I'm a newbie to Perl, having started about a month ago by working out of a book called "Perl Programming for Biologists". I'm working with subroutines, and am trying to work on a program to separate nucleotide sequences based on GC content using the sort function.

So far, this is what I have: 
@sequences = (ATATGACTTG,
GGGGATCCAC,
ATACATATAC,
AGGCTACGCT,
GAGGCCGCGC);

@list = sort GC @sequences;


sub GC{
$count = 0; #keep count of g and c per sequence
$index = 0; #cycle through each item in list
for ($count = 0; { #Not sure, I've tried many things.
if(g == $sequences{$index}) {$total = $count + 1}
if(c == $sequences{$index}) {$total = $count + 1}
$index++;
return($a cmp $b);
}
}

print join("\n", @list), "\n";

[download]
If I can get guidance, criticism, or help on this and what I'm doing wrong, that will be very much appreciated. Thanks all, perl is my first computer language so I plan to stick with it.

In reply to Help Manipulating Sort with Subroutines by La Familia

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