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Re: Newbie questions on Python

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On 2013-04-16, idkfaidkfaidkfa@gmail.com <idkfaidkfaidkfa@gmail.com> wrote:
> Hi all,
> i'm programming in python for the first time (usually i use C as programming language). I don't understand these results:
>
>>>> a=[1,2,3,4,5]
>>>> a[:-1]
> [1, 2, 3, 4]
>>>> a[::-1]
> [5, 4, 3, 2, 1]
>>>> a[2::-1]
> [3, 2, 1]

The third item is the "step". The default value is 1. If you
provide a negative step, your slice will be in reverse. So you
are getting item 2 through 0 in reverse order in your result
slice.

Imagine something like the following for loop taking place
somewhere:

for (int i = 2; i <= 0; --i) {
    fprintf(a[i]);
}
   
-- 
Neil Cerutti

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Newbie questions on Python idkfaidkfaidkfa@gmail.com - 2013-04-16 08:20 -0700
  Re: Newbie questions on Python Chris Angelico <rosuav@gmail.com> - 2013-04-17 01:30 +1000
    Re: Newbie questions on Python Walter Hurry <walterhurry@lavabit.com> - 2013-04-16 21:40 +0000
      Re: Newbie questions on Python Chris Angelico <rosuav@gmail.com> - 2013-04-17 07:53 +1000
  Re: Newbie questions on Python Matt Jones <matt.walker.jones@gmail.com> - 2013-04-16 10:33 -0500
  Re: Newbie questions on Python Neil Cerutti <neilc@norwich.edu> - 2013-04-16 15:41 +0000
    Re: Newbie questions on Python Lele Gaifax <lele@metapensiero.it> - 2013-04-16 18:06 +0200
      Re: Newbie questions on Python Neil Cerutti <neilc@norwich.edu> - 2013-04-16 17:16 +0000

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