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Re: Read csv file and create a new file

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On 02/28/2013 02:14 PM, io wrote:
> Hi,
>
> i have to files.
>
> First file is a csv file
> Second file is a plain text file where each row has a value (text)
>
> I want to be able to create a third file using data from the first file
> excluding the values listed in the second file.
>
> Example:
>
> First file:
> -----------
>
> mtgoxeur	12	24	36
> mtgoxusd	10	12	14
> mtgoxpln	2	4	6
>
>
> Second file:
> ------------
>
> mtgoxusd
>
>
>
> Third File (the resulting one) :
> --------------------------------
>
> mtgoxeur	12	24	36
> mtgoxpln	2	4	6
>
>
>
> Thanks to anyone that can help
>
>


Start by making a set out of the second file.  Don't forget to remove 
whitespace with strip()

Then loop through the first file.  For each line, split() it by 
whitespace, and conditionally write the line to the third file.  The 
test would be something like:
      if  fields[0] in myset:
            outfile.write(line)


-- 
DaveA

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Thread

Read csv file and create a new file io <maroso@libero.it> - 2013-02-28 19:14 +0000
  Re: Read csv file and create a new file Neil Cerutti <neilc@norwich.edu> - 2013-02-28 19:32 +0000
  Re: Read csv file and create a new file Joel Goldstick <joel.goldstick@gmail.com> - 2013-02-28 14:34 -0500
  Re: Read csv file and create a new file Dave Angel <davea@davea.name> - 2013-02-28 14:35 -0500
  Re: Read csv file and create a new file io <maroso@libero.it> - 2013-02-28 19:51 +0000
    Re: Read csv file and create a new file Neil Cerutti <neilc@norwich.edu> - 2013-02-28 20:11 +0000
      Re: Read csv file and create a new file io <maroso@libero.it> - 2013-02-28 20:23 +0000
        Re: Read csv file and create a new file io <maroso@libero.it> - 2013-02-28 20:46 +0000
          Re: Read csv file and create a new file io <maroso@libero.it> - 2013-02-28 20:51 +0000
          Re: Read csv file and create a new file Dave Angel <davea@davea.name> - 2013-02-28 16:23 -0500
            Re: Read csv file and create a new file io <maroso@libero.it> - 2013-02-28 22:05 +0000
              Re: Read csv file and create a new file Dave Angel <davea@davea.name> - 2013-02-28 19:13 -0500
  Re: Read csv file and create a new file Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2013-02-28 21:04 -0500
    Re: Read csv file and create a new file io <maroso@libero.it> - 2013-03-04 19:04 +0000
      Re: Read csv file and create a new file Steven D'Aprano <steve+comp.lang.python@pearwood.info> - 2013-03-04 23:58 +0000

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