#! perl -slw use strict; use Benchmark::Timer; use List::Util qw[ sum reduce ]; use Math::Pari qw[ factorial ]; $a=$b; sub product{ reduce{ $a *= $b } 1, @_ } sub FishersExactTest { my @data = @_; return unless @data == 4; my @C = ( sum( @data[ 0, 2 ] ), sum( @data[ 1, 3 ] ) ); my @R = ( sum( @data[ 0, 1 ] ), sum( @data[ 2, 3 ] ) ); my $N = sum @C; my $dividend = product map{ factorial $_ } grep $_, @R, @C; my $divisor = product map{ factorial $_ } grep $_, $N, @data; return $dividend / $divisor; } my $T = new Benchmark::Timer; $T->start( '' ); print FishersExactTest 989, 9400, 43300, 2400;; $T->stop( '' ); $T->report; __END__ P:\test>MP-FET.pl 8.070604647867604097576877668E-7030 1 trial of _default ( 25.852ms total), 25.852ms/trial