python

Can zlib.crc32 or zlib.adler32 be safely used to mask primary keys in URLs?

In Django Design Patterns, the author recommends using zlib.crc32 to mask primary keys in URLs. After some quick testing, I noticed that crc32 produces negative integers about half the time, which seems undesirable for use in a URL. zlib.adler32 does not appear to produce negatives, but is described as "weaker" than CRC. Is this method...

Django project models.py versus app models.py

I am learning Django and I am trying to understand the use of models.py in the project versus the application. It seems from the tutorial examples that I include a model definition in the app, but when I went to apply that knowledge to my own existing database I got stuck. I took a database that I use (a copy of course) and generated t...

Making all variables accessible to namespace

Hello, Say I have a simple function: def myfunc(): a = 4.2 b = 5.5 ... many similar variables ... I use this function one time only and I am wondering what is the easiest way to make all the variables inside the function accessible to my main name-space. Do I have to declare global for each item? or any other suggested ...

Any tips on moving from ActionScript 3 to Python?

I've been developing stuff using ActionScript since AS2,and when AS3 was released i had a bit of a hard time to understand its concepts. Then i realized i had to learn some OOP. I started studying OOP and now i feel i need to take a step further, that's why i chose Python. Are there any tips/advices/hints or whatever like that to help me...

How do I write raw binary data in Python?

I've got a Python program that stores and writes data to a file. The data is raw binary data, stored internally as str. I'm writing it out through a utf-8 codec. However, I get UnicodeDecodeError: 'charmap' codec can't decode byte 0x8d in position 25: character maps to <undefined> in the cp1252.py file. This looks to me like Python i...

Quickest way to dump Python dictionary (dict) object to a MySQL table?

I have a dict object. I dumped the data using this: for alldata in data: # print all data to screen print data[alldata] Each field had brackets [] and 'None' values for NULLS and date.datetime for date values. How do I dump this dict to MySQL table? Thank you! print data displays something like this : {'1': ['1', 'K', abc, 'xyz...

working on lists in python

'm trying to make a small modification to django lfs project, that will allow me to deactivate products with no stocks. Unfortunatelly I'm just beginning to learn python, so I have big trouble with its syntax. That's what I'm trying to do. I'm using method 'is_variant' returning tru if my product is a sub type. If it is a variant I'm tur...

Pylons custom authorizer with Authkit?

how do i setup authkit for more authorizer? i want to give certain users admin rights, but only for their own page. thanks ...

Installing Python Script, Maintaining Reference to Python 2.6

Hi, I am trying to distribute my Python program. The program relies on version 2.6. I went through the distribution documentation: http://docs.python.org/distutils/index.html and what I have figured out so far is that I basically need to write a setup.py script. Something like: setup(name='Distutils', version='1.0', description='Py...

SQLAlchemy: who is in charge of the "session"? ( and how to unit-test with sessions )

I need some guidance on how to use session objects with SQLAlchemy, and how to organize Unit Tests of my mapped objects. What I would like to able to do is something like this: thing = BigThing() # mapped object child = thing.new_child() # create and return a related object thing.save() # will also save the child object In order to a...

How to use the _Qt python module?

There is a python module called "_Qt". PyQt is not what I want. I was wondering if there was any documentation for the _Qt module installed with python as a standard module. I have a mac. ...

Geometry library for python (or C++) for CAD-like operations?

I'm trying to put together a simple program that will let me visualize a series of consecutive cuts on a wood panel using a router with a particular cutting head. I'm trying to find a decent geometry library that will give me a shortcut through the CAD-like stuff. Specifically, I'd like to be able to define a rectangular solid (the w...

PGU Tiles collision detection

Hi, I've been using PGU(Phil's Pygame Utilities) for a while. It has a dictionary called tdata, which is passed as an argument while loading tiles tdata = { tileno:(agroup, hit_handler, config)} I'm making a pacman clone in which I have 2 groups : player and ghost, for which I want to collision detection with the same type of tile. Fo...

struct.error: unpack requires a string argument of length 4

Python says I need 4 bytes for a format code of "BH": struct.error: unpack requires a string argument of length 4 Here is the code, I am putting in 3 bytes as I think is needed: major, minor = struct.unpack("BH", self.fp.read(3)) "B" Unsigned char (1 byte) + "H" Unsigned short (2 bytes) = 3 bytes (!?) struct.calcsize("BH") says 4 ...

Rationale behind Python's preferred for syntax

What is the rationale behind the advocated use of the for i in xrange(...)-style looping constructs in Python? For simple integer looping, the difference in overheads is substantial. I conducted a simple test using two pieces of code: File idiomatic.py: #!/usr/bin/env python M = 10000 N = 10000 if __name__ == "__main__": x, y = 0...

get python class parent(s)

How can I get the parent(s) object of python class? ...

Python Desktop Application with the Browser as an interface?

I want to create an application that runs on the users computer, a stand-alone application, with installation and what-not, but I want the interface to be a browser, either internal and displayed as an OS window or external accessible using the browser (i.e. some http server). The reason would be because I know a little about Python, bu...

Python: Is there a way to reflectivly list all attributes of a class

Given a class such as class MyClass: text = "hello" number = 123 Is there a way in python to inspect MyClass an determine that it has the two attributes text and number. I can not use something like inspect.getSource(object) because the class I am to get it's attributes for are generate using SWIG (so they are hidden in .so :)...

convert RGB values to equivalent HSV values using python

Hi, I want to convert RGB values to HSV using python. I got some code samples, which gave the result with the S and V values greater than 100. (example : http://code.activestate.com/recipes/576554-covert-color-space-from-hsv-to-rgb-and-rgb-to-hsv/ ) . anybody got a better code which convert RGB to HSV and vice versa thanks ...

Installing a python wrapper for a c++ library

Hi all, I am trying to install the python wrapper for the ANN (approx near neighbors) c++ library: link is http://www.scipy.org/scipy/scikits/wiki/AnnWrapper . I am on Windows 7 32-bit. Unfortunately the documentation is a bit terse and I am a newbie to programming in general, so I cannot decipher the instructions found within. I hav...