Hi, I'm trying to get the perl module PDL::GSLSF::GAMMA working but am having some difficulty. As I understand it, the function "gsl_sf_gamma" should return the gamma function "Gamma(x)". For example, in R:

`> gamma(0.4)
[1] 2.21816
`

However, I can't seem to replicate this using PDL:

`#!/usr/bin/perl
use PDL;
use PDL::GSLSF::GAMMA;
my $out = gsl_sf_gamma(0.4);
print "$out\n";
`

Output is "1.63493983016443e-14".
I'm clearly doing something wrong, please excuse my ignorance. Any help greatly appreciated.