use strict;
use warnings;
use Math::FFT;
use PDL;
use PDL::Graphics::Simple;

my $filePath = $ARGV[0] // "testData.txt";

my @data = do { open my $fh, $filePath or die "Can't open $filePath: $!"; local $/; split /\s+/, <$fh> };

my $fft = Math::FFT->new(\@data);
my $spectrum = $fft->spctrm;
shift @$spectrum; # Remove DC signal component

line pdl($spectrum);
print "ret> "; <STDIN>;