On Fri, 24 Mar 2006 15:40:17 +0100, "Diez B. Roggisch" <[EMAIL PROTECTED]> wrote: >Tim N. van der Leeuw wrote: >> I also wonder if it wouldn't be faster to put the numbers into a list >> and join the list into a string -- did you test with that? > >It will be faster - the naive string concatenation is quadratic, whereas the >list-based approach is linear.
It won't be any faster in CPython 2.4 or newer. This kind of string concatenation is optimized so as to be linear: $ python -m timeit -s "x = ''" "for i in xrange(1000): x += 'x'" 1000 loops, best of 3: 335 usec per loop $ python -m timeit -s "x = ''" "for i in xrange(10000): x += 'x'" 100 loops, best of 3: 3.35 msec per loop $ python -m timeit -s "x = ''" "for i in xrange(100000): x += 'x'" 10 loops, best of 3: 33.2 msec per loop $ python -m timeit -s "x = ''" "for i in xrange(1000000): x += 'x'" 10 loops, best of 3: 347 msec per loop $ python -m timeit -s "x = ''" "for i in xrange(10000000): x += 'x'" 10 loops, best of 3: 3.48 sec per loop $ Jean-Paul -- http://mail.python.org/mailman/listinfo/python-list
