like to see in an updated version: Cursor-up-and-down-history in the command shell, like in PTUI. Some key-bindings seem to be problematic (at least with a german keyboard; you cant press "CTRL+ [" for indentation for example). On Unix (SuSE 6.0 to be exact) I can't manage to get proper Windows-style copy and paste (CTRL+C, CTRL+V) (I don' like the Unix-key-bindungs, and therefore changed that to the windows-settings). Maybe it's just me who is too stupid, and someone may help me... -- Bye, Marc Saric Lehrstuhl fuer Biophysik Projektgruppe Theoretische Biophysik http://www.bph.ruhr-uni-bochum.de/ Ruhr-Universitaet Bochum Germany

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1.5.2 Build Snag
by Charles Y. Choi May 9, 1999

May 9, 1999

Folks - In trying to build Python 1.5.2 on a Sparc Solaris 2.5.1 machine using gcc 2.8.1 I get this: -- ar cr libpython1.5.a getbuildinfo.o ranlib libpython1.5.a true cd Modules; make OPT="-g -O2" VERSION="1.5" \ prefix="/usr/local" exec_prefix="/usr/local" \ LIBRARY=../libpython1.5.a link make[1]: Entering directory `/export/home/cchoi/src/Python-1.5.2/Modules' gcc python.o \ ../libpython1.5.a -lsocket -lnsl -ldl -lm -o python Undefined first referenced symbol in file __muldi3 ../libpython1.5.a(longobject.o) ld: fatal: Symbol referencing errors. No output written to python make[1]: *** [link] Error 1 make[1]: Leaving directory `/export/home/cchoi/src/Python-1.5.2/Modules' make: *** [python] Error 2 -- Anybody here have a similar experience? Strangely enough, I get a successful build using gcc version 2.5.6. Thanks! -Charles

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Using Python for Modular Artificial Intelligence code
by Tim Auld May 8, 1999

May 8, 1999

Hi all, I've been designing a large game project, and I want it to be easily extensible. It's a space combat/exploration/trade game, in the spirit of the original Elite. What I want to be able to do is add new units to the game while the player is in the middle of a game that has lasted weeks (or any arbitrary length of time) already. I've started looking into Python as the AI scripting language for this purpose, but I'm having trouble seeing exactly how I could do this. I want a message passing architecture - so one object in the game world sends a message to another for interpretation (along with a Python tuple for the parameters of the message perhaps). This requires a two way interface between my C++ code and the Python script loaded for the particular game object. My question is, how can I load the Python script, let my C++ object call functions within the Python script, and provide a callback for the Python script to call methods in the C++ object? Thanks, Tim ________________________ astro(a)tne.net.au tim(a)ratbaggames.com

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RE: Python too slow for real world
by Brian Lloyd May 8, 1999

