You need to use a numeric sort (the default is alphabetic). Provided the numbers are at the start of the line you can just do this:

my @data = <DATA>;
my @alpha_sort   = sort { $a cmp $b } @data;
my @numeric_sort = sort { $a <=> $b } @data;

print "Alpha sort\n@alpha_sort\n";
print "Numeric sort\n@numeric_sort\n";

__DATA__
123.45Hello
32.2World
1.5Just
288.2Another
288.3Perl
288.4Hacker
[download]

If you have more complex requirements then a Schwartzian transform will be in order.

cheers

tachyon

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