mutaciones

use warnings;

print "please type the filename of the sequence data ";
$DNAfilename= <STDIN>;
chomp $DNAfilename;
open (DNAFILE,$DNAfilename);
@DNA= <DNAFILE>;
close DNAFILE;

$DNA=join ('',@DNA);
$DNA=~ s/\s//g;

my $DNAname = 'Wolbachiagenoma.fasta';
my $i;
my $mutant;
my $filename = 'report.txt';
open(my $fh, '>', $filename) or die "Could not open file '$filename' $!";

srand(time|$$);
$mutant = mutate($DNA);

print $fh "\nMutate DNA\n\n";

print $fh "\nHere is the original DNA:\n\n";
print $fh "$DNA\n";

print $fh "\nHere is the mutant DNA:\n\n";
print $fh "$mutant\n";

print $fh "\nHere are 10 more successive mutations:\n\n";

for ($i=0 ; $i < 10 ; ++$i) {
    $mutant = mutate($mutant);
    print $fh "$mutant\n";
}

close $fh;
print "done\n";

exit;

sub mutate {

    my($dna) = @_;

    my(@nucleotides) = ('A', 'C', 'G', 'T');

my($position) = randomposition($dna);
my($newbase) = randomnucleotide(@nucleotides);

substr($dna,$position,1,$newbase);

    return $dna;
}


sub randomelement {

    my(@array) = @_;

    return $array[rand @array];
}

sub randomnucleotide {

    my(@nucleotides) = ('A', 'C', 'G', 'T');

    # scalar returns the size of an array.
    # The elements of the array are numbered 0 to size-1
    return randomelement(@nucleotides);
}


sub randomposition {

    my($string) = @_;
return int rand length $string;
}