def relate(geom)
      check_geometry(geom)
      FFIGeos.GEOSRelate_r(Geos.current_handle_pointer, ptr, geom.ptr)
    end
def relate(geom)
      check_geometry(geom)
      FFIGeos.GEOSRelate_r(Geos.current_handle_pointer, ptr, geom.ptr)
    end
Returns the Dimensionally Extended Nine-Intersection Model (DE-9IM)
 matrix of the geometries as a String.