I might do it this way:
(>@:{. ; ;@}.)@(LF&cut) x
┌───────┬─────────────┐
│case_id│GCTAGTCGACGTC│
└───────┴─────────────┘
On Tue, Nov 25, 2014 at 5:47 AM, Jan-Pieter Jacobs <
janpieter.jac...@gmail.com> wrote:
> I think I would solve it like this (with intermediate steps):
>
> x=: 'case_id', LF, 'GCTAGTCG', LF, 'ACGTC', LF
>
> NB. Find the locations of LF's in the string
> (LF = ]) x
>
> NB. assign 0 to everything before the LF, assign 1 to everything after it
> ([: +./\ LF = ]) x
>
> NB. The wonderful "key" adverb lets you apply verbs based on it's key
> (another array), eg. box
> (</.~ [: +./\ LF =]) x
>
> NB. Get rid of the LF's by replacing < by a version removing LF:
> ((<@#~ LF~:])/.~ [: +./\ LF = ]) x
>
> This is what I came up with, but smarter people will probably suggest more
> elegant ways.
>
> I hope this is useful.
> Jan-Pieter
>
> 2014-11-25 11:00 GMT+01:00 Ryan <rec...@bwh.harvard.edu>:
>
> > I have a character array with LF's, and want to split it on the
> > first LF, and remove the remaining LF's. I'm wondering if there's a
> > simpler
> > way than what I'm doing now:
> >
> > x=: 'case_id', LF, 'GCTAGTCG', LF, 'ACGTC', LF
> >
> > filterLF=: #~ ~:&LF
> > headLF=: {.~ i.&LF
> > tailLF=: }.~ i.&LF
> > (headLF ; filterLF@tailLF) x
> > ┌────────┬─────────────┐
> > │>case_id│GCTAGTCGACGTC│
> > └────────┴─────────────┘
> >
> > (I'm reading text files in fasta format: http://rosalind.info/glossary/
> > fasta-format/)
> >
> > Thanks for any suggestions,
> > Ryan
> >
> >
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