File Coverage

blib/lib/Statistics/Lite.pm

Criterion	Covered	Total	%
statement	110	112	98.2
branch	48	70	68.5
condition			n/a
subroutine	17	18	94.4
pod	15	16	93.7
total	190	216	87.9

package Statistics::Lite;
use strict;
use vars qw($VERSION @ISA @EXPORT @EXPORT_OK %EXPORT_TAGS);
require Exporter;

$VERSION = '3.6';
@ISA = qw(Exporter);
@EXPORT = ();
@EXPORT_OK = qw(min max range sum count mean median mode variance stddev variancep stddevp statshash statsinfo frequencies);
%EXPORT_TAGS=
(
	all   => [ @EXPORT_OK ],
	funcs => [qw],
	stats => [qw],
);

sub definedvals
{
	return grep{defined}@_;
}

sub count
{
	return scalar definedvals @_;
}

sub min
{
	my @data = definedvals @_;
	return unless @data;
	return $data[0] unless @data > 1;
	my $min= shift @data;
	foreach(@data) { $min= $_ if $_ < $min; }
	return $min;
}

sub max
{
	my @data = definedvals @_;
	return unless @data;
	return $data[0] unless @data > 1;
	my $max= shift @data;
	foreach(@data) { $max= $_ if $_ > $max; }
	return $max;
}

sub range
{
	my @data = definedvals @_;
	return unless @data;
	return 0 unless @data > 1;
	return abs($data[1]-$data[0]) unless @data > 2;
	my $min= shift @data; my $max= $min;
	foreach(@data) { $min= $_ if $_ < $min; $max= $_ if $_ > $max; }
	return $max - $min;
}

sub sum
{
	my @data = definedvals @_;
	return unless @data;
	return $data[0] unless @data > 1;
	my $sum;
	foreach(@data) { $sum+= $_; }
	return $sum;
}

sub mean
{
	my @data = definedvals @_;
	return unless @data;
	return $data[0] unless @data > 1;
	return sum(@data)/scalar(@data);
}

sub median
{
	my @data = definedvals @_;
	return unless @data;
	return $data[0] unless @data > 1;
	@data= sort{$a<=>$b}@data;
	return $data[$#data/2] if @data&1;
	my $mid= @data/2;
	return ($data[$mid-1]+$data[$mid])/2;
}

sub mode
{
	my @data = definedvals @_;
	return unless @data;
	return $data[0] unless @data > 1;
	my %count;
	foreach(@data) { $count{$_}++; }
	my $maxhits= max(values %count);
	foreach(keys %count) { delete $count{$_} unless $count{$_} == $maxhits; }
	return mean(keys %count);
}

sub variance
{
	my @data = definedvals @_;
	return unless @data;
	return 0 unless @data > 1;
	my $mean= mean @data;
	return (sum map { ($_ - $mean)**2 } @data) / $#data;
}

sub variancep
{
	my @data = definedvals @_;
	return unless @data;
	return 0 unless @data > 1;
	my $mean= mean @data;
	return (sum map { ($_ - $mean)**2 } @data) / ( $#data +1 );
}

sub stddev
{
	my @data = definedvals @_;
	return unless @data;
	return 0 unless @data > 1;
	return sqrt variance @data;
}

sub stddevp
{
	my @data = definedvals @_;
	return unless @data;
	return 0 unless @data > 1;
	return sqrt variancep @data;
}

sub statshash
{
	my @data = definedvals @_;
	return unless @data;
	return
	(
		count     => 1,
		min       => $data[0],
		max       => $data[0],
		range     => 0,
		sum       => $data[0],
		mean      => $data[0],
		median    => $data[0],
		mode      => $data[0],
		variance  => 0,
		stddev    => 0,
		variancep => 0,
		stddevp   => 0
	) unless @data > 1;
	my $count= scalar(@data);
	@data= sort{$a<=>$b}@data;
	my $median;
	if(@data&1) { $median= $data[$#data/2]; }
	else { my $mid= @data/2; $median= ($data[$mid-1]+$data[$mid])/2; }
	my $sum= 0;
	my %count;
	foreach(@data) { $sum+= $_; $count{$_}++; }
	my $mean= $sum/$count;
	my $maxhits= max(values %count);
	foreach(keys %count)
	{ delete $count{$_} unless $count{$_} == $maxhits; }
	return
	(
		count     => $count,
		min       => $data[0],
		max       => $data[-1],
		range     => ($data[-1] - $data[0]),
		sum       => $sum,
		mean      => $mean,
		median    => $median,
		mode      => mean(keys %count),
		variance  => variance(@data),
		stddev    => stddev(@data),
		variancep => variancep(@data),
		stddevp   => stddevp(@data)
	);
}

sub statsinfo
{
	my %stats= statshash(@_);
	return <<".";
min       = $stats{min}
max       = $stats{max}
range     = $stats{range}
sum       = $stats{sum}
count     = $stats{count}
mean      = $stats{mean}
median    = $stats{median}
mode      = $stats{mode}
variance  = $stats{variance}
stddev    = $stats{stddev}
variancep = $stats{variancep}
stddevp   = $stats{stddevp}
.
}

sub frequencies
{
	my @data = definedvals @_;
	return unless @data;
	return ( $data[0], 1 ) unless @data > 1;
	my %count;
	foreach(@data) { $count{$_}++; }
	return %count;
}

1;
__END__