Devuelve la trayectoria o el área atravesada

trajectory(tpoint,unary_union boolean=false) → geo
traversedArea(tgeo,unary_union boolean=false) → geo

Esta función es equivalente a getValues para los valores temporales alphanuméricos. El último argumento indica si se aplica la función PostGIS ST_UnaryUnion para eliminar geometrías redundantes en el resultado. Tenga en cuenta que establecer este argumento como verdadero implica un alto consumo computacional.

SELECT ST_AsText(trajectory(tgeompoint '[Point(0 0)@2001-01-01, Point(0 1)@2001-01-02,
  Point(0 0)@2001-01-03]'));
-- LINESTRING(0 0,0 1,0 0)
SELECT ST_AsText(trajectory(tgeompoint '[Point(0 0)@2001-01-01, Point(0 1)@2001-01-02,
  Point(0 0)@2001-01-03]', true));
-- LINESTRING(0 0,0 1)
SELECT ST_AsText(trajectory(tgeompoint '{[Point(0 0)@2001-01-01, Point(0 1)@2001-01-02),
  [Point(0 1)@2001-01-03, Point(0 0)@2001-01-04)}'));
-- LINESTRING(0 0,0 1)
SELECT ST_AsText(trajectory(tgeompoint 'Interp=Step;{[Point(0 0)@2001-01-01,
  Point(0 1)@2001-01-02], [Point(0 1)@2001-01-03, Point(1 1)@2001-01-04]}'));
-- MULTIPOINT((0 0),(1 1),(0 1))

SELECT ST_AsText(traversedArea(tgeometry '[Point(1 1)@2001-01-01,
  Linestring(1 1,2 2)@2001-01-02, Point(1 1)@2001-01-03]'));
-- GEOMETRYCOLLECTION(POINT(1 1),LINESTRING(1 1,2 2))
SELECT ST_AsText(traversedArea(tgeometry '[Point(1 1)@2001-01-01,
  Linestring(1 1,2 2)@2001-01-02, Point(1 1)@2001-01-03]', true));
-- LINESTRING(1 1,2 2)

Devuelve el centroide como un punto temporal

centroid(tgeo) → tpoint
centroid(tgeography,spheroid boolean=true) → tgeogpoint

Para geografías, el cálculo se realiza en el esferoide WGS 84 por defecto. Si el último argumento es falso, se utiliza un cálculo esférico más rápido.

SELECT asText(centroid(tgeometry '[Point(1 1)@2001-01-01, Linestring(1 1,3 3)@2001-01-02,
  Polygon((1 1,4 4,7 1,1 1))@2001-01-03]'));
-- Interp=Step;[POINT(1 1)@2001-01-01, POINT(2 2)@2001-01-02, POINT(4 2)@2001-01-03]
SELECT asText(centroid(tgeography '[MultiPoint(1 1,4 4,7 1)@2001-01-01,
  Polygon((1 1,4 4,7 1,1 1))@2001-01-02]'),6);
-- Interp=Step;[POINT(4 2.001727)@2001-01-01, POINT(4 2.001727)@2001-01-02]
SELECT asText(centroid(tgeography '{Linestring(0 0,0 1,1 1)@2001-01-01}', false), 6);
-- {POINT(0.249967 0.750007)@2001-01-01}

Devuelve los valores de las coordenadas X/Y/Z como un número flotante temporal

getX(tpoint) → tfloat
getY(tpoint) → tfloat
getZ(tpoint) → tfloat

SELECT getX(tgeompoint '{Point(1 2)@2001-01-01, Point(3 4)@2001-01-02,
  Point(5 6)@2001-01-03}');
-- {1@2001-01-01, 3@2001-01-02, 5@2001-01-03}
SELECT getX(tgeogpoint 'Interp=Step;
  [Point(1 2 3)@2001-01-01, Point(4 5 6)@2001-01-02, Point(7 8 9)@2001-01-03]');
-- Interp=Step;[1@2001-01-01, 4@2001-01-02, 7@2001-01-03]
SELECT getY(tgeompoint '{Point(1 2)@2001-01-01, Point(3 4)@2001-01-02,
  Point(5 6)@2001-01-03}');
-- {2@2001-01-01, 4@2001-01-02, 6@2001-01-03}
SELECT getY(tgeogpoint 'Interp=Step;
  [Point(1 2 3)@2001-01-01, Point(4 5 6)@2001-01-02, Point(7 8 9)@2001-01-03]');
-- Interp=Step;[2@2001-01-01, 5@2001-01-02, 8@2001-01-03]
SELECT getZ(tgeompoint '{Point(1 2)@2001-01-01, Point(3 4)@2001-01-02,
  Point(5 6)@2001-01-03}');
-- The temporal point must have Z dimension
SELECT getZ(tgeogpoint 'Interp=Step;
  [Point(1 2 3)@2001-01-01, Point(4 5 6)@2001-01-02, Point(7 8 9)@2001-01-03]');
-- Interp=Step;[3@2001-01-01, 6@2001-01-02, 9@2001-01-03]

