🌐 Mailman 3 October 2004 - Python-list - python.org

Search and Replace in a text.
by Dong Ge Oct. 1, 2004

Oct. 1, 2004

I'm a new beginner of Python. I want to convet "Text 1" to "Text 2" below. How to do it? __ Dong Ge 2004.10.01 Text 1: ... Layer: Tv-Frame Flags: 0x0 Attr: 1 Focus Point: 0 0 0 Layer: Tv-pic Flags: 0x2300 Attr: 1 Focus Point: 0 0 0 Layer: Tv-shell Flags: 0x0 Attr: 1 Focus Point: 0 0 0 ... Text 2: ... Layer: Tv-Frame Flags: 0x0 Attr: Tv-Frame Focus Point: 0 0 0 Layer: Tv-pic Flags: 0x2300 Attr: Tv-pic Focus Point: 0 0 0 Layer: Tv-shell Flags: 0x0 Attr: Tv-shell Focus Point: 0 0 0

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Manipulate HTML documents via data structure
by C. Barnes Oct. 1, 2004

Oct. 1, 2004

Python provides HTML parsing through the HTMLParser and htmllib modules. For my application, I needed to search through an HTML document in a nonlinear fashion and dynamically change parts of the document. The most logical way to do this is to translate HTML back and forth to a data structure. I wrote a module called htmldata, available from: http://oregonstate.edu/~barnesc/htmldata/ Example: >>> from htmldata import dumps, loads >>> o=loads('<img src=hi.gif alt="blah">foo</body>') >>> o [('img', {'src':'hi.gif', 'alt':'blah'}), 'foo', ('/body', {})] >>> dumps(o) '<img alt="blah" src="hi.gif">foo</body>' Pros: * More powerful for HTML editing. * Easy to reproduce the original document (at least, a document that is HTML-equiv to the original). Cons: * Less user friendly than HTMLParser module. I tested it on several popular sites. Feedback, bug reports, etc appreciated. - Connelly Barnes __________________________________ Do you Yahoo!? New and Improved Yahoo! Mail - 100MB free storage! http://promotions.yahoo.com/new_mail

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Re: List rotation
by David Vaughan Oct. 1, 2004

Oct. 1, 2004

Here's a quick way to transpose, keeping all the sharps and flats correct. You could dress it up a bit by writing a Tune subclass of list with a transpose method, particularly if there are other things you want to do with tunes :) David # Define a long list of notes, each a fifth higher than its predecessor: fifths = [] for suffix in ['bb','b','','#','##']: for note in ['F','C','G','D','A','E','B']: fifths.append(note+suffix) fifths.append('F###') # So len(fifths)==36 and we can wrap round correctly print 'fifths ==',fifths print # Translate between note names and indices in this list of fifths: def m_ord(note_name): return fifths.index(note_name) def m_str(note_index): """Note: index can be any value, and wraps round appropriately.""" return fifths[note_index % len(fifths)] # Do the main work: def offset(sourcekey, destkey): """Returns offset in fifths which represents key-change.""" return m_ord(destkey) - m_ord(sourcekey) def transpose(tune, offset): """Transposes a tune (=list of notes) by given key-change offset.""" return [m_str(m_ord(note)+offset) for note in tune] # And show it off: tune = ['C','E','B','F'] print 'Tune is',tune for key in ['G', 'F', 'Dbb']: t = offset('C', key) print 'Transposition of tune from C to',key,'is',transpose(tune,t) David Vaughan Structural Analyst GIFFORD AND PARTNERS LTD Carlton House, Ringwood Road, Woodlands, Southampton, SO40 7HT, UNITED KINGDOM Tel: +44 (0)23 8081 7500 Fax: +44 (0)23 8081 7600 Email: David.Vaughan(a)gifford.uk.com Web: http://www.gifford.uk.com _____ This e-mail and any files transmitted with it are intended solely for the use of the individual or entity to whom they are addressed and may be confidential. If you are not the intended recipient or the person responsible for delivering the e-mail to the intended recipient, be advised that you have received this e-mail in error and that any use, dissemination, forwarding, printing or copying of this e-mail is strictly prohibited.

