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Re: lstrip problem - beginner question

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On 4 Jun 2013 16:34, "mstagliamonte" <madmaxthc@yahoo.it> wrote:
>
> On Tuesday, June 4, 2013 11:21:53 AM UTC-4, mstagliamonte wrote:
> > Hi everyone,
> >
> >
> >
> > I am a beginner in python and trying to find my way through... :)
> >
> >
> >
> > I am writing a script to get numbers from the headers of a text file.
> >
> >
> >
> > If the header is something like:
> >
> > h01 = ('>scaffold_1')
> >
> > I just use:
> >
> > h01.lstrip('>scaffold_')
> >
> > and this returns me '1'
> >
> >
> >
> > But, if the header is:
> >
> > h02: ('>contig-100_0')
> >
> > if I use:
> >
> > h02.lstrip('>contig-100_')
> >
> > this returns me with: ''
> >
> > ...basically nothing. What surprises me is that if I do in this other
way:
> >
> > h02b = h02.lstrip('>contig-100')
> >
> > I get h02b = ('_1')
> >
> > and subsequently:
> >
> > h02b.lstrip('_')
> >
> > returns me with: '1' which is what I wanted!
> >
> >
> >
> > Why is this happening? What am I missing?
> >
> >
> >
> > Thanks for your help and attention
> >
> > Max
>
> edit: h02: ('>contig-100_1')

You don't have to use ('..') to declare a string. Just 'your string' will
do.

You can use str.split to split your string by a character.

(Not tested)

string_on_left, numbers = '>contig-100_01'.split('-')
left_number, right_number = numbers.split('_')
left_number, right_number = int(left_number), int(right_number)

Of course, you will want to replace the variable names.

If you have more advanced parsing needs, you will want to look at regular
expressions or blobs.

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Thread

lstrip problem - beginner question mstagliamonte <madmaxthc@yahoo.it> - 2013-06-04 08:21 -0700
  Re: lstrip problem - beginner question mstagliamonte <madmaxthc@yahoo.it> - 2013-06-04 08:24 -0700
  Re: lstrip problem - beginner question mstagliamonte <madmaxthc@yahoo.it> - 2013-06-04 08:25 -0700
    Re: lstrip problem - beginner question Fábio Santos <fabiosantosart@gmail.com> - 2013-06-04 16:41 +0100
      Re: lstrip problem - beginner question mstagliamonte <madmaxthc@yahoo.it> - 2013-06-04 08:49 -0700
        Re: lstrip problem - beginner question Mark Lawrence <breamoreboy@yahoo.co.uk> - 2013-06-04 17:01 +0100
        Re: lstrip problem - beginner question Dave Angel <davea@davea.name> - 2013-06-04 17:48 -0400
  Re: lstrip problem - beginner question mstagliamonte <madmaxthc@yahoo.it> - 2013-06-04 08:28 -0700
  Re: lstrip problem - beginner question mstagliamonte <madmaxthc@yahoo.it> - 2013-06-04 08:29 -0700
  Re: lstrip problem - beginner question MRAB <python@mrabarnett.plus.com> - 2013-06-04 16:48 +0100
    Re: lstrip problem - beginner question mstagliamonte <madmaxthc@yahoo.it> - 2013-06-04 08:53 -0700
  Re: lstrip problem - beginner question Peter Otten <__peter__@web.de> - 2013-06-04 17:52 +0200
  Re: lstrip problem - beginner question John Gordon <gordon@panix.com> - 2013-06-04 15:55 +0000
    Re: lstrip problem - beginner question mstagliamonte <madmaxthc@yahoo.it> - 2013-06-04 09:06 -0700
  Re: lstrip problem - beginner question Larry Hudson <orgnut@yahoo.com> - 2013-06-04 21:53 -0700

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