Geometric Functions and Operators
Geometric Operators
Description: Translation
Example:
```
openGauss=# SELECT box '((0,0),(1,1))' + point '(2.0,0)' AS RESULT;
result
-------------
(3,1),(2,0)
(1 row)
```
Description: Translation
Example:
```
openGauss=# SELECT box '((0,0),(1,1))' - point '(2.0,0)' AS RESULT;
result
---------------
(-1,1),(-2,0)
(1 row)
```
*
Description: Scaling out/Rotation
Example:
openGauss=# SELECT box '((0,0),(1,1))' * point '(2.0,0)' AS RESULT; result ------------- (2,2),(0,0) (1 row)/
Description: Scaling in/Rotation
Example:
openGauss=# SELECT box '((0,0),(2,2))' / point '(2.0,0)' AS RESULT; result ------------- (1,1),(0,0) (1 row)#
Description: Intersection of two figures
Example:
openGauss=# SELECT box '((1,-1),(-1,1))' # box '((1,1),(-2,-2))' AS RESULT; result --------------- (1,1),(-1,-1) (1 row)#
Description: Number of paths or polygon vertexes of a figure
Example:
openGauss=# SELECT # path'((1,0),(0,1),(-1,0))' AS RESULT; result -------- 3 (1 row)@-@
Description: Length or circumference of a figure
Example:
openGauss=# SELECT @-@ path '((0,0),(1,0))' AS RESULT; result -------- 2 (1 row)@@
Description: Center of a figure
Example:
openGauss=# SELECT @@ circle '((0,0),10)' AS RESULT; result -------- (0,0) (1 row)<->
Description: Distance between two figures
Example:
openGauss=# SELECT circle '((0,0),1)' <-> circle '((5,0),1)' AS RESULT; result -------- 3 (1 row)&&
Description: Overlaps? (One point in common makes this true.)
Example:
openGauss=# SELECT box '((0,0),(1,1))' && box '((0,0),(2,2))' AS RESULT; result -------- t (1 row)«
Description: Is strictly left of (no common horizontal coordinate)?
Example:
openGauss=# SELECT circle '((0,0),1)' << circle '((5,0),1)' AS RESULT; result -------- t (1 row)>>
Description: Is strictly right of (no common horizontal coordinate)?
Example:
openGauss=# SELECT circle '((5,0),1)' >> circle '((0,0),1)' AS RESULT; result -------- t (1 row)&<
Description: Does not extend to the right of?
Example:
openGauss=# SELECT box '((0,0),(1,1))' &< box '((0,0),(2,2))' AS RESULT; result -------- t (1 row)&>
Description: Does not extend to the left of?
Example:
openGauss=# SELECT box '((0,0),(3,3))' &> box '((0,0),(2,2))' AS RESULT; result -------- t (1 row)«|
Description: Is strictly below (no common horizontal coordinate)?
Example:
openGauss=# SELECT box '((0,0),(3,3))' <<| box '((3,4),(5,5))' AS RESULT; result -------- t (1 row)|>>
Description: Is strictly above (no common horizontal coordinate)?
Example:
openGauss=# SELECT box '((3,4),(5,5))' |>> box '((0,0),(3,3))' AS RESULT; result -------- t (1 row)&<|
Description: Does not extend above?
Example:
openGauss=# SELECT box '((0,0),(1,1))' &<| box '((0,0),(2,2))' AS RESULT; result -------- t (1 row)|&>
Description: Does not extend below?
Example:
openGauss=# SELECT box '((0,0),(3,3))' |&> box '((0,0),(2,2))' AS RESULT; result -------- t (1 row)<^
Description: Is below (allows touching)?
Example:
openGauss=# SELECT box '((0,0),(-3,-3))' <^ box '((0,0),(2,2))' AS RESULT; result -------- t (1 row)>^
Description: Is above (allows touching)?
Example:
openGauss=# SELECT box '((0,0),(2,2))' >^ box '((0,0),(-3,-3))' AS RESULT; result -------- t (1 row)?#
Description: Intersect?
Example:
openGauss=# SELECT lseg '((-1,0),(1,0))' ?# box '((-2,-2),(2,2))' AS RESULT; result -------- t (1 row)?-
Description: Is horizontal?
Example:
openGauss=# SELECT ?- lseg '((-1,0),(1,0))' AS RESULT; result -------- t (1 row)?-
Description: Are horizontally aligned?
Example:
openGauss=# SELECT point '(1,0)' ?- point '(0,0)' AS RESULT; result -------- t (1 row)?|
Description: Is vertical?