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Re: python vs c#
by aleaxit＠yahoo.com Oct. 1, 2004

Oct. 1, 2004

Steve Holden <steve(a)holdenweb.com> wrote: ... > pedant I had real trouble with. It reads "Some village in Texas is > missing their idiot", and the reason for my perplexity was, while I feel Aha, I have my pet anti-peeve on that one issue, _singular "their"_ (and "they", but we can argue that one once the easier possessive case is more accepted;-). I may have read and appreciated too much 18th-century and earlier English...;-) -- anyway, <http://www.crossmyt.com/hc/linghebr/austheir.html> expresses my own feelings in the matter pretty well (lots of useful links from that page, too). > this week, I'm much more prepared to let people break the rules when I > think that they realize they *are* breaking the rules. I have less > patience with those who either don't know (sad) or don't care > (inexcusable) about the rules. And what about those of us who are convinced that (some of) the rules are _wrong_ -- that '''18th-century grammarians started making arbitrary judgements as to what is "good English" and "bad English", based on a kind of pseudo-"logic" deduced from the Latin language, that has nothing whatever to do with English''', and that such _bloopers_ as the ban against "singular their" (and other even more blatant cases, such as the ban against "splitting ifinitives" and against ending a sentence with a preposition...) should be fought against...? > > called (with an expensive Latin term) "constructio ad sensum", i.e. you > > conjugate the verb in accordance with what the word represents, rather than > > with what it grammatically is. > > > Ultimately, language is intended to serve the purpose of communication, > and we shouldn't be too upset to see it mangled as long as it serves > that purpose. But when I hear politicians speak in sentences that don;t > even make sense (and hear rooms full of people applauding them, making > it obvious that no critical thought intervenes), *then I start to get my > dander up. There'll be a special room in hell for people who don;t > understand that language is *the* critical component of thought. I have no disagreement whatsoever with this. But the "rules of language" (mostly, a kind of guidelines...;-) that one should cherish for proper communication may often have little to do with grammar per se. Passive forms are grammatically correct, for example, but more often than not they make expression of ideas needlessly contorted -- we see a lot of those in technical and scientific writing, where we're often shy about choosing a _subject_ for our sentences... and often strive to avoid a singular "they"!-). Politicians (not necessarily the kind that run for elections) love the obfuscation passives often bring, of course. "Singular 'they' is widely considered incorrect", for example, craftily avoids naming a subject _because any subject would point out the thesis' weakness_ -- by saying "Pedants widely consider ..." one would reveal one's colors, by saying "Native speakers of English widely consider ..." one would express a direct lie that's easily shown up as such. Admittedly, the role of language is often to communicate _with ambiguity_ -- this may be sad, or even morally repugnant, but it's a fact... language evolved as a survival trait of human beings, and pretty often being able to communicate with ambiguity, so as to trick somebody and yet later be able to defend the claim that all you said was perfectly true, is obviously adaptive. Creative ambiguity has often been the only way some treatise or contract could be "sold" to the voters or stockholders of both nations or firms, enabling the politicians or executives of each side to interpret the words that were being signed in such a way as to mollify their constituency... So, in fighting to express ourselves clearly and directly, we _are_ indeed fighting against the grain of a substantial portion of language's biological purpose (helped, fortunately, by _another_ portion of it;-). In this fight, good rules help (particularly, they help a good writer who's able to pick the one case in a hundred where even a good rule is best broken in the advantage of clarity and directness), but bad rules hinder even more... Alex

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Re: python vs c#
by aleaxit＠yahoo.com Oct. 1, 2004

Oct. 1, 2004

Jan Dries <jan.dries(a)dcube-resource.be> wrote: ... > IIRC from back when I was in school (long time ago), both forms are correct. > At least in Dutch. Strictly spoken it should be "a few is enough" or "a > number of people has died". But the plural form is also accepted, and it is The Dutch are wondefully pragmatic... > called (with an expensive Latin term) "constructio ad sensum", i.e. you ...and so were the Latins. > conjugate the verb in accordance with what the word represents, rather than > with what it grammatically is. In Italian, this kind of freedom holds only for a few specific "idioms of collectivity" -- "un certo numero di persone", "una grande quantita` di persone", "la maggioranza delle persone". And even then, in many subcases, it depends on whether the verb expresses a collective action or a plurality of individual actions (some cases remain ambiguous). A rea-life example...: "La maggioranza degli italiani vive in un appartamento" ("A majority of Italians lives in an apartment", with the verb in the singular form) was once stated on TV by a politician and led to universal derision and unending jokes (even among his political allies) about how crowded that one apartment must be; in this case he should have said "vivono in appartamenti" ("live in apartments"), with the verb (and apartments;-) in the plural form. I suspect that this particular example does carry over to some other languages;-). Alex

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New to python, baffled by program output
by Lazareth＠gmail.com Oct. 1, 2004

Oct. 1, 2004

Hiya to whoever might stumble across this. I've recently taken up learning how to script/program in python. I've made my first program, a simple fahrenheit-celsius converter, both ways. For some reason I fail to comprehend, the program writes a line of "None" when rerun in a while loop. Here is the code: ---START--- def choice_c(): print celsius = input("Input celsius: ") print "Fahrenheit: ",cel_fah(celsius) print def choice_f(): print fahrenheit = input("Input fahrenheit: ") print "Celsius: ",fah_cel(fahrenheit) print def cel_fah(placeholder): return 9.0/5.0*placeholder+32 def fah_cel(placeholder): return (placeholder-32.0)*5.0/9.0 def options(): print "press 'c' to convert celsius to fahrenheit." print "press 'f' to convert fahrenheit to celsius." print "press 'q' to exit program." choice = "n" options() while choice != "q": choice = raw_input("Choice: ") if choice == "c": choice_c() elif choice == "f": choice_f() print options() ---END--- Any of you know why it prints that line? Is is just my comp? If any applies, how to get around it? Would greatly appreciate the help.

