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Re: Fastest way to remove the first x characters from a very long string

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On Saturday, May 16, 2015 at 9:46:17 AM UTC-4, Chris Angelico wrote:
> On Sat, May 16, 2015 at 11:28 PM,  <bruceg113355@gmail.com> wrote:
> > I have a string that contains 10 million characters.
> >
> > The string is formatted as:
> >
> > "0000001 : some hexadecimal text ... \n
> > 0000002 : some hexadecimal text ... \n
> > 0000003 : some hexadecimal text ... \n
> > ...
> > 0100000 : some hexadecimal text ... \n
> > 0100001 : some hexadecimal text ... \n"
> >
> > and I need the string to look like:
> >
> > "some hexadecimal text ... \n
> > some hexadecimal text ... \n
> > some hexadecimal text ... \n
> > ...
> > some hexadecimal text ... \n
> > some hexadecimal text ... \n"
> >
> > I can split the string at the ":" then iterate through the list removing the first 8 characters then convert back to a string. This method works, but it takes too long to execute.
> >
> > Any tricks to remove the first n characters of each line in a string faster?
> 
> Given that your definition is "each line", what I'd advise is first
> splitting the string into lines, then changing each line, and then
> rejoining them into a single string.
> 
> lines = original_text.split("\n")
> new_text = "\n".join(line[8:] for line in lines)
> 
> Would that work?
> 
> ChrisA


Hi Chris,

I meant to say I can split the string at the \n.

Your approach using .join is what I was looking for.
Thank you,

Bruce

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Fastest way to remove the first x characters from a very long string bruceg113355@gmail.com - 2015-05-16 06:28 -0700
  Re: Fastest way to remove the first x characters from a very long string Joel Goldstick <joel.goldstick@gmail.com> - 2015-05-16 09:43 -0400
  Re: Fastest way to remove the first x characters from a very long string Chris Angelico <rosuav@gmail.com> - 2015-05-16 23:45 +1000
    Re: Fastest way to remove the first x characters from a very long string bruceg113355@gmail.com - 2015-05-16 07:02 -0700
      Re: Fastest way to remove the first x characters from a very long string bruceg113355@gmail.com - 2015-05-16 09:22 -0700
        Re: Fastest way to remove the first x characters from a very long string Ian Kelly <ian.g.kelly@gmail.com> - 2015-05-16 10:57 -0600
        Re: Fastest way to remove the first x characters from a very long string Chris Angelico <rosuav@gmail.com> - 2015-05-17 02:59 +1000
          Re: Fastest way to remove the first x characters from a very long string bruceg113355@gmail.com - 2015-05-16 10:35 -0700
            Re: Fastest way to remove the first x characters from a very long string Cameron Simpson <cs@zip.com.au> - 2015-05-17 08:41 +1000
  Re: Fastest way to remove the first x characters from a very long string Grant Edwards <invalid@invalid.invalid> - 2015-05-16 14:59 +0000
    Re: Fastest way to remove the first x characters from a very long string Rustom Mody <rustompmody@gmail.com> - 2015-05-16 08:13 -0700
      Re: Fastest way to remove the first x characters from a very long string bruceg113355@gmail.com - 2015-05-16 09:24 -0700
        Re: Fastest way to remove the first x characters from a very long string Irmen de Jong <irmen.NOSPAM@xs4all.nl> - 2015-05-16 18:55 +0200
  Re: Fastest way to remove the first x characters from a very long string Denis McMahon <denismfmcmahon@gmail.com> - 2015-05-16 23:24 +0000

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