In <ig1u77$4iv$0...@news.t-online.com> Peter Otten <__pete...@web.de> writes:
>ana sanchez wrote: >> i found this when i read the source of a program in python: >> >> self.__chunks[start:end] = (chunk for i in xrange(start, end)) >> what utility has to assign a generator to a slice??? ?the *final >> result* isn't the same as this?: >> >> self.__chunks[start:end] = [chunk for i in xrange(start, end)] >Whoever used the first variant probably was hoping that it was either faster >or used less peak memory. I think the latter is wrong, and the former can >easily be checked: >$ python -m timeit -s'chunk = "yadda"; chunks = range(100); start = 20; end >= 50' 'chunks[start:end] = (chunk for i in xrange(start, end))' >100000 loops, best of 3: 9.02 usec per loop >$ python -m timeit -s'chunk = "yadda"; chunks = range(100); start = 20; end >= 50' 'chunks[start:end] = [chunk for i in xrange(start, end)]' >100000 loops, best of 3: 4.16 usec per loop >$ python -m timeit -s'chunk = "yadda"; chunks = range(100); start = 20; end >= 50' 'chunks[start:end] = [chunk]*(end-start)' >1000000 loops, best of 3: 1.02 usec per loop peter thank you very much!!! (i like very much the timing "miniscripts") ana -- http://mail.python.org/mailman/listinfo/python-list
