Polygon and spatial match, bug ?

_olivierbisthoven

Hi Community,

As nobody have found explanations to the following problems, I reintroduce it with a bug label

I try to match the content of two shapefiles using the predicate Target Within Univers and I observe unexpected behavior.

The two files in the samples contains one polygon each. obj1.shp is included in obj2.shp : A quick check with Brower tool show that is correct.

Nevertheless using Spatial Match on this very simple example fails !

On the other side using Custom DE-9IM spec coding "within" i.e.  T*F**F*** the result is correct !

Could anyone explains this strange result

MAtchingPuzzle.zip

GiuseppeC

Hi @_olivierbisthoven,

the only explanation is that the 'small' polygon defined in obj1.shp contains something else that is not visible on the map.

If you see my attachment, I used the Summarize tool to Combine the 2 polygons. Then used the SpatialInfo tool to get the areas and compared obj2's area to the area of the 'combined' polygon (i.e. obj1+obj2). They are different in size (obj2: 8.63762439090817e-04 vs combined: 8.64073468040519e-04 SqKm) and the fact that the matching with the "within" setting is not happening, tells me that obj1 contains something that's outside of obj2.

The SpatialMatch would find a match if you switched the setting to 'intersects'.

Hope this helps!

Giuseppe

MAtchingPuzzlev2.yxmd