Return the smallest distance ever

{geo,npoint,tnpoint} |=| {geo,npoint,tnpoint} → float

The operator |=| can be used for doing nearest neightbor searches using a GiST or an SP-GiST index (see the section called “Indexing”).

SELECT tnpoint '[NPoint(2, 0.3)@2001-01-01, NPoint(2, 0.7)@2001-01-02]' |=|
   geometry 'SRID=5676;Linestring(50 50,55 55)';
-- 31.69220882252415
SELECT tnpoint '[NPoint(2, 0.3)@2001-01-01, NPoint(2, 0.7)@2001-01-02]' |=|
  npoint 'NPoint(1, 0.5)';
-- 19.49691305292373
SELECT tnpoint '[NPoint(2, 0.3)@2001-01-01, NPoint(2, 0.7)@2001-01-02]' |=|
  tnpoint '[NPoint(1, 0.3)@2001-01-01, NPoint(1, 0.7)@2001-01-02]';
-- 5.231180723735304

Return the instant of the first temporal network point at which the two arguments are at the nearest distance

nearestApproachInstant({geo,npoint,tnpoint},{geo,npoint,tnpoint}) → tnpoint

SELECT nearestApproachInstant(tnpoint '[NPoint(2, 0.3)@2001-01-01,
  NPoint(2, 0.7)@2001-01-02]', geometry 'Linestring(50 50,55 55)');
-- NPoint(2,0.349928)@2001-01-01 02:59:44.402905+01
SELECT nearestApproachInstant(tnpoint '[NPoint(2, 0.3)@2001-01-01,
  NPoint(2, 0.7)@2001-01-02]', npoint 'NPoint(1, 0.5)');
-- NPoint(2,0.592181)@2001-01-01 17:31:51.080405+01

Return the line connecting the nearest approach point between the two arguments

shortestLine({geo,npoint,tpoint},{geo,npoint,tpoint}) → geometry

The function will only return the first line that it finds if there are more than one

SELECT ST_AsText(shortestLine(tnpoint '[NPoint(2, 0.3)@2001-01-01,
  NPoint(2, 0.7)@2001-01-02]', geometry 'Linestring(50 50,55 55)'));
-- LINESTRING(50.7960725266492 48.8266286733015,50 50)
SELECT ST_AsText(shortestLine(tnpoint '[NPoint(2, 0.3)@2001-01-01,
  NPoint(2, 0.7)@2001-01-02]', npoint 'NPoint(1, 0.5)'));
-- LINESTRING(77.0902838115125 66.6659083092593,90.8134936900394 46.4385792121146)

Return the temporal distance

tnpoint <-> tnpoint → tfloat

SELECT tnpoint '[NPoint(1, 0.3)@2001-01-01, NPoint(1, 0.5)@2001-01-03]' <->
  npoint 'NPoint(1, 0.2)';
-- [2.34988300875063@2001-01-02 00:00:00+01, 2.34988300875063@2001-01-03 00:00:00+01]
SELECT tnpoint '[NPoint(1, 0.3)@2001-01-01, NPoint(1, 0.5)@2001-01-03]' <->
  geometry 'Point(50 50)';
-- [25.0496666945044@2001-01-01 00:00:00+01, 26.4085688426232@2001-01-03 00:00:00+01]
SELECT tnpoint '[NPoint(1, 0.3)@2001-01-01, NPoint(1, 0.5)@2001-01-03]' <->
  tnpoint '[NPoint(1, 0.3)@2001-01-02, NPoint(1, 0.5)@2001-01-04]'
-- [2.34988300875063@2001-01-02 00:00:00+01, 2.34988300875063@2001-01-03 00:00:00+01]