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Is there a way to find the DE-9IM matrix using a spatialite function?

I realize that one can use relate() function to determine if two geometries match a matrix, but I would like to get the matrix instead.

I find it useful to examine DE-9IM matrices when trying to determining whether there are slivers or the like in a JOIN ON INTERSECTS();

http://en.wikipedia.org/wiki/DE-9IM

http://postgis.net/docs/manual-1.4/ST_Relate.html

forkandwait
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1 Answers1

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Spatialite also has ST_Relate implemented. Both Spatialite and Postgis expose this from the GEOS library. For Spatialite see: http://www.gaia-gis.it/gaia-sins/spatialite-sql-4.2.0.html :

"ST_Relate( geom1 Geometry , geom2 Geometry , patternMatrix String ) : Integer returns TRUE if the spatial relationship specified by the patternMatrix holds"

Where "patternMatrix" is meant the same as "intersectionMatrixPattern" in the Postgis docs.

klas2iop
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