I have a set that i iterate over... but each time through it i would like to alternate between the original set and a variation of the set that has one of the members of the set altered (by + or - 1)
So if my original set is: [0, 2, 4, 5, 7, 9, 11] I would use that the first pass but on the second pass i might like the third member (4,) to become 3, (-1) resulting in : [0, 2, 3, 5, 7, 9, 11] But then back again to the original on the next pass (+1 back to 4,): [0, 2, 4, 5, 7, 9, 11] and then back: [0, 2, 3, 5, 7, 9, 11] again, etc. in other words i would like to alternate members of the set back and forth. Usually only 1 (or sometimes 2,) member at time. i could also imagine a needing(alter one, alter another, undo that, undo the first back to the original set): [0, 2, 4, 5, 7, 9, 11] --> [0, 2, 3, 5, 7, 9, 11] --> [0, 2, 3, 5, 7, 8, 10] --> [0, 2, 3, 5, 7, 9, 11] --> [0, 2, 4, 5, 7, 9, 11] or: original --> [0, 2, 4, 5, 7, 9, 11] altered --> [0, 2, 3, 5, 7, 9, 11] now back to 4, but change something else (like 11, is now 10): [0, 2, 4, 5, 7, 9, 10] etc... How can one make such alternating patterns? -kp-- _______________________________________________ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
