Difference between revisions of "Python"

Revision as of 17:28, 20 November 2009

HRL Coding Standards

• In general, we follow the official python coding standards (Python standards) but we will summarize here the relevant key points.
  • Every indent is 4 spaces, replace all tabs with spaces.
  • ClassName, method_name, _private_name
  • Use classes sparingly, please try to define functions whenever possible.
  • Instead of using inheritance, use duck typing (i.e. define interfaces based on conventions)
  • With numpy, use matrices instead of arrays, all vectors should be column vectors.
  • We use doxygen styled comments:

 ##
 # some comments
 # @param a is 3x1 point in coordinate frame C
 # @param b is a 3x3 rotation matrix
 # @return a 3x1 vector rotated by b
 def my_function(a, b):
     return b*a

learning python

• http://docs.python.org/
• http://docs.python.org/library/index.html
• python for programmers
• guido's guide (http://docs.python.org/tut/)
• dive into python (book) (http://www.diveintopython.org/toc/index.html)
• quick reference (http://rgruet.free.fr/PQR25/PQR2.5.html)
• ipython (http://ipython.scipy.org/moin/)

math, science, numerical, etc.

• numpy (http://numpy.scipy.org/)
• scipy (http://scipy.org/)
• matplotlib (http://matplotlib.sourceforge.net/): in ipython shell
• mayavi (http://code.enthought.com/projects/mayavi/)

opencv

• python specific documentation: PythonInterface, SWIG Python Interface

efficiency

• When you need buffering of some sort for logging/writing data, if speed is important use the deque data structure instead of lists: http://docs.python.org/library/collections.html#collections.deque