ST_AZIMUTH

Introduced or updated: v1.2.911

Returns the azimuth in radians of the line segment from one Point to another, measured clockwise from the positive Y-axis (north). Returns NULL if the two points are identical.

Syntax

ST_AZIMUTH(<point1>, <point2>)

Arguments

Arguments	Description
<point1>	A GEOMETRY expression of type Point (origin).
<point2>	A GEOMETRY expression of type Point (target).

note

• Both arguments must be Point geometries. Other types produce an error.

Return Type

Double (nullable).

Examples

-- Due north (along positive Y-axis): 0 radians
SELECT ST_AZIMUTH(TO_GEOMETRY('POINT(0 0)'), TO_GEOMETRY('POINT(0 1)'));

┌────────┐
│ result │
├────────┤
│ 0.0    │
└────────┘

-- Due east: π/2 radians
SELECT ST_AZIMUTH(TO_GEOMETRY('POINT(0 0)'), TO_GEOMETRY('POINT(1 0)'));

┌─────────────┐
│    result   │
├─────────────┤
│ 1.570796327 │
└─────────────┘

-- Due south: π radians
SELECT ST_AZIMUTH(TO_GEOMETRY('POINT(0 1)'), TO_GEOMETRY('POINT(0 0)'));

┌─────────────┐
│    result   │
├─────────────┤
│ 3.141592654 │
└─────────────┘

-- Identical points: NULL
SELECT ST_AZIMUTH(TO_GEOMETRY('POINT(0 0)'), TO_GEOMETRY('POINT(0 0)'));

┌────────┐
│ result │
├────────┤
│ NULL   │
└────────┘