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

References <6a383ce2-5975-4225-b4f2-f744c9d7a516@googlegroups.com>
Date 2015-05-16 23:45 +1000
Subject Re: Fastest way to remove the first x characters from a very long string
From Chris Angelico <rosuav@gmail.com>
Newsgroups comp.lang.python
Message-ID <mailman.72.1431783967.17265.python-list@python.org> (permalink)

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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

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Thread

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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