File Coverage

blib/lib/Math/Business/SMA.pm

Criterion	Covered	Total	%
statement	37	39	94.8
branch	8	10	80.0
condition			n/a
subroutine	7	9	77.7
pod	0	6	0.0
total	52	64	81.2

package Math::Business::SMA;

use strict;
use warnings;
use Carp;

1;

sub tag { (shift)->{tag} }

sub recommended { croak "no recommendation" }

sub new {
    my $class = shift;
    my $this  = bless {
        val => [],
        cur => undef,
        rec => 1,
    }, $class;

    my $days = shift;
    if( defined $days ) {
        $this->set_days( $days );
    }

    return $this;
}

sub set_days {
    my $this = shift;
    my $arg  = int(shift);

    croak "days must be a positive non-zero integer" if $arg <= 0;

    $this->{val} = [];
    delete $this->{SMA};
    $this->{days} = $arg;
    $this->{tag} = "SMA($this->{days})";
}

sub insert {
    my $this = shift;
    my $val  = $this->{val};
    my $N    = $this->{days};

    croak "You must set the number of days before you try to insert" if not defined $N;

    while( defined(my $PM = shift) ) {
        push @$val, $PM;

        if( @$val >= $N ) {
            if( defined( my $s = $this->{SMA} ) ) {
                my $old = shift @$val;
                $this->{SMA} = $s - $old/$N + $PM/$N;

            } else {
                my $sum = 0;
                   $sum += $_ for @$val;

                $this->{SMA} = $sum/$N;
            }
        }
    }
}

sub query {
    my $this = shift;

    return $this->{SMA};
}

__END__