Example:
openGauss=# SELECT ?| lseg '((-1,0),(1,0))' AS RESULT; result -------- f (1 row)?|
Description: Are vertically aligned?
Example:
openGauss=# SELECT point '(0,1)' ?| point '(0,0)' AS RESULT; result -------- t (1 row)?-|
Description: Are perpendicular?
Example:
openGauss=# SELECT lseg '((0,0),(0,1))' ?-| lseg '((0,0),(1,0))' AS RESULT; result -------- t (1 row)?||
Description: Are parallel?
Example:
openGauss=# SELECT lseg '((-1,0),(1,0))' ?|| lseg '((-1,2),(1,2))' AS RESULT; result -------- t (1 row)@>
Description: Contains?
Example:
openGauss=# SELECT circle '((0,0),2)' @> point '(1,1)' AS RESULT; result -------- t (1 row)<@
Description: Contained in or on?
Example:
openGauss=# SELECT point '(1,1)' <@ circle '((0,0),2)' AS RESULT; result -------- t (1 row)~=
Description: Same as?
Example:
openGauss=# SELECT polygon '((0,0),(1,1))' ~= polygon '((1,1),(0,0))' AS RESULT; result -------- t (1 row)
Geometric Functions
area(object)
Description: Area calculation
Return type: double precision
Example:
openGauss=# SELECT area(box '((0,0),(1,1))') AS RESULT; result -------- 1 (1 row)center(object)
Description: Figure center calculation
Return type: point
Example:
openGauss=# SELECT center(box '((0,0),(1,2))') AS RESULT; result --------- (0.5,1) (1 row)diameter(circle)
Description: Circle diameter calculation
Return type: double precision
Example:
openGauss=# SELECT diameter(circle '((0,0),2.0)') AS RESULT; result -------- 4 (1 row)height(box)
Description: Vertical size of box
Return type: double precision
Example:
openGauss=# SELECT height(box '((0,0),(1,1))') AS RESULT; result -------- 1 (1 row)isclosed(path)
Description: A closed path?
Return type: Boolean
Example:
openGauss=# SELECT isclosed(path '((0,0),(1,1),(2,0))') AS RESULT; result -------- t (1 row)isopen(path)
Description: An open path?
Return type: Boolean
Example:
openGauss=# SELECT isopen(path '[(0,0),(1,1),(2,0)]') AS RESULT; result -------- t (1 row)length(object)
Description: Length calculation
Return type: double precision
Example:
openGauss=# SELECT length(path '((-1,0),(1,0))') AS RESULT; result -------- 4 (1 row)npoints(path)
Description: Number of points in a path
Return type: int
Example:
openGauss=# SELECT npoints(path '[(0,0),(1,1),(2,0)]') AS RESULT; result -------- 3 (1 row)npoints(polygon)
Description: Number of points in a polygon
Return type: int
Example:
openGauss=# SELECT npoints(polygon '((1,1),(0,0))') AS RESULT; result -------- 2 (1 row)pclose(path)
Description: Converts a path to closed.
Return type: path
Example:
openGauss=# SELECT pclose(path '[(0,0),(1,1),(2,0)]') AS RESULT; result --------------------- ((0,0),(1,1),(2,0)) (1 row)popen(path)
Description: Converts a path to open.
