The gml:coverageFunction property describes the mapping function from thedomain to the range of the coverage. The value of the CoverageFunction is one ofgml:CoverageMappingRule and gml:GridFunction. If the gml:coverageFunction property isomitted for a gridded coverage (including rectified gridded coverages) the gml:startPoint isassumed to be the value of the gml:low property in the gml:Grid geometry, and thegml:sequenceRule is assumed to be linear and the gml:axisOrder property is assumed to be“+1 +2â€.