🌐 Mailman 3 November 2005 - Tutor - python.org

Postgresql+Python -tutorial?
by Olli Rajala Feb. 11, 2006

Feb. 11, 2006

Hi! I've been using MySQL up this day, but would like to convert my program to use Postgresql. There seems to be awful lots of tutorials for MySQL+Python, but not so many for Postgresql+Python. Where should I start? I'm not very good at database things, but have written some little programs with MySQL+Python/Php/Java. So, if you have some good tutorials or something else info, I'd be glad to know! Oh, I can install additional modules, but it would be great if Ubuntu had them... Thanks! -- Olli Rajala <>< Tampere, Finland http://www.students.tut.fi/~rajala37/ "In theory, Theory and Practice should be the same. But in practice, they aren't." - Murphy's Proverbs

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files - strings - lists
by Andrzej Kolinski Dec. 5, 2005

Dec. 5, 2005

I want to create a program that uses data from text files, makes appropriate calculations and produces report. First I need to find out what is the right way to retrieve appropriate information from an input file. This is a typical format of the input file: 1 Polonijna Liga Mistrzow |from the heading portion 26 wrzesnia 2005 |only 6 12 6 4 1 |'6' and '4' will be needed 0 1 0 Bohossian - Kolinski |all names and 1 |all scores 1.000 9 13 19 |(3rd column - 2.000 2 4 16 |'13', '4', '8', '6' 1.000 10 8 17 |will be needed 0.000 8 6 17 | Szadkowska - Szczurek | 2 |same here 0.000 11 16 20 | 3.000 1 -4 14 | 3.500 3 -7 13 2.500 10 13 19 .................. 1 1 |skip the rest 1 1 1 |(at least for now) 6 4 5 10 8 3 9 1 11 2 12 7 -50 -7 7 0 0 0 400 0 0 -110 -2 2 -130 1 -1 100 -1 1 110 -4 4 150 4 -4 400 0 0 -90 -1 1 100 6 -6 100 -1 1 420 4 -4 110 5 -5 -480 -1 1 1310 15 -15 ............ Should I use string manipulations or convert a file to lists of lists to retrieve names and numbers? I have unsuccessfully tried to code using the latter but I couldn't overcome the fact that lists representing each raw of a text file have different lengths. How could I associate each name with a score (a sum of scores)? _/_/ _/ _/ _/ _/ _/ _/ _/_/_/_/ _/ _/ _/ _/ _/ _/ _/ _/ _/ _/ Andrzej Kolinski office 416.652.4256 cell. 416.948.7767

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Is it a good idea to use TKInter to change my password program into a GUI?
by Nathan Pinno Dec. 3, 2005

Dec. 3, 2005

Hey all, Is it a good idea to use TKInter to change my password program into a GUI? I know it needs improvements, and I've noted them below: [code] #This is for a password protected program to store passwords. import getpass password = "hello" # This should instead load a file with the password in it. sitelist = {} def load_file(pw): import os filename = 'passcard.txt' # Weak, because any text file editor can read the usernames and passwords! if os.path.exists(filename): store = open(filename,'r') for line in store: site = line.strip() ID = store.next().strip() pw[site] = ID else: store = open(filename,'w') # create new empty file store.close() def save_file(pw): store = open('passcard.txt',"w") for site,ID in sitelist.items(): store.write(site + '\n') store.write(ID + '\n') store.close() def main_menu(): print "1) Add a login info card" print "2) Lookup a login info card" print "3) Remove a login info card" print "4) Print Login info list" print "9) Save and Exit" def add_site(): print "Add a login info card" site = raw_input("Site: ") ID = raw_input("User ID and passcard, seperated by a space: ") # seperated should be spelt separated. sitelist[site] = ID def lookup_site(): print "Lookup a login info card" site = raw_input("Site: ") if sitelist.has_key(site): print site,sitelist[site] else: print site," was not found." def remove_site(): print "Remove a login info card" site = raw_input("Site: ") if sitelist.has_key(site): del sitelist[site] else: print site," was not found." def print_login_info(): print "Login Info" for site in sitelist.keys(): print "Site: ",site," \tID Passcard: ",sitelist[site]+"\n" # There should be a way to change the password, or add it for first time users. print "The Password Program" print "By Nathan Pinno" print load_file(sitelist) answer = getpass.getpass("What is the password? ") while password != answer: print "The password is incorrect." answer = getpass.getpass("What is the password? ") print "Welcome to the second half of the program." while 1: main_menu() menu_choice = int(raw_input("Choose an option (1-4, or 9: ")) if menu_choice == 1: add_site() elif menu_choice == 2: lookup_site() elif menu_choice == 3: remove_site() elif menu_choice == 4: print_login_info() elif menu_choice == 9: break else: print "That's not an option!" save_file(sitelist) print "Have a nice day!" [/code] Is it possible to salvage it? Give me your honest advice. Nathan Pinno

