#!/usr/bin/env perl

# INPUT
my $num = "12.3456";

# VIA SPRINTF
my $out1 = sprintf('%.2f',$num);
print "$out1\n";

# VIA REGEX (one of many..)
$num =~ m/(.*)\.(..).*/;
my $out2 = "$1.$2";
print "$out2\n";

# VIA FORMAT TEMPLATE
format MyNumber =
@#.##
$num
.
select(STDOUT);
$~ = MyNumber;
write;