.0000000001;2;1;.5;.2
.5;2;1;.5;.5
0.3;1.5;.5;.5;.2
1;1;.7;1;1
.4;1;.4;1;.5

##</code><code>##

#!/usr/bin/perl

use strict;
use diagnostics;
use warnings;

my $fh;
my @lines = ();
my @sortedlines = ();

open($fh, "<", "filename") or die "I cannot open the file: $!\n";
chomp(@lines = <$fh>);

@sortedlines = sort { $b =~ /(^\d*\.*\d+);/ <=> $a =~ /(^\d*\.*\d+);/ } @lines;
print "SORTED LINES = @sortedlines\n";