#!/usr/bin/perl -w

use strict;

my @seq = ( "A", "T", "C", "G" );
my $length = 10000;

undef my %hash;
$hash{"A"} = int( $length * 0.3 );
$hash{"C"} = int( $length * 0.3 );
$hash{"G"} = int( $length * 0.2 );
$hash{"T"} = int( $length * 0.2 );

my $i = 0;
while ( $i 《 $length ) {
    my $word = $seq[ rand(@seq) ];
    if ( $hash{$word} ) {
        print "$word";
        $i++;
    }
    $hash{$word}--;
}
print "n";

#!/usr/bin/perl

use strict;
use warnings;

use BioX::SeqUtils::RandomSequence;

my $randomizer = BioX::SeqUtils::RandomSequence-》new(
    {
        l =》 10000,
        s =》 1,
        y =》 "dna",
        a =》 3,
        c =》 3,
        g =》 2,
        t =》 2
    }
);
print $randomizer-》rand_seq(), "n";

withoutModule Length=10000 GC=49.42% A=2558,C=2503,G=2439,T=2500,Others=0
withModule Length=10000 GC=50.00% A=3000,C=3000,G=2000,T=2000,Others=0