use Test::More;
use PDL::LiteF;
use strict;
use warnings;
BEGIN {
eval {
require PDL::Fit::Linfit;
PDL::Fit::Linfit->import();
1;
} or plan skip_all => "PDL::Fit::Linfit: $@";
}
kill 'INT',$$ if $ENV{UNDER_DEBUGGER}; # Useful for debugging.
plan tests => 2;
{
# Simple Test Case:
# Generate data from a set of functions
my $xvalues = sequence(100);
my $data = 3*$xvalues + 2*cos($xvalues) + 3*sin($xvalues*2);
# Fit functions are the linear, cos, and sin2x functions used in
# the data generation step above:
my $fitFuncs = cat $xvalues, cos($xvalues), sin($xvalues*2);
# Perform the fit, Coefs should equal 3,2,3
my ($yfit, $coeffs) = PDL::linfit1d($data, $fitFuncs);
my @coefs = $coeffs->list;
ok all approx( $coeffs, pdl([3,2,3]) );
}
{
# More Complex Example
my $noPoints = 501;
my @expectedCoefs = qw( 0.988375918186647 -0.000278823311771375 0.161669997297754 0.0626069008452451);
my $noCoefs = 4;
my $i;
my ($deltaT,$Amp,$lin,$HOper,$AmpHO,$Amphalf,$Ampfull);
my @PulsedB;
my @Pulse;
my $psum = 0;
my $pi = 3.1415926;
my $Pwidth = 2000;
my $pave;
$deltaT = 4; # 4 nS increments
$Amp = 2.8; # 2.8V amplitude of pulse
$lin = .2;
$HOper = 200; # HO period
$AmpHO=.1;
$Amphalf = .5;
$Ampfull = .2;
# generate waveform:
for(my $i = 0; $i < $noPoints; $i++){
$PulsedB[$i]=
-$lin*1e-3*$i*$deltaT +
$Amphalf*sin($pi/$Pwidth*$i*$deltaT) +
$Ampfull*sin(2*$pi/$Pwidth*$i*$deltaT) +
$AmpHO*sin(2*$pi/$HOper*$i*$deltaT);
$Pulse[$i] = $Amp*exp($PulsedB[$i]/20*2.3025851);
$psum += $Pulse[$i]; # used to get DC value
# printf(" %4d %g %g\n",$i,$PulsedB[$i],$Pulse[$i]);
}
$pave = $psum/$noPoints;
# printf("DC Value = %g\n",$pave);
# Make PDL from waveform:
my $data = new PDL( \@Pulse);
my @functions;
# setup matrix contains functions to fit
for ($i=0; $i<$noPoints; $i++) {
$functions[0][$i] = $pave;
$functions[1][$i] = $i;
$functions[2][$i] = sin($pi*$i/($noPoints-1));
$functions[3][$i] = sin(2*$pi*$i/($noPoints-1));
}
my $fitFuncs = new PDL( \@functions);
my ($yfit, $coeffs) = linfit1d( $data, $fitFuncs);
my @coefs = $coeffs->list;
ok all approx( $coeffs, pdl( \@expectedCoefs ) );
}