Tino Dai wrote: > Hi Everybody, > > Thank you so much for the information on sets. I think that that > has certain uses, but in my case I can't find a way. I have been > thinking about sequences in a list. Let me give you an example: > > tset = [ 1,2,4,0,0,1,2,4,4] > > What I want to do is detect the 1,2,4 sequence and perhaps how many.
There is nothing built-in for this. Here is a solution that uses index() to quickly find potential starting points. It is based on this post to c.l.py and the followup: http://groups.google.com/group/comp.lang.python/msg/a03abee619ec54ef?hl=en&; This is likely to be much faster than Lutz' solution tset is long, though you would have to test to be sure. def subPositions(alist, innerlist): if innerlist == []: return first, start = innerlist[0], 0 while 1: try: p = alist.index(first, start) except ValueError: return if alist[p: p + len(innerlist)] == innerlist: yield p start = p+1 Kent _______________________________________________ Tutor maillist - [email protected] http://mail.python.org/mailman/listinfo/tutor
