...
Most of the geometric functions can be passed either a a string containing Well Known Text String format or a Geometry Object as described below.
Geometric Data Types
Excerpt | ||
---|---|---|
| ||
Well Known TextWell known text (WKT) is a text mark up language for representing vector geometry objects. Most geometric functions accept a string containing well formed WKT syntax. These are known as |
...
WKT strings. For example, "POLYGON ((30 10, 40 40, 20 40, 10 20, 30 10))". WKT is commonly generated and used by Geographic Information Systems (GIS) or geographical databases. For more information on this topic see: Well Known Text GeometryMany geometry functions return a "Geometry" object this is the internal optimised representation of the results which can be passed directly into other geometry functions. Where the final result of an expression is a geometry object then this will automatically be converted into a String once evaluation is complete. To convert a Geometry object into a Well Known Text* string, so that it can be passed to other non-geometry functions toString() must be called. |
Functions
The following function perform geometric operations:
...