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Re: Newbie questions on Python

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When slicing: l[start:end:step]

In your example of "a[2::-1]" you are reversing the list by using a step of
-1, then you are slicing at index 2 (third element).

*Matt Jones*


On Tue, Apr 16, 2013 at 10:30 AM, Chris Angelico <rosuav@gmail.com> wrote:

> On Wed, Apr 17, 2013 at 1:20 AM,  <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]
> >
> > what does a[2::-1] means?
>
> That's taking a slice. This page has something to say on the subject:
>
> http://docs.python.org/3.3/tutorial/introduction.html
>
> By the way, regarding your email address: there are no cheat codes in
> Python... either that, or Python *is* a cheat code. :)
>
> ChrisA
> [[ VERY HAPPY CODING ADDED ]]
> --
> http://mail.python.org/mailman/listinfo/python-list
>

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Thread

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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