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Beautiful Soup, inserting a node?
by Bob Tanner Dec. 2, 2005

Dec. 2, 2005

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Is there a way to insert a node with Beautiful Soup? I found away to append "things". But <html> <head> <title>Blah </title> </head> <body> <h1>Foo! </h1> </body> </html> I'd like to insert a <div> tag, like this: <html> <head> <title>Blah </title> </head> <body> <div id="header"> <h1>Foo! </h1> </div> </body> </html> - -- Bob Tanner <tanner(a)real-time.com> | Phone : (952)943-8700 http://www.real-time.com, Minnesota, Linux | Fax : (952)943-8500 Key fingerprint = AB15 0BDF BCDE 4369 5B42 1973 7CF1 A709 2CC1 B288 -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.2 (GNU/Linux) iD8DBQFDi8kqfPGnCSzBsogRAtUrAKCptkOKxAYa4k1FQsQdBdT64sLoaQCfdo22 lHR84OMn37JOpzJ5x/lp+IA= =2AJE -----END PGP SIGNATURE-----

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Scientific Notation + 18 Digit Pecision
by Hubert Fitch Dec. 1, 2005

Dec. 1, 2005

Hi Danny! (Python 2.3 IDLE GUI in WindowsXP Home edition) Thank you and the others who have sent replies! Attached to this file is a Rich Text File using "Save Copy As" from the Python Shell display. This will give an example of the desired formatted output. Some displayed lines are long, so I use legal size paper and landscape mode for printing this RTF file. Methods for turning on true division? A. Install the new Python, when it is available. When will this be available? B. from__future__import division This will work properly in an IDLE Python Shell, if I type it in, but not when it is present in .py modules. I see that it was read from the .py file by the python shell, but the behaviour in the shell still is not changed from integer division to normal division. (I put the statement at the beginning of my .py modules.) C. -Qnew I did not understand how to get and install Qnew, so I searched on the information below, and got a lot of results (1100), that confused me further. D. customized parser and evaluator This approach might be the best, but before I consider it, I must get the two affected fuunctions working. I saved the function modules that you refactored for me, into separate files, but should probably put them all into one file later. 1. Extract Equation 2. EvaluateEquation 3. PrintEquationAndValue 4. DisplayPyFile and my 5. Calling Program Module When I ran the caling module, (and got the indentation right in the function modues) all modules appeared to work except for the PrintEquationAnd Value Function which gives a syntax error for "if value:" with an arrow pointing to value. Reproduced below are the four function modules. and the calling module, and included is the original display module. # printEquation.py ############################################ def PrintEquationAndValue(equation, value): """Prints out the equation and its value.""" if value: name, assignment, comment = equation print "%10s = %18.15e (%s)\t[%s]" % (name, value, assignment, comment) else: print "%s not defined. %s" % (name, assignment) ############################################ # extractEquaiton.py def ExtractEquation(line): """Either returns a 3-tuple (name, assignment, comment) from the line, or None if we can't extract a definition from the line.""" line = line.strip() if not line: return None leftAndRight = line.split('#',2) comment = '' if len(leftAndRight) > 1: comment = leftAndRight[1] assignment = leftAndRight[0] leftAndRight = assignment.split('=') if len(leftAndRight) == 2: name = leftAndRight[0].strip() return (name, assignment, comment) return None # evaluateEquation.py # ############################################## def EvaluateEquation(equation, context): """Evaluates the equation in a given context. If we can't get a value, returns None.""" assert equation != None name, assignment, comment = equation exec(assignment, context) return context.get(name, None) ############################################## # new2DisplayPyFile.py # ############################################# def NewDisplayPyFile(fname, context=None): if context is None: context = globals() f = open(fname) lines = f.readlines() f.close() for line in lines: equation = ExtractEquation(line) if equation: value = EvaluateEquation(equation, context) printEquationAndValue(equation, value) else: print line ############################################## Original display function module. (Notice that I added the from future statement) from __future__ import division def DisplayPyFile(fname, context=None): if context is None: context = globals() f = open(fname) lines = f.readlines() f.close() for line in lines: line = line.strip() if not line: continue leftAndRight = line.split('#',2) comment = '' if len(leftAndRight)>1: comment = leftAndRight[1] assignment = leftAndRight[0] leftAndRight = assignment.split('=') if len(leftAndRight) == 2: name = leftAndRight[0].strip() exec(assignment, context) if context.get(name,None) is not None: value = context.get(name,'???') print "%10s = %18.15e (%s)\t[%s]" % (name, value, assignment, comment) else: print "%s not defined. %s" % (name, assignment) else: print line -------------------------------------------------------------------------------------------- >There are a few ways of fixing this. The easiest is to start Python up with the '-Qnew' command line option, which turns on true division globally: mumak:~ dyoo$ python -Qnew Python 2.3.5 (#1, Mar 20 2005, 20:38:20) [GCC 3.3 20030304 (Apple Computer, Inc. build 1809)] on darwin Type "help", "copyright", "credits" or "license" for more information > I'd recommend this approach: it means you won't have to change much. Unfortunately, this means that you'll have to remember to use '-Qnew' all the time, and that's bug-prone. An alternative way is to fix the bug is to modify extractEquation and evaluateEquation so that it doesn't depend on Python's evaluation functions. To an experienced programmer, I'd recommend that approach, to replace the call to 'exec' with a customized parser and evaluator: we have more control over the arithmetic. If you really need something like this, one of us can probably cook up such an evaluator for you. --------------------------------------------------------------------------------------------------- Thank you for your help! Hubert

