Capítulo 8. Tipos temporales geométricos (Parte 2)

Restringir a (al complemento de) una geometría, un lapso Z y/o un período

atGeometry(tgeom,geometry[,zspan]) → tgeom

minusGeometry(tgeom,geometry[,zspan]) → tgeom

La geometría debe ser 2D y el cálculo con respecto a ella se realiza en 2D. El resultado conserva la dimensión Z del punto temporal, si existe.

SELECT asText(atGeometry(tgeompoint '[Point(0 0)@2001-01-01, Point(3 3)@2001-01-04)',
  geometry 'Polygon((1 1,1 2,2 2,2 1,1 1))'));
-- {"[POINT(1 1)@2001-01-02, POINT(2 2)@2001-01-03]"}
SELECT astext(atGeometry(tgeompoint '[Point(0 0 0)@2001-01-01, Point(4 4 4)@2001-01-05]',
  geometry 'Polygon((1 1,1 2,2 2,2 1,1 1))'));
-- {[POINT Z (1 1 1)@2001-01-02, POINT Z (2 2 2)@2001-01-03]}
SELECT asText(atGeometry(tgeompoint '[Point(1 1 1)@2001-01-01, Point(3 1 1)@2001-01-03,
  Point(3 1 3)@2001-01-05]', 'Polygon((2 0,2 2,2 4,4 0,2 0))', '[0,2]'));
-- {[POINT Z (2 1 1)@2001-01-02, POINT Z (3 1 1)@2001-01-03, POINT Z (3 1 2)@2001-01-04]}
SELECT asText(atGeometry(tgeometry 'Linestring(1 1,10 1)@2001-01-01', 
  'Polygon((0 0,0 5,5 5,5 0,0 0))'));
-- LINESTRING(1 1,5 1)@2001-01-01

SELECT asText(minusGeometry(tgeompoint '[Point(0 0)@2001-01-01, Point(3 3)@2001-01-04)',
  geometry 'Polygon((1 1,1 2,2 2,2 1,1 1))'));
/* {[POINT(0 0)@2001-01-01, POINT(1 1)@2001-01-02), (POINT(2 2)@2001-01-03,
   POINT(3 3)@2001-01-04)} */
SELECT astext(minusGeometry(tgeompoint '[Point(0 0 0)@2001-01-01,
  Point(4 4 4)@2001-01-05]', geometry 'Polygon((1 1,1 2,2 2,2 1,1 1))'));
/* {[POINT Z (0 0 0)@2001-01-01, POINT Z (1 1 1)@2001-01-02),
   (POINT Z (2 2 2)@2001-01-03, POINT Z (4 4 4)@2001-01-05]} */
SELECT asText(minusGeometry(tgeompoint '[Point(1 1 1)@2001-01-01, Point(3 1 1)@2001-01-03,
  Point(3 1 3)@2001-01-05]', 'Polygon((2 0,2 2,2 4,4 0,2 0))', '[0,2]'));
/* {[POINT Z (1 1 1)@2001-01-01, POINT Z (2 1 1)@2001-01-02),
    (POINT Z (3 1 2)@2001-01-04, POINT Z (3 1 3)@2001-01-05]} */
SELECT asText(minusGeometry(tgeometry 'Linestring(1 1,10 1)@2001-01-01', 
  'Polygon((0 0,0 5,5 5,5 0,0 0))'));
-- LINESTRING(5 1,10 1)@2001-01-01

Restringir a (al complemento de) un stbox

atStbox(tgeom,stbox,borderInc bool=true) → tgeompoint

minusStbox(tgeom,stbox,borderInc bool=true) → tgeompoint

El tercer argumento opcional se utiliza para mosaicos multidimensionales (ver “Mosaicos multidimensionales”) para excluir el borde superior de los mosaicos cuando un valor temporal se divide en varios mosaicos, de modo que todos los fragmentos de la geometría temporal sean exclusivos.

SELECT asText(atStbox(tgeompoint '[Point(0 0)@2001-01-01, Point(3 3)@2001-01-04)',
  stbox 'STBOX XT(((0,0),(2,2)),[2001-01-02, 2001-01-04])'));
-- {[POINT(1 1)@2001-01-02, POINT(2 2)@2001-01-03]}
SELECT asText(atStbox(tgeompoint '[Point(1 1 1)@2001-01-01, Point(3 3 3)@2001-01-03,
  Point(3 3 2)@2001-01-04, Point(3 3 7)@2001-01-09]', stbox 'STBOX Z((2,2,2),(3,3,3))'));
/* {[POINT Z (2 2 2)@2001-01-02, POINT Z (3 3 3)@2001-01-03, POINT Z (3 3 2)@2001-01-04,
  POINT Z (3 3 3)@2001-01-05]} */
SELECT asText(atStbox(tgeometry '[Point(1 1)@2001-01-01, Linestring(1 1,3 3)@2001-01-03,
  Point(2 2)@2001-01-04, Linestring(3 3,4 4)@2001-01-09]', stbox 'STBOX X((2,2),(3,3))'));
-- {[LINESTRING(2 2,3 3)@2001-01-03, POINT(2 2)@2001-01-04, POINT(3 3)@2001-01-09]}

SELECT asText(minusStbox(tgeompoint '[Point(1 1)@2001-01-01, Point(4 4)@2001-01-04)',
  stbox 'STBOX XT(((1,1),(2,2)),[2001-01-03,2001-01-04])'));
-- {(POINT(2 2)@2001-01-02, POINT(3 3)@2001-01-03)}
SELECT asText(minusStbox(tgeompoint '[Point(1 1 1)@2001-01-01, Point(3 3 3)@2001-01-03,
  Point(3 3 2)@2001-01-04, Point(3 3 7)@2001-01-09]', stbox 'STBOX Z((2,2,2),(3,3,3))'));
/* {[POINT Z (1 1 1)@2001-01-01, POINT Z (2 2 2)@2001-01-02), 
    (POINT Z (3 3 3)@2001-01-05, POINT Z (3 3 7)@2001-01-09]} */
SELECT asText(minusStbox(tgeometry '[Point(1 1)@2001-01-01, 
  Linestring(1 1,3 3)@2001-01-03, Point(2 2)@2001-01-04, 
  Linestring(1 1,4 4)@2001-01-09]', stbox 'STBOX X((2,2),(3,3))'));
/* {[POINT(1 1)@2001-01-01, LINESTRING(1 1,2 2)@2001-01-03, 
   LINESTRING(1 1,2 2)@2001-01-04),[MULTILINESTRING((1 1,2 2),(3 3,4 4))@2001-01-09]} */