list IndexError

Steve Holden steve at holdenweb.com
Thu Dec 23 10:16:02 EST 2004


M.E.Farmer wrote:

> Hello Ishwor ,
> The simpliest way I can explain slicing is that the slices point to the
> spot *between* the items......
> Take this list for example
> slicer =  [0,1,2,3,4,5]
> 
>>>>slicer [1]
> 
> 1
> 
>>>>slicer [1:2]
> 
> [1]
> 
>>>>slicer [:-1]
> 
>  [0,1,2,3,4] 
> 
>>>>slicer[2,4]
> 
> [2,3]
> 
You can also use a "stride" rather than take every element and (in 
recent Pythons) go backwards:

Python 2.4 (#1, Dec  4 2004, 20:10:33)
[GCC 3.3.3 (cygwin special)] on cygwin
Type "help", "copyright", "credits" or "license" for more information.
  >>> slicer = [0,1,2,3,4]
  >>> slicer[::2]
[0, 2, 4]
  >>> slicer[1::2]
[1, 3]
  >>> >>> slicer[::-1]
[4, 3, 2, 1, 0]
  >>> slicer[-1::-2]
[4, 2, 0]
  >>>

regards
  Steve
-- 
Steve Holden               http://www.holdenweb.com/
Python Web Programming  http://pydish.holdenweb.com/
Holden Web LLC      +1 703 861 4237  +1 800 494 3119



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