On 16 January 2013 21:54, Abhishek Pratap <abhishek....@gmail.com> wrote: > Hi Guys > > With the help of an awesome python community I have been able to pick up the > language and now willing to explore other cool extensions of it.
Good work! > > I routinely have large loops which could be ported to cython for speed. > However I have never written a single line of cython code. Any pointers on > getting started. There are two reasons for using cython: 1) To interface directly with existing C libraries. 2) To speed up CPU-intensive code. It sounds like you're interested in case 2). However, not all loops benefit from cythonisation. Loosely cython is good when a) you're doing something that can be written in a small amount of efficient C code b) but the corresponding Python code involves a lot of repeated function calls or expression evaluations. If you're already familiar with C then you'll probably have some idea when a) and b) apply. I would say that a prerequisite for learning to speed up CPU-intensive code with cython would be learning to use the python profilers. In particular you should learn to use cProfile and timeit: http://docs.python.org/2/library/profile.html http://docs.python.org/2/library/timeit.html As with any optimisation it is important to study the performance of your code and identify bottlenecks first. It is also generally true that you should (at least) consider algorithmic optimisation before you consider using something like cython for micro-optimisation. One of the guiding principles in the design of the Python language is that big-O complexity is often more important than micro-optimisation. Similarly, you should normally try to optimise and benchmark your code in pure Python before attempting to improve on that with cython. > > A tutorial text or video would be of great help. Here is the official "basic tutorial" for cython: http://docs.cython.org/src/userguide/tutorial.html There are also lots of helpful people on the cython-users mailing list: https://groups.google.com/forum/?fromgroups#!forum/cython-users If you have a particular problem in mind that might benefit from cythonisation, then why not post (a shortened but complete version of) it here to see if anyone has any pointers about how to improve the performance with/without cython. Oscar _______________________________________________ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
