Not sure of your data but this might help: 
my @seqList;
my @sequences;
my $dnaString;
my $count = 0;

my @DNA = <DATA>;
foreach my $line (@DNA) {
    if ($line=~/^>(\S+)/){
        push (@seqList, $1);
        push (@sequences, $dnaString) if $count++;
        $dnaString = '';
    }
    else {
        chomp $line;
        $dnaString .= $line;
    }
}
push (@sequences, $dnaString); # need to push last one

__DATA__
>123 blah
abcdef
ghijkl
>456 de dah
mnopqr
>789 nothing wanted here
stuvwxyz


# OUTPUT
@seqList = (
          '123',
          '456',
          '789'
        );
@sequences = (
          'abcdefghijkl',
          'mnopqr',
          'stuvwxyz'
        );

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In reply to Re: Creating 2 arrays from a larger array by tangent
in thread Creating 2 arrays from a larger array by imtakinbioinformatic

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