🌐 Mailman 3 September 2009 - Python-list - python.org

ANN: pygene - genetic algorithms package
by aum Aug. 22, 2016

Aug. 22, 2016

Hi all, I looked at a few genetic algorithms/genetic programming packages for Python, and found them somewhat convoluted, complicated and counter-intuitive to use. So I've written a genetic algorithms package which I hope will be more approachable to beginners. The first release of pygene is up at: http://www.freenet.org.nz/python/pygene The package includes full api documentation, and an implementation of the travelling salesman problem, plus a couple of simpler cases. -- Cheers aum

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cx_Oracle + array parameter
by lukasz.f24＠gmail.com March 4, 2016

March 4, 2016

Hello, I'm trying to pass array as an argument into PL/SQL procedure. According to cursor manual (http://cx-oracle.sourceforge.net/html/ cursorobj.html) arrayvar() should be use to do it. I've created my array type in PL/SQL: CREATE OR REPLACE TYPE cx_array_string is table of varchar2(200); and simple procedure: CREATE OR REPLACE PROCEDURE text(ret IN cx_array_string) IS BEGIN null; END text; My python code: p_array = curs.arrayvar(cx_Oracle.STRING, ['1','3']) curs.execute('BEGIN text( :1 ); end;', [p_array] ) And it gives me back an error: cx_Oracle.DatabaseError: ORA-06550: line 1, column 7: PLS-00306: wrong number or types of arguments in call to 'TEXT' ORA-06550: line 1, column 7: PL/SQL: Statement ignored It's the same when i try to use callproc() instead of execute(). I've searched whole internet with no luck. Could anyone please give me a working example python + pl/sql how to pass string array form py to oracle procedure, please. Thank you!

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Re: convert Dbase (.dbf) files to SQLite databases
by John Machin March 1, 2016

March 1, 2016

On Jul 15, 8:39 pm, David Lyon <david.l...(a)preisshare.net> wrote: > On Wed, 15 Jul 2009 11:53:28 +0200, Helmut Jarausch > > <jarau...(a)igpm.rwth-aachen.de> wrote: > > Hi, > > > I have a lot of old Dbase files (.dbf) and I'll like to convert these > > to SQLite databases as automatically as possible. > > Does anybody know a tool/Python script to do so? > > > I know, I could use dbfpy and create the SQLite table and import all > > data. But is there something easier? > > yes... > > Use OpenOffice-Scalc or MS-Office-Excel to open the table... Max 64K rows for Scalc and Excel 2003; 2007 can take 2**20 rows. Only old dBase (not dBase 7). Memo fields not handled. Visual FoxPro DBFs not supported by Excel even tho' VFP is an MS product. > Export to csv.... Yuk. > > Use SQLite Manager (https://addons.mozilla.org/en-US/firefox/addon/5817) > > and use the import wizard to import your data.... > > It shouldn't take too long... ... before you get sick of the error-prone manual tasks. I'd write a script that took a DBF file, analysed the field descriptions, made a CREATE TABLE statement, executed it, and then started doing inserts. Fairly easy to write. Scripts have the great benefit that you can fix them and re-run a whole lot easier than redoing manual steps. If dbfpy can't handle any new-fangled stuff you may have in your files, drop me a line ... I have a soon-to-be released DBF module that should be able to read the "new" stuff up to dBase7 and VFP9, including memo files, conversion from whatever to Unicode if needed, ... Cheers, John

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How to get all IP addresses in python?
by Yun Mao Feb. 25, 2016

Feb. 25, 2016

Hi. I did a little homework on google for this question. The answer was: >>> import socket >>> hostname = socket.gethostname() >>> ip = socket.gethostbyname(hostname) >>> print ip 192.168.55.101 But what if I have several interfaces, say eth0, eth0:1, eth1, etc. How to get all of them? It would be a little undesirable if people suggest to parse the result of ifconfig because I in particular want the code to be cross platform. Thanks a lot! Yun

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Best programs written completly in Python
by Franz Steinh�usler Feb. 12, 2016

Feb. 12, 2016

Hello NG, wWhat are the best programs in your opinion, written entirly in pyhton, divided into categories like: a) Games b) Utilities/System c) Office d) Web/Newsreader/Mail/Browser ... I don't want to start a long thread, if a site of such an discussion already exists, a link will be enough. Many thanks in advance! -- Franz Steinhaeusler

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Script to extract text from PDF files
by brad Nov. 6, 2015

