ST_CPAWithin — 测试两个轨迹的最接近点是否在指定距离内。
boolean
ST_CPAWithin
(
geometry
track1
, geometry
track2
, float8
dist
)
;
测试两个移动对象是否曾经比指定距离更近。
输入必须是由检查的有效轨迹 ST_IsValidTrajectory 。如果轨迹在其M范围内不重叠,则返回FALSE。
可用性:2.2.0
This function supports 3d and will not drop the z-index.
WITH inp AS ( SELECT
ST_AddMeasure('LINESTRING Z (0 0 0, 10 0 5)'::geometry,
extract(epoch from '2015-05-26 10:00'::timestamptz),
extract(epoch from '2015-05-26 11:00'::timestamptz)
) a,
ST_AddMeasure('LINESTRING Z (0 2 10, 12 1 2)'::geometry,
extract(epoch from '2015-05-26 10:00'::timestamptz),
extract(epoch from '2015-05-26 11:00'::timestamptz)
) b
)
SELECT ST_CPAWithin(a,b,2), ST_DistanceCPA(a,b) distance FROM inp;
st_cpawithin | distance
--------------+------------------
t | 1.96521473776207