view release on metacpan or  search on metacpan

lib/AI/XGBoost/CAPI.pm  view on Meta::CPAN

    my $out_len                       = 0;
    my $out_result                    = 0;
    my $ffi                           = FFI::Platypus->new();
    my $number_of_features            = scalar @$feature_names;
    my $array_of_opaque_feature_names = [ map { $ffi->cast( string => "opaque", $_ ) } @$feature_names ];
    my $array_of_opaque_feature_types = [ map { $ffi->cast( string => "opaque", $_ ) } @$feature_types ];
    _CheckCall(
                AI::XGBoost::CAPI::RAW::XGBoosterDumpModelWithFeatures( $booster, $number_of_features,
                                                                        $array_of_opaque_feature_names,
                                                                        $array_of_opaque_feature_types,
                                                                        $with_stats, \$out_len, \$out_result
                )
    );
    $out_result = $ffi->cast( opaque => "opaque[$out_len]", $out_result );
    return [ map { $ffi->cast( opaque => "string", $_ ) } @$out_result ];
}

sub XGBoosterDumpModelExWithFeatures {
    my ( $booster, $feature_names, $feature_types, $with_stats, $format ) = @_;
    my $out_len                       = 0;
    my $out_result                    = 0;
    my $ffi                           = FFI::Platypus->new();
    my $number_of_features            = scalar @$feature_names;
    my $array_of_opaque_feature_names = [ map { $ffi->cast( string => "opaque", $_ ) } @$feature_names ];
    my $array_of_opaque_feature_types = [ map { $ffi->cast( string => "opaque", $_ ) } @$feature_types ];
    _CheckCall(
                AI::XGBoost::CAPI::RAW::XGBoosterDumpModelExWithFeatures( $booster, $number_of_features,
                                                                          $array_of_opaque_feature_names,
                                                                          $array_of_opaque_feature_types,
                                                                          $with_stats, $format, \$out_len, \$out_result
                )
    );
    $out_result = $ffi->cast( opaque => "opaque[$out_len]", $out_result );
    return [ map { $ffi->cast( opaque => "string", $_ ) } @$out_result ];
}

sub XGBoosterFree {
    my ($booster) = @_;
    _CheckCall( AI::XGBoost::CAPI::RAW::XGBoosterFree($booster) );
    return ();
}

# _CheckCall
#
#  Check return code and if necesary, launch an exception
#
sub _CheckCall {
    my ($return_code) = @_;
    if ($return_code) {
        my $error_message = AI::XGBoost::CAPI::RAW::XGBGetLastError();
        XGBoostException->throw( error => $error_message );
    }
}

1;

__END__

=pod

=encoding utf-8

=head1 NAME

AI::XGBoost::CAPI - Perl wrapper for XGBoost C API https://github.com/dmlc/xgboost

=head1 VERSION

version 0.11

=head1 SYNOPSIS

 use 5.010;
 use AI::XGBoost::CAPI qw(:all);
 
 my $dtrain = XGDMatrixCreateFromFile('agaricus.txt.train');
 my $dtest = XGDMatrixCreateFromFile('agaricus.txt.test');
 
 my ($rows, $cols) = (XGDMatrixNumRow($dtrain), XGDMatrixNumCol($dtrain));
 say "Train dimensions: $rows, $cols";
 
 my $booster = XGBoosterCreate([$dtrain]);
 
 for my $iter (0 .. 10) {
     XGBoosterUpdateOneIter($booster, $iter, $dtrain);
 }
 
 my $predictions = XGBoosterPredict($booster, $dtest);
 # say join "\n", @$predictions;
 
 XGBoosterFree($booster);
 XGDMatrixFree($dtrain);
 XGDMatrixFree($dtest);

=head1 DESCRIPTION

Perlified wrapper for the C API

=head2 Error handling

XGBoost c api functions returns some int to signal the presence/absence of error.
In this module that is achieved using Exceptions from L<Exception::Class>

=head1 FUNCTIONS

=head2 XGDMatrixCreateFromFile

Load a data matrix

Parameters:

=over 4

=item filename

the name of the file

=item silent 

whether print messages during loading