On 09/06/2012 09:30 PM, jimbo1qaz wrote: > On Thursday, September 6, 2012 5:01:12 PM UTC-7, jimbo1qaz wrote: >> Is it faster to use bitshifts or floor division? And which is better, & or %? >> >> All divisors and mods are power of 2, so are binary operations faster? And >> are they considered bad style? > OK, I decided to change my code. Which raises a similar question: Which one > is better for setting a bit of a byte: |= or +=, assuming each will only be > run once? Intuitively, I think |=, but some timeits are inconclusive, mainly > because I don't know how it works.
Maybe i should have been clearer in my message. i don't think you'll find a meaningful difference unless you're doing longs of a few hundred digits. So if the algorithm is to OR on a bit, please use a |= augmented assignment. not only will it ward off probable bugs when you accidentally try to set the bit a second time, but it reads better for the reader of the program. The reader is more important than the compiler. -- DaveA -- http://mail.python.org/mailman/listinfo/python-list
