Reviewed-by: Hasko, Vladimir <vladimir.hasko@t-systems.com> Co-authored-by: Lu, Huayi <luhuayi@huawei.com> Co-committed-by: Lu, Huayi <luhuayi@huawei.com>
115 KiB
Geometric Functions and Operators
Geometric Operators
- +
For example:
1 2 3 4 5
SELECT box '((0,0),(1,1))' + point '(2.0,0)' AS RESULT; result ------------- (3,1),(2,0) (1 row)
- -
For example:
1 2 3 4 5
SELECT box '((0,0),(1,1))' - point '(2.0,0)' AS RESULT; result --------------- (-1,1),(-2,0) (1 row)
- *
Description: Scaling out/rotation
For example:
1 2 3 4 5
SELECT box '((0,0),(1,1))' * point '(2.0,0)' AS RESULT; result ------------- (2,2),(0,0) (1 row)
- /
Description: Scaling in/rotation
For example:
1 2 3 4 5
SELECT box '((0,0),(2,2))' / point '(2.0,0)' AS RESULT; result ------------- (1,1),(0,0) (1 row)
- #
Description: Point or box of intersection
For example:
1 2 3 4 5
SELECT box'((1,-1),(-1,1))' # box'((1,1),(-1,-1))' AS RESULT; result -------- (1,1),(-1,-1) (1 row)
- #
Description: Number of paths or polygon vertexs
For example:
1 2 3 4 5
SELECT # path'((1,0),(0,1),(-1,0))' AS RESULT; result -------- 3 (1 row)
- @-@
Description: Length or circumference
For example:
1 2 3 4 5
SELECT @-@ path '((0,0),(1,0))' AS RESULT; result -------- 2 (1 row)
- @@
For example:
1 2 3 4 5
SELECT @@ circle '((0,0),10)' AS RESULT; result -------- (0,0) (1 row)
- ##
Description: Closest point to first figure on second figure.
For example:
1 2 3 4 5
SELECT point '(0,0)' ## box '((2,0),(0,2))' AS RESULT; result -------- (0,0) (1 row)
- <->
Description: Distance between the two figures.
For example:
1 2 3 4 5
SELECT circle '((0,0),1)' <-> circle '((5,0),1)' AS RESULT; result -------- 3 (1 row)
- &&
Description: Overlaps? (One point in common makes this true.)
For example:
1 2 3 4 5
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)?
For example:
1 2 3 4 5
SELECT circle '((0,0),1)' << circle '((5,0),1)' AS RESULT; result -------- t (1 row)
- >>
Description: Is strictly right of (no common horizontal coordinate)?
For example:
1 2 3 4 5
SELECT circle '((5,0),1)' >> circle '((0,0),1)' AS RESULT; result -------- t (1 row)
- &<
Description: Does not extend to the right of?
For example:
1 2 3 4 5
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?
For example:
1 2 3 4 5
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)?
For example:
1 2 3 4 5
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)?
For example:
1 2 3 4 5
SELECT box '((3,4),(5,5))' |>> box '((0,0),(3,3))' AS RESULT; result -------- t (1 row)
- &<|
Description: Does not extend above?
For example:
1 2 3 4 5
SELECT box '((0,0),(1,1))' &<| box '((0,0),(2,2))' AS RESULT; result -------- t (1 row)
- |&>
Description: Does not extend below?
For example:
1 2 3 4 5
SELECT box '((0,0),(3,3))' |&> box '((0,0),(2,2))' AS RESULT; result -------- t (1 row)
- <^
Description: Is below (allows touching)?
For example:
1 2 3 4 5
SELECT box '((0,0),(-3,-3))' <^ box '((0,0),(2,2))' AS RESULT; result -------- t (1 row)
- >^
Description: Is above (allows touching)?
For example:
1 2 3 4 5
SELECT box '((0,0),(2,2))' >^ box '((0,0),(-3,-3))' AS RESULT; result -------- t (1 row)
- ?#
For example:
1 2 3 4 5
SELECT lseg '((-1,0),(1,0))' ?# box '((-2,-2),(2,2))' AS RESULT; result -------- t (1 row)
- ?-
For example:
1 2 3 4 5
SELECT ?- lseg '((-1,0),(1,0))' AS RESULT; result -------- t (1 row)
- ?-
Description: Are horizontally aligned?
For example:
1 2 3 4 5
SELECT point '(1,0)' ?- point '(0,0)' AS RESULT; result -------- t (1 row)
- ?|
For example:
1 2 3 4 5
SELECT ?| lseg '((-1,0),(1,0))' AS RESULT; result -------- f (1 row)
- ?|
Description: Are vertically aligned?
For example:
1 2 3 4 5
SELECT point '(0,1)' ?| point '(0,0)' AS RESULT; result -------- t (1 row)
- ?-|
Description: Are perpendicular?
For example:
1 2 3 4 5
SELECT lseg '((0,0),(0,1))' ?-| lseg '((0,0),(1,0))' AS RESULT; result -------- t (1 row)
- ?||
For example:
1 2 3 4 5
SELECT lseg '((-1,0),(1,0))' ?|| lseg '((-1,2),(1,2))' AS RESULT; result -------- t (1 row)
- @>
For example:
1 2 3 4 5
SELECT circle '((0,0),2)' @> point '(1,1)' AS RESULT; result -------- t (1 row)
- <@
Description: Contained in or on?
