public FieldAwareFactorizationMachinePredictionTransformer(IHostEnvironment host, FieldAwareFactorizationMachinePredictor model, ISchema trainSchema,
string[] featureColumns, float threshold = 0f, string thresholdColumn = DefaultColumnNames.Score)
: base(Contracts.CheckRef(host, nameof(host)).Register(nameof(FieldAwareFactorizationMachinePredictionTransformer)), model, trainSchema)
{
Host.CheckNonEmpty(thresholdColumn, nameof(thresholdColumn));
_threshold = threshold;
_thresholdColumn = thresholdColumn;
Host.CheckValue(featureColumns, nameof(featureColumns));
int featCount = featureColumns.Length;
Host.Check(featCount >= 0, "Empty features column.");
FeatureColumns = featureColumns;
FeatureColumnTypes = new ColumnType[featCount];
int i = 0;
foreach (var feat in featureColumns)
{
if (!trainSchema.TryGetColumnIndex(feat, out int col))
{
throw Host.ExceptSchemaMismatch(nameof(featureColumns), RoleMappedSchema.ColumnRole.Feature.Value, feat);
}
FeatureColumnTypes[i++] = trainSchema.GetColumnType(col);
}
BindableMapper = ScoreUtils.GetSchemaBindableMapper(Host, model);
var schema = GetSchema();
var args = new BinaryClassifierScorer.Arguments {
Threshold = _threshold, ThresholdColumn = _thresholdColumn
};
_scorer = new BinaryClassifierScorer(Host, args, new EmptyDataView(Host, trainSchema), BindableMapper.Bind(Host, schema), schema);
}
