Re: [FWP] More Simplification

[Rick Delaney <rick.delaney@home.com>]

Vicki Brown wrote:
> 
> Problem: Convert all characters not in the set [AaTtCcGg] to [Nn],
> preserving case

What do you mean by characters or by preserving case?  Should "_" be
converted to "N" or "n"?

> Solution A (presented to me)
> 
>        $seq =~ s/([^ACTGNactgn])/chr(ord(N) - (ord(uc($1)) - ord($1)))/eg;

aka

    $seq =~ s/([^actgn])/'N' ^ uc($1) ^ $1/eig;

> Solution B (mine)
> 
>          $seq =~ tr/[A-Zatcgn]/n/c;
>          $seq =~ tr/[a-zATCGN]/N/c;

This ain't quite the same as A.  Solution A converts all non-letters
(outside the set) to 'N', while B converts all non-letters (outside the
set) to 'n' (except for '[' and ']' which for some reason are left alone
:-)

-- 
Rick Delaney
rick.delaney@home.com