For example:
1 2 3 4 5
SELECT point '(1,1)' <@ circle '((0,0),2)' AS RESULT; result -------- t (1 row)
- ~=
For example:
1 2 3 4 5
SELECT polygon '((0,0),(1,1))' ~= polygon '((1,1),(0,0))' AS RESULT; result -------- t (1 row)
Geometric Functions
- area(object)
Return type: double precision
For example:
1 2 3 4 5
SELECT area(box '((0,0),(1,1))') AS RESULT; result -------- 1 (1 row)
- center(object)
Description: Figure center calculation
Return type: point
For example:
1 2 3 4 5
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
For example:
1 2 3 4 5
SELECT diameter(circle '((0,0),2.0)') AS RESULT; result -------- 4 (1 row)
- height(box)
Description: Vertical size of box
Return type: double precision
For example:
1 2 3 4 5
SELECT height(box '((0,0),(1,1))') AS RESULT; result -------- 1 (1 row)
- isclosed(path)
Return type: boolean
For example:
1 2 3 4 5
SELECT isclosed(path '((0,0),(1,1),(2,0))') AS RESULT; result -------- t (1 row)
- isopen(path)
Return type: boolean
For example:
1 2 3 4 5
SELECT isopen(path '[(0,0),(1,1),(2,0)]') AS RESULT; result -------- t (1 row)
- length(object)
Description: Length calculation
Return type: double precision
For example:
1 2 3 4 5
SELECT length(path '((-1,0),(1,0))') AS RESULT; result -------- 4 (1 row)
- npoints(path)
Description: Number of points in path
Return type: int
For example:
1 2 3 4 5
SELECT npoints(path '[(0,0),(1,1),(2,0)]') AS RESULT; result -------- 3 (1 row)
- npoints(polygon)
Description: Number of points in polygon
Return type: int
For example:
1 2 3 4 5
SELECT npoints(polygon '((1,1),(0,0))') AS RESULT; result -------- 2 (1 row)
- pclose(path)
Description: Converts path to closed.
Return type: path
For example:
1 2 3 4 5
SELECT pclose(path '[(0,0),(1,1),(2,0)]') AS RESULT; result --------------------- ((0,0),(1,1),(2,0)) (1 row)
- popen(path)
Description: Converts path to open.
Return type: path
For example:
1 2 3 4 5
SELECT popen(path '((0,0),(1,1),(2,0))') AS RESULT; result --------------------- [(0,0),(1,1),(2,0)] (1 row)
- radius(circle)
Description: Circle diameter calculation
Return type: double precision
For example:
1 2 3 4 5
SELECT radius(circle '((0,0),2.0)') AS RESULT; result -------- 2 (1 row)
- width(box)
Description: Horizontal size of box
Return type: double precision
For example:
1 2 3 4 5
SELECT width(box '((0,0),(1,1))') AS RESULT; result -------- 1 (1 row)
Geometric Type Conversion Functions
- box(circle)
Return type: box
For example:
1 2 3 4 5
SELECT box(circle '((0,0),2.0)') AS RESULT; result --------------------------------------------------------------------------- (1.41421356237309,1.41421356237309),(-1.41421356237309,-1.41421356237309) (1 row)
- box(point, point)
Return type: box
For example:
1 2 3 4 5
SELECT box(point '(0,0)', point '(1,1)') AS RESULT; result ------------- (1,1),(0,0) (1 row)
- box(polygon)
Return type: box
For example:
1 2 3 4 5
SELECT box(polygon '((0,0),(1,1),(2,0))') AS RESULT; result ------------- (2,1),(0,0) (1 row)
- circle(box)
Return type: circle
For example:
1 2 3 4 5
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
For example:
1 2 3 4 5
SELECT circle(point '(0,0)', 2.0) AS RESULT; result ----------- <(0,0),2> (1 row)
- circle(polygon)
Description: Polygon to circle
Return type: circle
For example:
1 2 3 4 5
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
For example:
1 2 3 4 5
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
For example:
1 2 3 4 5
SELECT lseg(point '(-1,0)', point '(1,0)') AS RESULT; result ---------------- [(-1,0),(1,0)] (1 row)
- path(polygon)
Return type: path
For example:
1 2 3 4 5
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)
Return type: point
For example:
1 2 3 4 5
SELECT point(23.4, -44.5) AS RESULT; result -------------- (23.4,-44.5) (1 row)
- point(box)
Return type: point
For example:
1 2 3 4 5
SELECT point(box '((-1,0),(1,0))') AS RESULT; result -------- (0,0) (1 row)
- point(circle)
Return type: point
For example:
1 2 3 4 5
SELECT point(circle '((0,0),2.0)') AS RESULT; result -------- (0,0) (1 row)
- point(lseg)
Description: Center of line segment
Return type: point
For example:
1 2 3 4 5
SELECT point(lseg '((-1,0),(1,0))') AS RESULT; result -------- (0,0) (1 row)
- point(polygon)
Description: Center of polygon
Return type: point
For example:
1 2 3 4 5
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
For example:
1 2 3 4 5
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
For example:
1 2 3 4 5 6
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
For example:
1 2 3 4 5 6
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)
Return type: polygon
For example:
1 2 3 4 5
SELECT polygon(path '((0,0),(1,1),(2,0))') AS RESULT; result --------------------- ((0,0),(1,1),(2,0)) (1 row)