question about slicing with a step length

[James Stroud]

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]?
> 
> I thought the first index, whether going forward or backward, was 
> inclusive. And there is no index of 10 in this list, so what is it 
> referring to?
> 
> Thanks.

Its referring to right after the end of the list, just as the 0 refers 
to just before the start of the list. The word "slice" is supposed to 
suggest cutting between (or before or after) elements.

-- 
James Stroud
UCLA-DOE Institute for Genomics and Proteomics
Box 951570
Los Angeles, CA 90095

http://www.jamesstroud.com/