Devuelve verdadero si el punto temporal no se auto-intersecta espacialmente

isSimple(tpoint) → boolean

Nótese que un punto temporal de conjunto de secuencias es simple si cada una de las secuencias que lo componen es simple.

SELECT isSimple(tgeompoint '[Point(0 0)@2001-01-01, Point(1 1)@2001-01-02,
  Point(0 0)@2001-01-03]');
-- false
SELECT isSimple(tgeompoint '[Point(0 0 0)@2001-01-01, Point(1 1 1)@2001-01-02,
  Point(2 0 2)@2001-01-03, Point(0 0 0)@2001-01-04]');
-- false
SELECT isSimple(tgeompoint '{[Point(0 0 0)@2001-01-01, Point(1 1 1)@2001-01-02],
  [Point(1 1 1)@2001-01-03, Point(0 0 0)@2001-01-04]}');
-- true

Devuelve la longitud atravesada por el punto temporal

length(tpoint) → float
length(geo) → float
length({geography,tgeogpoint},spheroid boolean=true) → float

La función length devuelve la longitud de una geometría o de una geografía, la de una geografía en metros sobre el esferoide, como la función ST_Length de PostGIS. Si el último argumento es falso, se utiliza un cálculo esférico más rápido.

SELECT length(tgeompoint '[Point(0 0 0)@2001-01-01, Point(1 1 1)@2001-01-02]');
-- 1.73205080756888
SELECT length(tgeompoint '[Point(0 0 0)@2001-01-01, Point(1 1 1)@2001-01-02,
  Point(0 0 0)@2001-01-03]');
-- 3.46410161513775
SELECT length(tgeompoint 'Interp=Step;
  [Point(0 0 0)@2001-01-01, Point(1 1 1)@2001-01-02, Point(0 0 0)@2001-01-03]');
-- 0
SELECT length(geometry 'Linestring(0 0,3 4)');
-- 5
SELECT round(length(geography 'Linestring(4.35 50.85,4.40 50.85)'), 6);
-- 3521.188745
SELECT round(length(tgeogpoint '[Point(0 1)@2001-01-01, Point(0 2)@2001-01-02]',
  false), 3);
-- 111195.08

Devuelve la longitud acumulada atravesada por el punto temporal

cumulativeLength(tpoint) → tfloatSeq
cumulativeLength(tgeogpoint,spheroid boolean=true) → tfloatSeq

Para geografías, el cálculo se realiza en el esferoide WGS 84 por defecto. Si el último argumento es falso, se utiliza un cálculo esférico más rápido.

SELECT round(cumulativeLength(tgeompoint '{[Point(0 0)@2001-01-01, Point(1 1)@2001-01-02,
  Point(1 0)@2001-01-03], [Point(1 0)@2001-01-04, Point(0 0)@2001-01-05]}'), 6);
-- {[0@2001-01-01, 1.414214@2001-01-02, 2.414214@2001-01-03],
  [2.414214@2001-01-04, 3.414214@2001-01-05]}
SELECT cumulativeLength(tgeompoint 'Interp=Step;
  [Point(0 0 0)@2001-01-01, Point(1 1 1)@2001-01-02, Point(0 0 0)@2001-01-03]');
-- Interp=Step;[0@2001-01-01, 0@2001-01-03]
SELECT round(cumulativeLength(tgeogpoint '[Point(0 1)@2001-01-01, Point(0 2)@2001-01-02]',
  false), 3);
-- [0@2001-01-01, 111195.08@2001-01-02]

Devuelve la velocidad del punto temporal en unidades por segundo

speed(tpoint) → tfloatSeqSet
speed(tgeogpoint,spheroid boolean=true) → tfloatSeqSet

El punto temporal debe tener interpolación linear. Para geografías, el cálculo se realiza en el esferoide WGS 84 por defecto. Si el último argumento es falso, se utiliza un cálculo esférico más rápido.

