ST_Angle

Introduction: Compute and return the angle between two vectors represented by the provided points or linestrings.

There are three variants possible for ST_Angle:

ST_Angle(point1: Geometry, point2: Geometry, point3: Geometry, point4: Geometry)

Computes the angle formed by vectors represented by point1 - point2 and point3 - point4

ST_Angle(point1: Geometry, point2: Geometry, point3: Geometry)

Computes the angle formed by vectors represented by point2 - point1 and point2 - point3

ST_Angle(line1: Geometry, line2: Geometry)

Computes the angle formed by vectors S1 - E1 and S2 - E2, where S and E denote start and end points respectively

Note

If any other geometry type is provided, ST_Angle throws an IllegalArgumentException. Additionally, if any of the provided geometry is empty, ST_Angle throws an IllegalArgumentException.

Note

If a 3D geometry is provided, ST_Angle computes the angle ignoring the z ordinate, equivalent to calling ST_Angle for corresponding 2D geometries.

Tip

ST_Angle returns the angle in radian between 0 and 2\Pi. To convert the angle to degrees, use ST_Degrees.

Format: ST_Angle(p1, p2, p3, p4) | ST_Angle(p1, p2, p3) | ST_Angle(line1, line2)

Since: v1.5.0

Example:

SELECT ST_Angle(ST_GeomFromWKT('POINT(0 0)'), ST_GeomFromWKT('POINT (1 1)'), ST_GeomFromWKT('POINT(1 0)'), ST_GeomFromWKT('POINT(6 2)'))

Output:

0.4048917862850834

Example:

SELECT ST_Angle(ST_GeomFromWKT('POINT (1 1)'), ST_GeomFromWKT('POINT (0 0)'), ST_GeomFromWKT('POINT(3 2)'))

Output:

0.19739555984988044

Example:

SELECT ST_Angle(ST_GeomFromWKT('LINESTRING (0 0, 1 1)'), ST_GeomFromWKT('LINESTRING (0 0, 3 2)'))

Output:

0.19739555984988044