Description

Returns the 2-dimensional maximum distance between two geometries, in projected units. The maximum distance always occurs between two vertices. This is the length of the line returned by ST_LongestLine.

If only one geometry is provided, or g1 and g2 are the same geometry, returns the distance between the two vertices farthest apart in that geometry.

Availability: 1.5.0

Enhanced: 3.7.0 - support for a single geometry input.

Examples

Maximum distance between a point and lines.

SELECT ST_MaxDistance('POINT(0 0)'::geometry, 'LINESTRING ( 2 0,0 2 )'::geometry);

2

Figure

SELECT ST_MaxDistance('POINT(0 0)'::geometry, 'LINESTRING ( 2 2,2 2 )'::geometry);

2.82842712474619

Figure

Maximum distance between vertices of a single geometry.

SELECT ST_MaxDistance('POLYGON ((10 10,10 0,0 0,10 10))'::geometry);

 14.142135623730951

Figure

See Also

ST_Distance, ST_LongestLine, ST_DFullyWithin