Am 22.08.2011 01:25, schrieb Andreas Löscher: > It's not as bad as you think. The addition of two integers is a cheap > task (in terms of computation power). If you have two way's to to it, > every little think (jumps in the code etc. ) will have a larger impact > on the execution time than on an expensive operation. > > But every improvement on your algorithm will easily result in a > significant shorter execution time than replaceing a+=1 with a=a+1 will > ever do. :-)
You can learn an important lesson here. Since Python is a high level language without a JIT (yet) integer operations are much slower than in C or other low level languages. In general it's not a problem for most people. However if your algorithm is speed bound to integer operations or has a tight inner for loop than you can gain a considerable amount of speedup with C code. Reference counting and Python object creation need several CPU cycles. Also a good algorithm and a modern C compiler can make use of SIMD instructions, too. If you ever feel the need to implement something fast e.g. an encryption algorithm then you'd better off with a C implementation. Cython is my favourite tool for the job. Christian -- http://mail.python.org/mailman/listinfo/python-list
