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Updated on 2024-08-20 GMT+08:00
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Geometric Functions and Operators

Geometric Operators

  • +

    Description: Translation

    Example:

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    gaussdb=# SELECT box '((0,0),(1,1))' + point '(2.0,0)' AS RESULT;
   result    
-------------
 (3,1),(2,0)
(1 row)
  • -

    Description: Translation

    Example:

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    gaussdb=# SELECT box '((0,0),(1,1))' - point '(2.0,0)' AS RESULT;
    result     
---------------
 (-1,1),(-2,0)
(1 row)
  • *

    Description: Scaling out/Rotation

    Example:

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    gaussdb=# SELECT box '((0,0),(1,1))' * point '(2.0,0)' AS RESULT;
   result    
-------------
 (2,2),(0,0)
(1 row)
  • /

    Description: Scaling in/Rotation

    Example:

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    gaussdb=# 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:

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    gaussdb=# 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

    Example:

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    gaussdb=# SELECT # path'((1,0),(0,1),(-1,0))' AS RESULT;
 result 
--------
      3
(1 row)
  • @-@

    Description: Length or circumference

    Example:

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    gaussdb=# SELECT @-@ path '((0,0),(1,0))' AS RESULT;
 result 
--------
      2
(1 row)
  • @@

    Description: Center of box

    Example:

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    gaussdb=# SELECT @@ circle '((0,0),10)' AS RESULT;
 result 
--------
 (0,0)
(1 row)
  • <->

    Description: Distance between the two figures

    Example:

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    gaussdb=# 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:

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    gaussdb=# 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:

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    gaussdb=# 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:

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    gaussdb=# SELECT circle '((5,0),1)' >> circle '((0,0),1)' AS RESULT;
 result 
--------
 t
(1 row)
  • &<

    Description: Does not extend to the right of?

    Example:

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    gaussdb=# 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:

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    gaussdb=# 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:

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    gaussdb=# 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:

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    gaussdb=# SELECT box '((3,4),(5,5))' |>> box '((0,0),(3,3))' AS RESULT;
 result 
--------
 t
(1 row)
  • &<|

    Description: Does not extend above?

    Example:

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    gaussdb=# SELECT box '((0,0),(1,1))' &<| box '((0,0),(2,2))' AS RESULT;
 result 
--------
 t
(1 row)
  • |&>

    Description: Does not extend below?

    Example:

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    gaussdb=# SELECT box '((0,0),(3,3))' |&> box '((0,0),(2,2))' AS RESULT;
 result 
--------
 t
(1 row)
  • <^

    Description: Is below (allows touching)?

    Example:

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    gaussdb=# SELECT box '((0,0),(-3,-3))' <^ box '((0,0),(2,2))' AS RESULT;
 result 
--------
 t
(1 row)
  • >^

    Description: Is above (allows touching)?

    Example:

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    gaussdb=# SELECT box '((0,0),(2,2))' >^ box '((0,0),(-3,-3))'  AS RESULT;
 result 
--------
 t
(1 row)
  • ?#

    Description: Intersect?

    Example:

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    gaussdb=# SELECT lseg '((-1,0),(1,0))' ?# box '((-2,-2),(2,2))' AS RESULT;
 result 
--------
 t
(1 row)
  • ?-

    Description: Is horizontal?

    Example:

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    gaussdb=# SELECT ?- lseg '((-1,0),(1,0))' AS RESULT;
 result 
--------
 t
(1 row)
  • ?-

    Description: Are horizontally aligned?

    Example:

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    gaussdb=# SELECT point '(1,0)' ?- point '(0,0)' AS RESULT;
 result 
--------
 t
(1 row)
  • ?|

    Description: Is vertical?

    Example:

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    gaussdb=# SELECT ?| lseg '((-1,0),(1,0))' AS RESULT;
 result 
--------
 f
(1 row)
  • ?|

    Description: Are vertically aligned?

