presto-ml/src/main/java/io/prestosql/plugin/ml/MLFeaturesFunctions.java/Features2/features
class Features2:        @SqlType(MAP_BIGINT_DOUBLE)
        public Block features(@SqlType(StandardTypes.DOUBLE) double f1, @SqlType(StandardTypes.DOUBLE) double f2)
        {
            return featuresHelper(pageBuilder, f1, f2);
        }