> John Salerno wrote: >> Given: > > numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] > > can someone explain to me why > > numbers[10:0:-2] results in [10, 8, 6, 4, 2]?
It appears that s[i:j:-1] is s[(j+1):(i+1)] .reverse()'ed. For 'numbers', this is 10, 9, 8, 7, 6, 5, 4, 3, 2]. Then take every other item. Why the +1? Don't know and not my intuitive expectation. I just know that extended slicing was developed for and until recently pretty much restricted to numeric (now numpy). Steven D'Aprano > I think the documentation is misleading/incomplete when > it comes to negative strides for extended slices. and Andre "Agreed!" also, and you three aren't the only ones. Maybe some day I will read the source, think about it more, and post a suggested revision for comment ... or maybe someone will beat me to it. Terry Jan Reedy -- http://mail.python.org/mailman/listinfo/python-list