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Need help with wxListCtrl
by Jacob S. Nov. 30, 2005

Nov. 30, 2005

Resending due to change in subject line -- adding [Tutor] Also, I wish to point out now that I've noticed, the spacing on the diagram hasn't persisted.... If anyone wants a jpg or something, let me know. > Hi, long time no see. > > For you Spanish speakers: > > Yo tenía que aprender a poco español mientras no estaba aquí. Si ustedes > son aburrido y me desean ayudar aprender más, mandan una -- ¿Qué desea > decir "email"? Y no mandan el (email) en el (mailing list), por favor. > (It would be much, much appreciated.) > > > > Okay, now that that is done, I would appreciate help with the wxListCtrl. > The documentation is supposed to be portable between languages, but it > confuses me. Using boa-constructor, I have placed a wxListCtrl on my > form, but am unable to figure out how to add items to it. Diagram below. > > > > +-----------+---------------------+--------------------+------------------+----------------+---------+ > > | Date | Description | Points | > Points Possible | Percentage | Grade | > > +-----------+---------------------+--------------------+------------------+----------------+---------+ > > | | | | > | | | > > | | | | > | | | > > | | | | > | | | > > | | | | > | | | > > | | | | > | | | > > | | | | > | | | > > | | | | > | | | > > +-----------+---------------------+--------------------+------------------+----------------+---------+ > > > I noticed there is a simplified form of wxListCtrl, but both seem to want > to add wxListItem s which include images, etc. > Does anyone know a straight forward way to add lines to this control > implicitly -- programmatically? > I figure if I don't get responses here, I will try at the wxPython list. > (I hesitate to do that yet, I know you better here) > > Sincerely, > Jacob

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Unicode trouble
by Øyvind Nov. 30, 2005

Nov. 30, 2005

Øyvind wrote: > >>Where are you getting these errors (what line of the program)? Do you > > know >what kind of strings objSelection.Find.Execute() is expecting? > >>Kent > > >> The program stops working and gives me these errors when I try to run it >> when it encounters a non-english letter. > >> This is the full error: >> Traceback (most recent call last): >> File >> "C:\Python23\Lib\site-packages\pythonwin\pywin\framework\scriptutils.py", >> line 310, in RunScript >> exec codeObject in __main__.__dict__ >> File "C:\Python\BA\Oversett.py", line 47, in ? >> File "C:\Python\BA\Oversett.py", line 23, in kjor >> en = i.split('\t')[0] >> File "C:\Python23\lib\codecs.py", line 388, in readlines >> return self.reader.readlines(sizehint) >> File "C:\Python23\lib\codecs.py", line 314, in readlines >> return self.decode(data, self.errors)[0].splitlines(1) >> UnicodeDecodeError: 'utf8' codec can't decode bytes in position 168-170: >> invalid data >This is fairly strange as the line > en = i.split('\t')[0] >should not call any method in codecs. I don't know how you can get such a >stack trace. The file f where en comes from does contain lots of lines with one english word followed by a tab and a norwegian one. (Approximately 25000 lines) It can look like this: core\tkjærne So en is supposed to be the english word that the program need to find in MS Word, and to is the replacement word. So wouldn't that be a string that should be handeled by codecs? for i in self.f.readlines(): en = i.split('\t')[0] >Maybe try deleting all the .pyc files to make sure they are in sync with >the source and try again? This didn't seem to help. >The actual error indicates that the input data is not valid utf-8. Are you >sure that is the correct encoding for the input file? If the file is utf-8 >and has bad characters you could pass error='ignore' or error='replace' as >a parameter to codecs.open() to change the error handling style to >something more forgiving. Is not valid utf-8? I have tried with latin-1 as well. No avail. The letters that are the problem is æøå. They shouldn't be that exotic? >> Traceback (most recent call last): >> File >> "C:\Python23\Lib\site-packages\pythonwin\pywin\framework\scriptutils.py", >> line 310, in RunScript >> exec codeObject in __main__.__dict__ >> File "C:\Python\BA\Oversett.py", line 49, in ? >> File "C:\Python\BA\Oversett.py", line 33, in kjor >> if t % 1000 == 0: >> UnicodeDecodeError: 'ascii' codec can't decode byte 0xe5 in position 17: >> ordinal not in range(128) >Again this stack trace doesn't make sense, the indicated line doesn't do >any string operation. >This error message normally occurs when a non-ascii string is converted to >unicode using the default encoding (which is 'ascii'). Often the >conversion is implicit in some other operation but I don't see any such >operation here. But regardless, shouldn't 'ascii' be excluded here? Since I tell the program to change to utf-8, not only once but twice? >> objSelection.Find.Execute() is supposed to accept any kind of string. (It >> is the function Search & Replace in MS Word). >It has to make some assumption about the type of the string. Does it want >unicode or encoded bytes? If encoded bytes, what encoding does it expect? I think the letters should be accepted. The pythonscript here is written to replace abot 25000 MS Word-macros, so all the letters have been accepted by MS Word when feeded by Visual Basic. All I have done now is to extract the words from the macros and put them in a file. -- This email has been scanned for viruses & spam by Decna as - www.decna.no Denne e-posten er sjekket for virus & spam av Decna as - www.decna.no

