SELECT array_to_skewness('{}'::float[]); array_to_skewness ------------------- (1 row) SELECT array_to_skewness('{1,1,5,2,0}'::smallint[]); array_to_skewness ------------------- 1.017952296026958 (1 row) SELECT array_to_skewness('{1,1,5,2,0}'::integer[]); array_to_skewness ------------------- 1.017952296026958 (1 row) SELECT array_to_skewness('{1,1,5,2,0}'::bigint[]); array_to_skewness ------------------- 1.017952296026958 (1 row) SELECT array_to_skewness('{1,1,5,2,0}'::real[]); array_to_skewness ------------------- 1.017952296026958 (1 row) SELECT array_to_skewness('{1,1,5,2,0}'::float[]); array_to_skewness ------------------- 1.017952296026958 (1 row) SELECT array_to_skewness('{1,1,5,2,0}'::text[]); ERROR: Skewness subject must be SMALLINT, INTEGER, BIGINT, REAL, or DOUBLE PRECISION values