I have a shapefile containing polygons and a shapefile containing points. Now I would like to select the polygons that contain points.
How can I do this from the command line using ogr2ogr
?
Answer
At the following link all SQL functions that test spatial relationships are described: http://www.gaia-gis.it/spatialite-2.4.0/spatialite-sql-2.4.html#p12.
The following spatial relationships can be used within a query
ST_Equals
- ST_Disjoint
- ST_Touches
- ST_Within
- ST_Overlaps
- ST_Crosses
- ST_Intersects
- ST_Contains
- ST_Relate
For this type of request you can do this using the ST_Containts
query of sqlite
. Which can be adopted in a ogr2ogr
command as follows:
ogr2ogr -f "ESRI Shapefile" selection_polygon.shp shapefile_polygon.shp -dialect sqlite -sql "SELECT polygon.Geometry, polygon.id FROM shapefile_polygon polygon, 'shapefile_point.shp'.shapefile_point point WHERE ST_Contains(polygon.geometry, point.geometry) GROUP BY polygon.id"
Example
Picture of shapefile_polygon.shp
and shapefile_point.shp
: And picture of selection_polygon.shp
and shapefile_point.shp
:
Expanded options of the spatial relationships:
ST_Equals
Returns true if the interior and the boundary of the two geometries are spatially equalST_Disjoint
Returns true if the boundaries and interior do not intersectST_Touches
Returns true if the boundaries intersect but the interiors do notST_Within
Returns true if the interior of the given geometry does not intersect with the exterior of another geometryST_Overlaps
Returns true if the interiors of two geometries have non-empty intersectionST_Crosses
Returns true if the interiors of the geometries intersect but the boundaries do notST_Intersects
Returns true if the interiors of the geometries intersectST_Contains
Tests if the given geometry contains another geometryST_Relate
Returns true if this geometry is spatially related to another geometry
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