I get this error when i m running this script:

Code

#!/usr/bin/perl

use strict;

use warnings;

use Bio::Tools::Run::Alignment::Muscle;

# Build a muscle alignment factory

my @params = ( -outfile_name => 'outfile.fa' );

my $factory = Bio::Tools::Run::Alignment::Muscle->new(@params);

# Pass the factory a list of sequences to be aligned .

my $inputfilename = 'sequence.fasta';

# $aln is a SimpleAlign object .

my $aln = $factory->align( $inputfilename );

exit;

Error message:

'-in' not recognized as an internal or external command,

executable program or script file.

--------------------- WARNING ---------------------MSG: Muscle call crashed: 256 [command -in sequence.fa -out outfile.fa]---------------------------------------------------

Any clue pleaze???