SELECT speed(tgeompoint '{[Point(0 0)@2001-01-01, Point(1 1)@2001-01-02,
  Point(1 0)@2001-01-03], [Point(1 0)@2001-01-04, Point(0 0)@2001-01-05]}') * 3600 * 24;
/* Interp=Step;{[1.4142135623731@2001-01-01, 1@2001-01-02, 1@2001-01-03],
   [1@2001-01-04, 1@2001-01-05]} */
SELECT speed(tgeompoint 'Interp=Step;
  [Point(0 0)@2001-01-01, Point(1 1)@2001-01-02, Point(1 0)@2001-01-03]');
-- ERROR:  The temporal value must have linear interpolation
SELECT round(speed(tgeogpoint '[Point(0 1)@2001-01-01, Point(0 2)@2001-01-02]',
  false), 6);
-- Interp=Step;[1.28698@2001-01-01, 1.28698@2001-01-02]

Devuelve el centroide ponderado en el tiempo

twCentroid(tgeompoint) → point

SELECT ST_AsText(twCentroid(tgeompoint '{[Point(0 0 0)@2001-01-01,
  Point(0 1 1)@2001-01-02, Point(0 1 1)@2001-01-03, Point(0 0 0)@2001-01-04)}'));
-- POINT Z (0 0.666666666666667 0.666666666666667)

Devuelve la dirección, es decir, el acimut entre las ubicaciones inicial y final

direction(tpoint) → float

El resultado se expresa en radianes. Es NULL si solo hay una ubicación o si las ubicaciones inicial y final son iguales.

SELECT round(degrees(direction(tgeompoint '[Point(0 0)@2001-01-01,
  Point(-1 -1)@2001-01-02, Point(1 1)@2001-01-03]'))::numeric, 6);
-- 45.000000
SELECT direction(tgeompoint '{[Point(0 0 0)@2001-01-01, Point(0 1 1)@2001-01-02,
  Point(0 1 1)@2001-01-03, Point(0 0 0)@2001-01-04)}');
-- NULL

Devuelve el acimut temporal

azimuth(tpoint) → tfloat

El resultado se expresa en radianes. El azimut es indefinido cuando dos localizaciones sucesivas son iguales y en este caso se añade una brecha de tempo.

SELECT round(degrees(azimuth(tgeompoint '[Point(0 0 0)@2001-01-01,
  Point(1 1 1)@2001-01-02, Point(1 1 1)@2001-01-03, Point(0 0 0)@2001-01-04)')));
-- Interp=Step;{[45@2001-01-01, 45@2001-01-02], [225@2001-01-03, 225@2001-01-04)}

Devuelve la diferencia angular temporal

angularDifference(tpoint) → tfloat

El resultado se expresa en grados.

SELECT round(angularDifference(tgeompoint '[Point(1 1)@2001-01-01, Point(2 2)@2001-01-02,
  Point(1 1)@2001-01-03]'), 3);
-- {0@2001-01-01, 180@2001-01-02, 0@2001-01-03}
SELECT round(degrees(angularDifference(tgeompoint '{[Point(1 1)@2001-01-01,
  Point(2 2)@2001-01-02], [Point(2 2)@2001-01-03, Point(1 1)@2001-01-04]}')), 3);
-- {0@2001-01-01, 0@2001-01-02, 0@2001-01-03, 0@2001-01-04}

Devuelve el rumbo temporal

bearing({tpoint,point},{tpoint,point}) → tfloat

Nótese que esta función no acepta dos puntos geográficos temporales.

SELECT degrees(bearing(tgeompoint '[Point(1 1)@2001-01-01, Point(3 3)@2001-01-03]',
  geometry 'Point(2 2)'));
-- [45@2001-01-01, 0@2001-01-02, 225@2001-01-03]
SELECT round(degrees(bearing(tgeompoint '[Point(0 0)@2001-01-01, Point(2 0)@2001-01-03]',
  tgeompoint '[Point(2 1)@2001-01-01, Point(0 1)@2001-01-03]')), 3);
--  [63.435@2001-01-01, 0@2001-01-02, 296.565@2001-01-03]
SELECT round(degrees(bearing(tgeompoint '[Point(2 1)@2001-01-01, Point(0 1)@2001-01-03]',
  tgeompoint '[Point(0 0)@2001-01-01, Point(2 0)@2001-01-03]')), 3);
-- [243.435@2001-01-01, 116.565@2001-01-03]