Return type: path
Example:
openGauss=# SELECT popen(path '((0,0),(1,1),(2,0))') AS RESULT; result --------------------- [(0,0),(1,1),(2,0)] (1 row)radius(circle)
Description: Circle radius calculation
Return type: double precision
Example:
openGauss=# SELECT radius(circle '((0,0),2.0)') AS RESULT; result -------- 2 (1 row)width(box)
Description: Horizontal size of a box
Return type: double precision
Example:
openGauss=# SELECT width(box '((0,0),(1,1))') AS RESULT; result -------- 1 (1 row)
Geometric Type Conversion Functions
box(circle)
Description: Circle to box
Return type: box
Example:
openGauss=# SELECT box(circle '((0,0),2.0)') AS RESULT; result --------------------------------------------------------------------------- (1.41421356237309,1.41421356237309),(-1.41421356237309,-1.41421356237309) (1 row)box(point, point)
Description: Points to box
Return type: box
Example:
openGauss=# SELECT box(point '(0,0)', point '(1,1)') AS RESULT; result ------------- (1,1),(0,0) (1 row)box(polygon)
Description: Polygon to box
Return type: box
Example:
openGauss=# SELECT box(polygon '((0,0),(1,1),(2,0))') AS RESULT; result ------------- (2,1),(0,0) (1 row)circle(box)
Description: Box to circle
Return type: circle
Example:
openGauss=# SELECT circle(box '((0,0),(1,1))') AS RESULT; result ------------------------------- <(0.5,0.5),0.707106781186548> (1 row)circle(point, double precision)
Description: Center and radius to circle
Return type: circle
Example:
openGauss=# SELECT circle(point '(0,0)', 2.0) AS RESULT; result ----------- <(0,0),2> (1 row)circle(polygon)
Description: Polygon to circle
Return type: circle
Example:
openGauss=# SELECT circle(polygon '((0,0),(1,1),(2,0))') AS RESULT; result ------------------------------------------- <(1,0.333333333333333),0.924950591148529> (1 row)lseg(box)
Description: Box diagonal to line segment
Return type: lseg
Example:
openGauss=# SELECT lseg(box '((-1,0),(1,0))') AS RESULT; result ---------------- [(1,0),(-1,0)] (1 row)lseg(point, point)
Description: Points to line segment
Return type: lseg
Example:
openGauss=# SELECT lseg(point '(-1,0)', point '(1,0)') AS RESULT; result ---------------- [(-1,0),(1,0)] (1 row)slope(point, point)
Description: Calculates the slope of a straight line formed by two points.
Return type: double
Example:
openGauss=# SELECT slope(point '(1,1)', point '(0,0)') AS RESULT; result -------- 1 (1 row)path(polygon)
Description: Polygon to path
Return type: path
Example:
openGauss=# SELECT path(polygon '((0,0),(1,1),(2,0))') AS RESULT; result --------------------- ((0,0),(1,1),(2,0)) (1 row)point(double precision, double precision)
Description: Points
Return type: point
Example:
openGauss=# SELECT point(23.4, -44.5) AS RESULT; result -------------- (23.4,-44.5) (1 row)point(box)
Description: Center of a box
Return type: point
Example:
openGauss=# SELECT point(box '((-1,0),(1,0))') AS RESULT; result -------- (0,0) (1 row)point(circle)
Description: Center of a circle
Return type: point
Example:
openGauss=# SELECT point(circle '((0,0),2.0)') AS RESULT; result -------- (0,0) (1 row)point(lseg)
Description: Center of a line segment
Return type: point
Example:
openGauss=# SELECT point(lseg '((-1,0),(1,0))') AS RESULT; result -------- (0,0) (1 row)point(polygon)
Description: Center of a polygon
Return type: point
Example:
openGauss=# SELECT point(polygon '((0,0),(1,1),(2,0))') AS RESULT; result ----------------------- (1,0.333333333333333) (1 row)polygon(box)
Description: Box to 4-point polygon
Return type: polygon
Example:
openGauss=# SELECT polygon(box '((0,0),(1,1))') AS RESULT; result --------------------------- ((0,0),(0,1),(1,1),(1,0)) (1 row)polygon(circle)
Description: Circle to 12-point polygon
Return type: polygon
Example:
openGauss=# SELECT polygon(circle '((0,0),2.0)') AS RESULT; result ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- ((-2,0),(-1.73205080756888,1),(-1,1.73205080756888),(-1.22464679914735e-16,2),(1,1.73205080756888),(1.73205080756888,1),(2,2.44929359829471e-16),(1.73205080756888,-0.999999999999999),(1,-1.73205080756888),(3.67394039744206e-16,-2),(-0.999999999999999,-1.73205080756888),(-1.73205080756888,-1)) (1 row)polygon(npts, circle)
Description: Circle to npts-point polygon
Return type: polygon
Example:
openGauss=# SELECT polygon(12, circle '((0,0),2.0)') AS RESULT; result ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- ((-2,0),(-1.73205080756888,1),(-1,1.73205080756888),(-1.22464679914735e-16,2),(1,1.73205080756888),(1.73205080756888,1),(2,2.44929359829471e-16),(1.73205080756888,-0.999999999999999),(1,-1.73205080756888),(3.67394039744206e-16,-2),(-0.999999999999999,-1.73205080756888),(-1.73205080756888,-1)) (1 row)polygon(path)
Description: Path to polygon
Return type: polygon
Example:
openGauss=# SELECT polygon(path '((0,0),(1,1),(2,0))') AS RESULT; result --------------------- ((0,0),(1,1),(2,0)) (1 row)