Nov. 6, 2015

I have a very crude Python script that extracts text from some (and I emphasize some) PDF documents. On many PDF docs, I cannot extract text, but this is because I'm doing something wrong. The PDF spec is large and complex and there are various ways in which to store and encode text. I wanted to post here and ask if anyone is interested in helping make the script better which means it should accurately extract text from most any pdf file... not just some. I know the topic of reading/extracting the text from a PDF document natively in Python comes up every now and then on comp.lang.python... I've posted about it in the past myself. After searching for other solutions, I've resorted to attempting this on my own in my spare time. Using apps external to Python (pdftotext, etc.) is not really an option for me. If someone knows of a free native Python app that does this now, let me know and I'll use that instead! So, if other more experienced programmer are interested in helping make the script better, please let me know. I can host a website and the latest revision and do all of the grunt work. Thanks, Brad

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Einstein's Riddle
by Steve Graham Sept. 17, 2015

Sept. 17, 2015

Who would be interested in using his/her brain (and his computer) to solve the following? Steve Graham === Einstein's Riddle Albert Einstein wrote this riddle this century [ed. 20th century]. He said 98% of the world could not solve it. There are 5 houses in 5 different colors. In each house lives a person with a different nationality. The 5 owners drink a certain type of beverage, smoke a certain brand of cigar, and keep a certain pet. No owners have the same pet, smoke the same brand of cigar or drink the same beverage. The question is: "Who owns the fish?" Hints: The Brit lives in the red house. The Sweed keeps dogs as pets. The Dane drinks tea. The green house is on the left of the white house. The green house's owner drinks coffee. The person who smokes Pall Mall rears birds. The owner of the yellow house smokes Dunhill. The man living in the center house drinks milk. The Norwegian lives in the first house. The man who smokes Blends lives next to the one who keeps cats. The man who keeps the horse lives next to the man who smokes Dunhill. The owner who smokes Bluemasters drinks beer. The German smokes Prince. The Norwegian lives next to the blue house. The man who smokes Blends has a neighbor who drinks water.

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Confessions of a Python fanboy
by r May 11, 2015

May 11, 2015

Hello fellow Pythonista's it's nice to be back after such a long hiatus. I have recently realized my blind love affair with Python was just that. I must admit there are better ways to program. Like your first lay, your first programing language can leave an indelible mark on you, but like all young chaps, the passion for programming has sweep me away into vast new orgies of programming bliss. (ig ,little head guides the big one.) My adventures in Ruby. an autobyography by rt8396 After breaking free from the wild love affair i had with Python, a new day had dawned. I dried my eyes and soon discovered the Ruby language (not by choice however) --now don't worry fellow Pythonistas, i am still on your side (mostly) -- but i now realize Ruby has some good things going for it. For instance... 1.) No need to use "()" to call a function with no arguments. Python --> "obj.m2().m3()" --ugly Ruby --> "obj.m1.m2.m3" -- sweeet! Man, i must admit i really like this, and your code will look so much cleaner. 2.) the .each method container.each{|localVar| block} This method can really cleanup some ugly for loops, although i really like the readability of for loops. 3.) true OOP Now before you go and get all "huffy" over this statement, hear me out. Python is the best language in the world. But it damn sure has some warts! "len(this)" instead of "obj.length" max(that) instead of [1,2,3,4,5].max(). You know what i am talking about here people. We all get complacent and It seems easier to just cope with these problems instead of fighting for change. But look at the French, WHAT THE HELL HAS THAT DONE FOR THEM, *NOTHING*!!!! As for the rest of Ruby, i am not impressed. The redundant usage of "end" over indention perplexes me. The Perlish feel of "require" and the horrifically cryptic idioms of Ruby regular expressions. The "puts" and "gets" seem childish and the math class does not even have a degrees or radians function! Anyway, i thought i would get this off my chest and catch up with old friends in the meantime. We can all make Python the perfect language it needs to be, but it ain't gonna be easy! Thank you all PS stay tuned for more from this series....

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How to receive a data file of unknown length using a python socket?
by twgray April 22, 2015

April 22, 2015

I am attempting to send a jpeg image file created on an embedded device over a wifi socket to a Python client running on a Linux pc (Ubuntu). All works well, except I don't know, on the pc client side, what the file size is? The following is a snippet: [code] f = open("frame.jpg",mode = 'wb') while True: data = self.s.recv(MAXPACKETLEN) if len(data) == 0: break recvd += len(data) f.write(data) f.close() [end] It appears to be locking up in 'data=self.s.recv(MAXPACKETLEN)' on the final packet, which will always be less than MAXPACKETLEN. I guess my question is, how do I detect end of data on the client side?

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Python to C++ in a pickle
by Larry Whitley April 2, 2015

April 2, 2015

I'd like to pickle an object in python and unpickle it in C++. The object in question is a python dictionary so it will have to go into a C++ map. Has someone done this and is willing to share? Or, is the cPickle source available on the web somewhere? Larry

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