python

Regex for [a-zA-Z0-9\-] with dashes allowed in between but not at the start or end

Update: This question was an epic failure, but here's the working solution. It's based on Gumbo's answer (Gumbo's was close to working so I chose it as the accepted answer): Solution: r'(?=[a-zA-Z0-9\-]{4,25}$)^[a-zA-Z0-9]+(\-[a-zA-Z0-9]+)*$' Original Question (albeit, after 3 edits) I'm using Python and I'm not trying to extract t...

Speex in Python

How can I use Speex to encode/decode from within python? Are there any wrappers? I found an old project pySpeex but it is obsolete now (requires Python 2.2). ...

Writing code translator from Python to C?

I was asked to write a code translator that would take a Python program and produce a C program. Do you have any ideas how could I approach this problem or is it even possible? Thanks, Boda Cydo. ...

Matching first set of elements with xpath...

I have an xml document that looks like this. <foo> <bar type="artist"/> Bob Marley </bar> <bar type="artist"/> Peter Tosh </bar> <bar type="artist"/> Marlon Wayans </bar> </foo> <foo> <bar type="artist"/> Bob Marley </bar> <bar type="artist"/> Peter Tosh </bar> <bar type="artist"/> Marlon Wayans </bar> </foo> <fo...

Twisted - how to create multi protocol process and send the data between the protocols

Hey, Im trying to write a program that would be listening for data (simple text messages) on some port (say tcp 6666) and then pass them to one or more different protocols - irc, xmpp and so on. I've tried many approaches and digged the Internet, but I cant find easy and working solution for such task. The code I am currently fighting ...

How to write the Visitor Pattern for Abstract Syntax Tree in Python?

My collegue suggested me to write a visitor pattern to navigate the AST. Can anyone tell me more how would I start writing it? As far as I understand, each Node in AST would have visit() method (?) that would somehow get called (from where?). That about concludes my understanding. To simplify everything, suppose I have nodes Root, Expr...

How to best design a date/geographic proximity query on GAE?

Hi all, I'm building a directory for finding athletic tournaments on GAE with web2py and a Flex front end. The user selects a location, a radius, and a maximum date from a set of choices. I have a basic version of this query implemented, but it's inefficient and slow. One way I know I can improve it is by condensing the many individual ...

(interactive) graph as in graph theory on a web page ?

Hi, I have to integrate a graph with nodes and edges on a web page. Ideally, i would like to be able to interact with it (like moving the nodes around). Actually, i'm beginning by representing trees, so i would appreciate to be able to collapse subtrees. How can I do that ? I was considering google-visualization api but i wasn't able ...

Proper way in Python to raise errors while setting variables

What is the proper way to do error-checking in a class? Raising exceptions? Setting an instance variable dictionary "errors" that contains all the errors and returning it? Is it bad to print errors from a class? Do I have to return False if I'm raising an exception? Just want to make sure that I'm doing things right. Below is some...

Game login authentication and security.

First off I will say I am completely new to security in coding. I am currently helping a friend develop a small game (in Python) which will have a login server. I don't have much knowledge regarding security, but I know many games do have issues with this. Everything from 3rd party applications (bots) to WPE packet manipulation. Consider...

Settings module not found deploying django on a shared server

I'm trying to deploy my django project on a shared hosting as describe here I have my project on /home/user/www/testa I'm using this script #!/usr/bin/python import sys, os sys.path.append("/home/user/bin/python") sys.path.append('/home/user/www/testa') os.chdir("/home/user/www/testa") os.environ['DJANGO_SETTINGS_MODULE'] = "set...

Creating a "less"-like console pager interface for pysqlite3 database

I would like to add some interactive capability to a python CLI application I've writen that stores data in a SQLite3 database. Currently, my app reads-in a certain type of file, parses and analyzes, puts the analysis data into the db, and spits the formatted records to stdout (which I generally pipe to a file). There are on-the-order-...

pyInotify performance

I have a very large directory tree I am wanting pyInotify to watch. Is it better to have pyInotify watch the entire tree or is it better to have a number of watches reporting changes to specific files ? Thanks ...

Django ModelFormSet with Google app engine

I'm using Django with google app engine. I'm using the google furnished django app engine helper project. I'm attempting to create a Django modelformset like this: #MyModel inherits from BaseModel MyFormSet = modelformset_factory(models.MyModel) However, it's failing with this error: 'ModelOptions' object has no attribute 'fi...

Error handling with Python + Pylons

What is the proper way to handle errors with Python + Pylons? Say a user sets a password via a form that, when passed to a model class via the controller, throws an error because it's too short. How should that error be handled so that an error message gets displayed on the web page rather than the entire script terminating to an error...

Python Permutation Program Flow help

Hello world, i found this code at activestate, it takes a string and prints permutations of the string. I understand that its a recursive function but i dont really understand how it works, it'd be great if someone could walk me through the program flow, thanks a bunch! import sys def printList(alist, blist=[]): if not len(alist): ...

Forwarding keypresses in GTK

I'm writing a bit of code for a Gedit plugin. I'm using Python and the interface (obviously) is GTK. So, the issue I'm having is quite simple: I have a search box (a gtk.Entry) and right below I have a results box (a gtk.TreeView). Right after you type something in the search box you are presented a bunch of results, and I would like th...

Compiling a Python binding on Linux

Hi I'm trying to compile a Python binding, but I'm unable to find the python.h header on debian. Which package should I install? Thanks in advance ...

I need a simple command line program to transform XML using an XSL Stylesheet

I am on OSX Snow Leopard (10.6.2) I can install anything I need to. I would preferably like a Python or Java solution. I have searched on Google and found lots of information on writing my own program to do this, but this is a just a quick and dirty experiment so I don't want to invest a lot of time on writing a bunch of code to do this,...

Moon / Lunar Phase Algorithm

Does anyone know an algorithm to either calculate the moon phase or age on a given date or find the dates for new/full moons in a given year? Googling tells me the answer is in some Astronomy book, but I don't really want to buy a whole book when I only need a single page. Update: I should have qualified my statement about googling a ...