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Re: python vs c#
by Jan Dries Oct. 1, 2004

Oct. 1, 2004

Bengt Richter wrote: [... ] > I almost posted a similar comment ;-) OTOH ... > How many relevant points do you need to start a debate? > How would you answer that question? > > A few is enough? > A few are enough? > A few relevant points suffices, or a few relevant points suffice? > A small number suffices, or a small number suffice? > A dozen is sufficient? > A dozen are sufficient? > > I suspect that there are some semantic subtleties at work. > I.e., when you focus mentally on the few points as a single > collection, the singular forms feel right, but when you focus on > the few points as separate entities, plural forms feel right. > Thus you want the verb (e.g.,is/are) to agree numerically with > _some entities_, or with _a collection_, according to your focus. > I think some sentences can be read either way, depending on which > way your attention is directed (e.g. by word order and discourse > context etc.) "A few" can work as noun or adjective, it seems. IIRC from back when I was in school (long time ago), both forms are correct. At least in Dutch. Strictly spoken it should be "a few is enough" or "a number of people has died". But the plural form is also accepted, and it is called (with an expensive Latin term) "constructio ad sensum", i.e. you conjugate the verb in accordance with what the word represents, rather than with what it grammatically is. Regards, Jan

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Re: A newbie in more need....
by Steve Holden Oct. 1, 2004

Oct. 1, 2004

Robert Brewer wrote: > Chris Patton wrote: > >>I am writing a program that writes a number of classes, which are all >>fundementally the same thing. The only thing that is different is the >>names. Therefore, I need to write a bunch of classes in the quickest >>time I can. Here's what I was thinking of: >> >>num = 1 >>while num < 20: >> exec 'class bug'+num+':' >> exec ' gender = "m"' >> exec ' size = 0' >> exec ' skill = 0' >> >>Obviously, the "exec" statement severley slows the time it takes to >>write these classes. I need a new method! If possible I would like to >>avoid the use of the "exec" statement alltogether. > [excellent fumanchu code] having said that, usually when somebody suggests they need to dynamically create names in this way, it's often an indication that the created objects should be kept in a dictionary. How are you going to look these things up? What will be making the creator calls to bug1(), bug2(), and so on, and why couldn't it make calls to bug[1](), bug[2](), and so on? A little more detail might get you an even better solution. regards Steve

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RE: A newbie in more need....
by Robert Brewer Oct. 1, 2004

Oct. 1, 2004

Chris Patton wrote: > I am writing a program that writes a number of classes, which are all > fundementally the same thing. The only thing that is different is the > names. Therefore, I need to write a bunch of classes in the quickest > time I can. Here's what I was thinking of: > > num = 1 > while num < 20: > exec 'class bug'+num+':' > exec ' gender = "m"' > exec ' size = 0' > exec ' skill = 0' > > Obviously, the "exec" statement severley slows the time it takes to > write these classes. I need a new method! If possible I would like to > avoid the use of the "exec" statement alltogether. classtest.py ---- import types for x in xrange(20): n = 'bug%s' % x globals()[n] = types.ClassType(n, (object,), {'gender': 'm', 'size': 0, 'skill': 0}) del n del x ---- >>> import classtest >>> dir(classtest) ['__builtins__', '__doc__', '__file__', '__name__', 'bug0', 'bug1', 'bug10', 'bug11', 'bug12', 'bug13', 'bug14', 'bug15', 'bug16', 'bug17', 'bug18', 'bug19', 'bug2', 'bug3', 'bug4', 'bug5', 'bug6', 'bug7', 'bug8', 'bug9', 'types'] >>> dir(classtest.bug8) ['__class__', '__delattr__', '__dict__', '__doc__', '__getattribute__', '__hash__', '__init__', '__module__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__str__', '__weakref__', 'gender', 'size', 'skill'] >>> classtest.bug8.gender 'm' Robert Brewer MIS Amor Ministries fumanchu(a)amor.org

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Re: List rotation
by M. Clift Oct. 1, 2004

Oct. 1, 2004

Hi Dennis, So much for it being late here. I just had to look over your code before I go to bed. Excellent stuff, just what was needed : ) Can I ask are you writing a python music app? Just curious, as there doesn't seem to be many around. Malcolm

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