    Example:

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    gaussdb=# SELECT point '(0,1)' ?| point '(0,0)' AS RESULT;
 result 
--------
 t
(1 row)
  • ?-|

    Description: Are perpendicular?

    Example:

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    gaussdb=# SELECT lseg '((0,0),(0,1))' ?-| lseg '((0,0),(1,0))' AS RESULT;
 result 
--------
 t
(1 row)
  • ?||

    Description: Are parallel?

    Example:

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    gaussdb=# SELECT lseg '((-1,0),(1,0))' ?|| lseg '((-1,2),(1,2))' AS RESULT;
 result 
--------
 t
(1 row)
  • @>

    Description: Contains?

    Example:

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    gaussdb=# SELECT circle '((0,0),2)' @> point '(1,1)' AS RESULT;
 result 
--------
 t
(1 row)
  • <@

    Description: Contained in or on?

    Example:

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    gaussdb=# SELECT point '(1,1)' <@ circle '((0,0),2)' AS RESULT;
 result 
--------
 t
(1 row)
  • ~=

    Description: Specifies whether two figures are the same.

    Example:

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    gaussdb=# 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:

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    gaussdb=# SELECT area(box '((0,0),(1,1))') AS RESULT;
 result 
--------
      1
(1 row)
  • center(object)

    Description: Figure center calculation

    Return type: point

    Example:

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    gaussdb=# 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:

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    gaussdb=# 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:

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    gaussdb=# SELECT height(box '((0,0),(1,1))') AS RESULT;
 result 
--------
      1
(1 row)
  • isclosed(path)

    Description: A closed path?

    Return type: Boolean

    Example:

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    gaussdb=# 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:

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    gaussdb=# 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:

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    gaussdb=# SELECT length(path '((-1,0),(1,0))') AS RESULT;
 result 
--------
      4
(1 row)
  • npoints(path)

    Description: Number of points in path

    Return type: int

    Example:

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    gaussdb=# 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

    Example:

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    gaussdb=# SELECT npoints(polygon '((1,1),(0,0))') AS RESULT;
 result 
--------
      2
(1 row)
  • pclose(path)

    Description: Converts path to closed.

    Return type: path

    Example:

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    gaussdb=# 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

    Example:

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    gaussdb=# 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

    Example:

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    gaussdb=# SELECT radius(circle '((0,0),2.0)') AS RESULT;
 result 
--------
      2
(1 row)
  • width(box)

    Description: Horizontal size of box

    Return type: double precision

    Example:

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    gaussdb=# 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:

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    gaussdb=# 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:

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    gaussdb=# 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:

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    gaussdb=# 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:

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    gaussdb=# 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:

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    gaussdb=# 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:

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    gaussdb=# 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:

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    gaussdb=# 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:

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    gaussdb=# 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:

    gaussdb=# SELECT slope(point '(1,1)', point '(0,0)') AS RESULT;
 result
--------
      1
(1 row)
  • path(polygon)

    Description: Polygon to path

    Return type: path

    Example:

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    gaussdb=# 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:

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    gaussdb=# SELECT point(23.4, -44.5) AS RESULT;
    result    
--------------
 (23.4,-44.5)
(1 row)
  • point(box)

    Description: Center of box

    Return type: point

    Example:

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    gaussdb=# SELECT point(box '((-1,0),(1,0))') AS RESULT;
 result 
--------
 (0,0)
(1 row)
  • point(circle)

    Description: Center of circle

    Return type: point

    Example:

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    gaussdb=# 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:

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    gaussdb=# 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:

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    gaussdb=# 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:

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    gaussdb=# 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:

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    gaussdb=# 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:

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    gaussdb=# 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:

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    gaussdb=# SELECT polygon(path '((0,0),(1,1),(2,0))') AS RESULT;
       result        
---------------------
 ((0,0),(1,1),(2,0))
(1 row)
Parent topic: Functions and Operators