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Re: filter a list of strings

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From Peter Pearson <pkpearson@nowhere.invalid>
Newsgroups comp.lang.python
Subject Re: filter a list of strings
Date 5 Dec 2015 19:42:04 GMT
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On Thu, 3 Dec 2015 10:27:19 +0100, <c.buhtz@posteo.jp> wrote:
[snip]
> I often saw constructions like this
>   x for x in y if ...
> But I don't understand that combination of the Python keywords (for,
> in, if) I allready know. It is to complex to imagine what there really
> happen.

Don't give up!  List comprehensions are one of the coolest things
in Python.  Maybe this simple example will make it click for you:

>>> [x**2 for x in [1,2,3,4] if x != 2]
[1, 9, 16]

-- 
To email me, substitute nowhere->runbox, invalid->com.

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Thread

filter a list of strings <c.buhtz@posteo.jp> - 2015-12-03 02:15 +0100
  Re: filter a list of strings Jussi Piitulainen <harvesting@is.invalid> - 2015-12-03 08:32 +0200
    Re: filter a list of strings <c.buhtz@posteo.jp> - 2015-12-03 10:27 +0100
      Re: filter a list of strings Jussi Piitulainen <harvesting@is.invalid> - 2015-12-03 13:53 +0200
      Re: filter a list of strings Peter Pearson <pkpearson@nowhere.invalid> - 2015-12-05 19:42 +0000
    Re: filter a list of strings Chris Angelico <rosuav@gmail.com> - 2015-12-03 20:40 +1100
    Re: filter a list of strings Wolfgang Maier <wolfgang.maier@biologie.uni-freiburg.de> - 2015-12-03 10:46 +0100
    Re: filter a list of strings Laura Creighton <lac@openend.se> - 2015-12-03 10:53 +0100
    Re: filter a list of strings jmp <jeanmichel@sequans.com> - 2015-12-03 11:03 +0100
    Re: filter a list of strings Peter Otten <__peter__@web.de> - 2015-12-03 11:13 +0100
    Re: filter a list of strings Denis McMahon <denismfmcmahon@gmail.com> - 2015-12-03 14:16 +0000
      Re: filter a list of strings Jussi Piitulainen <harvesting@is.invalid> - 2015-12-03 17:02 +0200
  Re: filter a list of strings Grobu <snailcoder@retrosite.invalid> - 2015-12-03 13:17 +0100

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