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Re: looking for a neat solution to a nested loop problem

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On 2012-08-06, Tom P <werotizy@freent.dd> wrote:

>>>> no, I meant something else ..
>>>>
>>>>     j runs through range(M, 100) and then range(0,M), and i runs through
>>>> range(N,100) and then range(0,N)
>>>
>>> In 2.x:
>>>
>>>      for i in range(M,100)+range(0,M):
>>>          for j in range(N,100)+range(0,N):
>>>              do_something(i,j)
>>>
>>> Dunno if that still works in 3.x.  I doubt it, since I think in 3.x
>>> range returns an iterator, not?
>>
>> Indeed it doesn't work in 3.x, but this does:
>>
>>      from itertools import chain
>>
>>      for i in chain(range(M,100),range(0,M)):
>>          for j in chain(range(N,100),range(0,N)):
>>              do_something(i,j)
>
>   ah, that looks good - I guess it works in 2.x as well?

I don't know.  Let me test that for you...

   $ python
   Python 2.6.8 (unknown, May 18 2012, 11:56:26) 
   [GCC 4.5.3] on linux2
   Type "help", "copyright", "credits" or "license" for more information.
   >>> from itertools import chain
   >>> for i in chain(range(0,5),range(5,10)):
   ...   print i
   ... 
   0
   1
   2
   3
   4
   5
   6
   7
   8
   9
   >>> 

Yes, it works in 2.x as well.

-- 
Grant Edwards               grant.b.edwards        Yow! ... bleakness
                                  at               ... desolation ... plastic
                              gmail.com            forks ...

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looking for a neat solution to a nested loop problem Tom P <werotizy@freent.dd> - 2012-08-06 17:52 +0200
  Re: looking for a neat solution to a nested loop problem John Gordon <gordon@panix.com> - 2012-08-06 16:03 +0000
    Re: looking for a neat solution to a nested loop problem Tom P <werotizy@freent.dd> - 2012-08-06 19:16 +0200
      Re: looking for a neat solution to a nested loop problem Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2012-08-07 01:27 +0000
  Re: looking for a neat solution to a nested loop problem Ian Foote <ian@feete.org> - 2012-08-06 17:07 +0100
  Re: looking for a neat solution to a nested loop problem Ethan Furman <ethan@stoneleaf.us> - 2012-08-06 09:15 -0700
  Re: looking for a neat solution to a nested loop problem Nobody <nobody@nowhere.com> - 2012-08-06 17:18 +0100
    Re: looking for a neat solution to a nested loop problem Tom P <werotizy@freent.dd> - 2012-08-06 19:14 +0200
      Re: looking for a neat solution to a nested loop problem Emile van Sebille <emile@fenx.com> - 2012-08-06 11:11 -0700
        Re: looking for a neat solution to a nested loop problem Larry Hudson <orgnut@yahoo.com> - 2012-08-06 21:02 -0700
          Re: looking for a neat solution to a nested loop problem Nobody <nobody@nowhere.com> - 2012-08-07 16:32 +0100
            Re: looking for a neat solution to a nested loop problem 88888 Dihedral <dihedral88888@googlemail.com> - 2012-08-07 18:42 -0700
            Re: looking for a neat solution to a nested loop problem 88888 Dihedral <dihedral88888@googlemail.com> - 2012-08-09 11:46 -0700
            Re: looking for a neat solution to a nested loop problem 88888 Dihedral <dihedral88888@googlemail.com> - 2012-08-09 11:39 -0700
            Re: looking for a neat solution to a nested loop problem 88888 Dihedral <dihedral88888@googlemail.com> - 2012-08-14 14:08 -0700
      Re: looking for a neat solution to a nested loop problem Grant Edwards <invalid@invalid.invalid> - 2012-08-06 18:25 +0000
        Re: looking for a neat solution to a nested loop problem Grant Edwards <invalid@invalid.invalid> - 2012-08-06 18:29 +0000
          Re: looking for a neat solution to a nested loop problem Tom P <werotizy@freent.dd> - 2012-08-06 21:03 +0200
            Re: looking for a neat solution to a nested loop problem Grant Edwards <invalid@invalid.invalid> - 2012-08-06 19:22 +0000
              Re: looking for a neat solution to a nested loop problem Emile van Sebille <emile@fenx.com> - 2012-08-06 12:52 -0700
  Re: looking for a neat solution to a nested loop problem André Malo <ndparker@gmail.com> - 2012-08-06 20:19 +0200
  Re: looking for a neat solution to a nested loop problem Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2012-08-06 15:31 -0400
  Re: looking for a neat solution to a nested loop problem Arnaud Delobelle <arnodel@gmail.com> - 2012-08-06 21:14 +0100

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