Alex Martelli wrote: > In terms of performance, however, the simple loop that you (rhamph) > posted is generally best -- e.g., with Python 2.5c1 on a MacbookPro: > > brain:~/downloads alex$ python -mtimeit -s'deep=[range(9)]*9' > 's=sum(deep,[])' > 100000 loops, best of 3: 11.2 usec per loop > > brain:~/downloads alex$ python -mtimeit -s'deep=[range(9)]*9' 's=[] >> for sublist in deep: s.extend(sublist)' > 100000 loops, best of 3: 6.92 usec per loop
at least on this machine, map(s.extend) is slightly faster than the loop: timeit -s"deep=[range(9)]*9" "s=[]" "for sublist in deep: s.extend(sublist)" 100000 loops, best of 3: 5.59 usec per loop timeit -s"deep=[range(9)]*9" "s=[]" "map(s.extend, deep)" 100000 loops, best of 3: 5.26 usec per loop </F> -- http://mail.python.org/mailman/listinfo/python-list