File Coverage

blib/lib/Math/Preference/SVD.pm

Criterion	Covered	Total	%
statement	9	51	17.6
branch	0	12	0.0
condition			n/a
subroutine	3	6	50.0
pod	0	3	0.0
total	12	72	16.6

#!/usr/bin/perl

package Math::Preference::SVD;

use strict;
use warnings;

no AutoLoader;

our $VERSION = '0.01';

require XSLoader;
XSLoader::load('Math::Preference::SVD', $VERSION);

sub new {
    my $class = shift;
    bless { @_ }, $class;
}

# sub set_rating {
#     # doing just one would be tricky... have to figure out if the movie has already been seen and add it if not
#     # customers add themselves as necessary I think
#     my $self = shift;
# }

sub set_ratings {
    my $self = shift;
    my $ratings = shift;   # array of arrays, each of those having customer_id, movie_id (or, in general, id of the thing rated), rating
    my @ratings = @{ $ratings };
    my $max_movie_id = 0;
    my $max_customer_id = 0;
    my $max_rating_id = 0;

    @ratings = sort { $a->[1] <=> $b->[1] } @ratings; # sort by movie
    $max_movie_id = $ratings[-1]->[1];

    for my $rating ( @ratings ) {
        die unless ref $rating eq 'ARRAY';
        (my $custId, my $movieId, my $rating) = @{ $rating };
        defined $custId or die;
        defined $movieId or die;
        defined $rating or die;
        $max_customer_id = $custId if $custId > $max_customer_id;
        $max_rating_id++;
    }
warn "totals calced: customers: @{[ $max_customer_id + 1 ]}  ratings: $max_rating_id  movies: @{[ $max_movie_id + 1 ]}";
    Engine($max_customer_id+1, $max_rating_id, $max_movie_id+1);

    my $last_movie_id = -1;
    for my $rating ( @ratings ) {
        (my $custId, my $movieId, my $rating) = @{ $rating };
        if( $last_movie_id != $movieId ) {
            set_Movies($movieId, 0, 0); # RatingCount = 0, RatingSum = 0
            $last_movie_id = $movieId;
        }
        set_Ratings($movieId, $custId, $rating);
    }

warn "calc metrics...";

    CalcMetrics();

warn "calc features...";

    CalcFeatures();

warn "processed";

}

sub predict_rating {
    my $self = shift;
    my $movieId = shift;
    my $custId = shift;
    PredictRating($movieId, $custId);
}

1;

__END__