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| |
| # ST_Angle |
| |
| Introduction: Computes and returns 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](ST_Degrees.md). |
| |
|  |
| |
| Format: `ST_Angle(p1, p2, p3, p4) | ST_Angle(p1, p2, p3) | ST_Angle(line1, line2)` |
| |
| Return type: `Double` |
| |
| Since: `v1.5.0` |
| |
| SQL Example |
| |
| ```sql |
| 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 |
| ``` |
| |
| SQL Example |
| |
| ```sql |
| SELECT ST_Angle(ST_GeomFromWKT('POINT (1 1)'), ST_GeomFromWKT('POINT (0 0)'), ST_GeomFromWKT('POINT(3 2)')) |
| ``` |
| |
| Output: |
| |
| ``` |
| 0.19739555984988044 |
| ``` |
| |
| SQL Example |
| |
| ```sql |
| SELECT ST_Angle(ST_GeomFromWKT('LINESTRING (0 0, 1 1)'), ST_GeomFromWKT('LINESTRING (0 0, 3 2)')) |
| ``` |
| |
| Output: |
| |
| ``` |
| 0.19739555984988044 |
| ``` |
