Would have been better for you if you showed us what you came up with ... but anyway, this is one way to do it

use Bio::SeqIO

my $in  = Bio::SeqIO->new(-file => "test.fa" , '-format' => 'Fasta');
my $out = Bio::SeqIO->new(-file => ">out.fa" , '-format' => 'Fasta');
 
while ( my $seq = $in->next_seq() ) { 
  $out->write_seq($seq) if($seq->length > 500);
}

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In reply to Re: Parse DNA fasta file by arun_kom
in thread Parse DNA fasta file by Anonymous Monk

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