On Wed, Apr 06, 2005 at 03:30:41PM -0700, RickMuller wrote: > I have to sort a list, but in addition to the sorting, I need to > compute a phase factor that is +1 if there is an even number of > interchanges in the sort, and -1 if there is an odd number of > interchanges. >
<snip> I would just write a quicksort and have a counter in the swap function. A cunning way to do it would be to multiply the counter by -1 for each swap. if you want I can write what I had in mind. Wikipedia has a good article of quicksort. Pete -- http://mail.python.org/mailman/listinfo/python-list