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Need help with wxListCtrl
by Jacob S. Nov. 30, 2005

Nov. 30, 2005

Hi, long time no see. For you Spanish speakers: Yo tenía que aprender a poco español mientras no estaba aquí. Si ustedes son aburrido y me desean ayudar aprender más, mandan una -- ¿Qué desea decir "email"? Y no mandan el (email) en el (mailing list), por favor. (It would be much, much appreciated.) Okay, now that that is done, I would appreciate help with the wxListCtrl. The documentation is supposed to be portable between languages, but it confuses me. Using boa-constructor, I have placed a wxListCtrl on my form, but am unable to figure out how to add items to it. Diagram below. +-----------+---------------------+--------------------+------------------+----------------+---------+ | Date | Description | Points | Points Possible | Percentage | Grade | +-----------+---------------------+--------------------+------------------+----------------+---------+ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | +-----------+---------------------+--------------------+------------------+----------------+---------+ I noticed there is a simplified form of wxListCtrl, but both seem to want to add wxListItem s which include images, etc. Does anyone know a straight forward way to add lines to this control implicitly -- programmatically? I figure if I don't get responses here, I will try at the wxPython list. (I hesitate to do that yet, I know you better here) Sincerely, Jacob

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Unicode trouble
by Øyvind Nov. 30, 2005

Nov. 30, 2005

>Where are you getting these errors (what line of the program)? Do you know >what kind of strings objSelection.Find.Execute() is expecting? > >Kent The program stops working and gives me these errors when I try to run it when it encounters a non-english letter. This is the full error: Traceback (most recent call last): File "C:\Python23\Lib\site-packages\pythonwin\pywin\framework\scriptutils.py", line 310, in RunScript exec codeObject in __main__.__dict__ File "C:\Python\BA\Oversett.py", line 47, in ? File "C:\Python\BA\Oversett.py", line 23, in kjor en = i.split('\t')[0] File "C:\Python23\lib\codecs.py", line 388, in readlines return self.reader.readlines(sizehint) File "C:\Python23\lib\codecs.py", line 314, in readlines return self.decode(data, self.errors)[0].splitlines(1) UnicodeDecodeError: 'utf8' codec can't decode bytes in position 168-170: invalid data and Traceback (most recent call last): File "C:\Python23\Lib\site-packages\pythonwin\pywin\framework\scriptutils.py", line 310, in RunScript exec codeObject in __main__.__dict__ File "C:\Python\BA\Oversett.py", line 49, in ? File "C:\Python\BA\Oversett.py", line 33, in kjor if t % 1000 == 0: UnicodeDecodeError: 'ascii' codec can't decode byte 0xe5 in position 17: ordinal not in range(128) objSelection.Find.Execute() is supposed to accept any kind of string. (It is the function Search & Replace in MS Word). -- This email has been scanned for viruses & spam by Decna as - www.decna.no Denne e-posten er sjekket for virus & spam av Decna as - www.decna.no

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rare matrix
by János Juhász Nov. 30, 2005

Nov. 30, 2005

Dear All, do you know any python solution to handle big big rare matrices effectively with python. I would make matrix multiplications with 3000x3000 matrices, but with 1-2% data in them. Could you recommend any starting point for that ? Yours sincerely, ______________________________ János Juhász

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