The Well-Known Text (WKT) representation of Geometry is designed to exchange geometry data in ASCII form.
Examples of WKT representations of geometry objects:
            A Point:
          
POINT(15 20)
Note that point coordinates are specified with no separating comma.
            A LineString with four points:
          
LINESTRING(0 0, 10 10, 20 25, 50 60)
Note that point coordinate pairs are separated by commas.
            A Polygon with one exterior ring and one
            interior ring:
          
POLYGON((0 0,10 0,10 10,0 10,0 0),(5 5,7 5,7 7,5 7, 5 5))
            A MultiPoint with three
            Point values:
          
MULTIPOINT(0 0, 20 20, 60 60)
            A MultiLineString with two
            LineString values:
          
MULTILINESTRING((10 10, 20 20), (15 15, 30 15))
            A MultiPolygon with two
            Polygon values:
          
MULTIPOLYGON(((0 0,10 0,10 10,0 10,0 0)),((5 5,7 5,7 7,5 7, 5 5)))
            A GeometryCollection consisting of two
            Point values and one
            LineString:
          
GEOMETRYCOLLECTION(POINT(10 10), POINT(30 30), LINESTRING(15 15, 20 20))
A Backus-Naur grammar that specifies the formal production rules for writing WKT values can be found in the OpenGIS specification document referenced near the beginning of this chapter.


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