Added basic support for float4 arrays

sql/vector.sql

@@ -34,6 +34,9 @@ CREATE TYPE vector (
 CREATE FUNCTION l2_distance(vector, vector) RETURNS float8
 	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
 
+CREATE FUNCTION float4_l2_distance(float4[], float4[]) RETURNS float8
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
 CREATE FUNCTION inner_product(vector, vector) RETURNS float8
 	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
 
@@ -84,6 +87,9 @@ CREATE FUNCTION vector_cmp(vector, vector) RETURNS int4
 CREATE FUNCTION vector_l2_squared_distance(vector, vector) RETURNS float8
 	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
 
+CREATE FUNCTION float4_l2_squared_distance(float4[], float4[]) RETURNS float8
+	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
+
 CREATE FUNCTION vector_negative_inner_product(vector, vector) RETURNS float8
 	AS 'MODULE_PATHNAME' LANGUAGE C IMMUTABLE STRICT PARALLEL SAFE;
 
@@ -164,6 +170,11 @@ CREATE OPERATOR <-> (
 	COMMUTATOR = '<->'
 );
 
+CREATE OPERATOR <-> (
+	LEFTARG = float4[], RIGHTARG = float4[], PROCEDURE = float4_l2_distance,
+	COMMUTATOR = '<->'
+);
+
 CREATE OPERATOR <#> (
 	LEFTARG = vector, RIGHTARG = vector, PROCEDURE = vector_negative_inner_product,
 	COMMUTATOR = '<#>'
@@ -280,6 +291,11 @@ CREATE OPERATOR CLASS vector_l2_ops
 	OPERATOR 1 <-> (vector, vector) FOR ORDER BY float_ops,
 	FUNCTION 1 vector_l2_squared_distance(vector, vector);
 
+CREATE OPERATOR CLASS float4_l2_ops
+	FOR TYPE float4[] USING hnsw AS
+	OPERATOR 1 <-> (float4[], float4[]) FOR ORDER BY float_ops,
+	FUNCTION 1 float4_l2_squared_distance(float4[], float4[]);
+
 CREATE OPERATOR CLASS vector_ip_ops
 	FOR TYPE vector USING hnsw AS
 	OPERATOR 1 <#> (vector, vector) FOR ORDER BY float_ops,