May 8, 1999

> Hi All, > > first off all: Sorry for that slightly provoking subject ;-) ... > > I just switched from perl to python because I think python makes live > easyer in bigger software projects. However I found out that perl is > more then 10 times faster then python in solving the > following probelm: > > I've got a file (130 MB) with ~ 300000 datasets of the form: > > >px0034 hypothetical protein or whatever description > LSADQISTVQASFDKVKGDPVGILYAVFKADPSIMAKFTQFAGKDLESIKGTAPFETHAN > RIVGFFSKIIGELPNIEADVNTFVASHKPRGVTHDQLNNFRAGFVSYMKAHTDFAGAEAA > WGATLDTFFGMIFSKM > > The word floowing the '>' is an identifier, the uppercase > letters in the > lines following the identifier are the data. Now I want to read and > write the contens of that file excluding some entries (given by a > dictionary with identifiers, e.g. 'px0034'). > > The following python code does the job: > > from re import * > from sys import * > > def read_write(i, o, exclude): > name = compile('^>(\S+)') # regex to fetch the identifier > l = i.readline() > while l: > if l[0] == '>': # are we in new dataset? > m = name.search(l) > if m and exclude.has_key(m.group(1)): # excluding current > dataset? > l = i.readline() > while l and l[0] != '>': # skip this dataset > l = i.readline() > pass > o.write(l) > l = i.readline() > > f = open('my_very_big_data_file','r') # datafile with ~300000 records > read_write(f, stdout, {}) # for a simple test I don't exclude > anything! > > It took 503.90 sec on a SGI Power Challange (R10000 CPU). An > appropiate > perl script does the same job in 32 sec (Same method, same loop > structure)! > > Since I've to call this routine about 1500 times it's a very big > difference in time and not realy accaptable. > > I'd realy like to know why python is so slow (or perl is so fast?) and > what I can do to improove speed of that routine. > > I don't want to switch back to perl - but honestly, is python > the right > language to process souch huge amount of data? > > ... > Please do convince me being a python programmer does not mean > being slow > ;-) > > Thanks very much for any help, > > Arne > Arne, While I'm not going to go near comparing Python to Perl, I will comment that different languages are just that - different. As such, the approach you would take in one language may not be the most appropriate (or comparable in speed or efficiency) to the approach you would take in another. The question here (IMHO) is not Python's appropriateness for processing large datasets (a fair number of scientist-types do this all the time), or even the speed of Python in general, but using the most appropriate algorithms in the context of the language in use. For example, Perl is very regex-centric, so your example Perl implementation is probably perfectly appropriate for Perl. Python tends to be more optimized for the general case, and if it were _me_, I wouldn't bother with using regular expressions in this case,. Since you have a predictable file format, there are more specific (and efficient) Python tools that you could use here. There are also some general optimizations that can be used in places where speed is an issue, such as avoiding repeated attribute lookups (esp. in loops). This version of your read_write function uses the same basic algorithm, but forgoes re for more specific tools (slicing, string.split) and has some examples of optimizations to mimimize attribute lookups. I haven't timed it or anything, but I'd be surprised if it wasn't noticeably faster. Hope this helps! import sys, string def read_write(input, output, exclude): # These assignments will save us a lot of attribute # lookups over the course of the big loop... ignore=exclude.has_key readline=input.readline write=output.write split=string.split line=readline() while line: if line[0]=='>': # knowing that the first char is a '>' and that # the rest of the chars up to the first space are # the id, we can avoid using re here... key=split(line)[0][1:] if ignore(key): line=readline() while line and line[0] != '>': # skip this record line=readline() continue write(line) line=readline() file=open('my_very_big_data_file','r') # datafile with ~300000 records read_write(f, sys.stdout, {}) Brian Lloyd brian(a)digicool.com Software Engineer 540.371.6909 Digital Creations http://www.digicool.com

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Read MS Access 97 *.mdb files with python??
by gemodek＠t-online.de May 5, 1999

May 5, 1999

Does somebody know some piece of soft which can this?? Or does somebody know if the description of the format ia avaible (for free of course). Thanks Stephan

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Python documentation updated!
by Fred L. Drake May 5, 1999

May 5, 1999

The documentation for Python 1.5.2 is now available. The online version is available at: http://www.python.org/doc/ Archives of the documentation in HTML, LaTeX, PDF, and PostScript formats are available at the same location, and may also be downloaded via FTP from: ftp://ftp.python.org/pub/python/doc/ If you have any questions or comments on the documentation, please send email to: python-docs(a)python.org Many modules have been documented (166 total!), including both new and old modules. There have been some additional refinements of the "look" of the online version, especially for those of you with CSS enabled in your Web browsers. There is also more extensive hyperlinking within the Python Library Reference for your convenience. A new document, "Documenting Python", is now included. Though still young, this is a useful reference for documentation contributors. It includes a great deal of information on the markup used for the Python documentation, as well as a discussion of where we'll go from here. Windows users: If you installed Python using the installer rather than by building from source, you can get the updated documentation by downloading the HTML archive and unpacking it into the "Doc" directory of your installation. Some re-organization of the documentation area on the Web site should make it easier to locate and download documentation. Thanks go out to all the individuals who have contributed sections or sent in comments and bug reports; this release of the documentation is substantially better thanks to the efforts of the Python community! Enjoy! -Fred -- Fred L. Drake, Jr. <fdrake(a)acm.org> Corporation for National Research Initiatives

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