Tasks like this can be solved by using BioPerl. 
use strict;
use warnings;
use Bio::SeqIO;

# Reading the fasta file
my $seqio_obj = Bio::SeqIO->new(-file => "Genes.fasta", 
                             -format => "fasta" );

# Looping through sequences and printing them unless length <= 10     
+                        
while ( my $seq_obj = $seqio_obj->next_seq ) {
    print $seq_obj->seq,"\n" unless $seq_obj->length <= 10;
}
# The output should be : "GGAGGTCTTTAGCTTTAGGGAAACCC".

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In reply to Re: Size of sequences in fastafile by zubenel0
in thread Size of sequences in fastafile by Sofie

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