MinkowskiDistance Class Reference

Inheritance diagram for MinkowskiDistance:

Collaboration diagram for MinkowskiDistance:

Public Member Functions
String	getURI ()
Value	evaluate (ValueFactory valueFactory, Value... args) throws ValueExprEvaluationException

Protected Member Functions
double	relation (Geometry geom1, Geometry geom2, Double power)

Member Function Documentation

evaluate()

Value evaluate ( ValueFactory  valueFactory, Value...  args  ) throws ValueExprEvaluationException

inherited

                                                                                                            {
                if (args.length != 3) {
                        throw new ValueExprEvaluationException(getURI() + " requires exactly 3 arguments, got " + args.length);
                }
 
                LiteralType l=LiteralRegistry.getLiteral(((Literal)args[0]).getDatatype().toString());
                LiteralType l2=LiteralRegistry.getLiteral(((Literal)args[1]).getDatatype().toString());
                Double value=Double.valueOf(args[2].stringValue());
                if(l instanceof VectorLiteral && l2 instanceof VectorLiteral) {
                        Geometry geom=((VectorLiteral)l).read(args[0].stringValue());
                        Geometry geom2=((VectorLiteral)l2).read(args[1].stringValue());
                        Geometry transformed=LiteralUtils.transform(geom2, geom);
                        double result = relation(geom,transformed,value);
                        return valueFactory.createLiteral(result);
                }
                throw new ValueExprEvaluationException("Arguments given are not a geometry literal");
 
        }

References LiteralRegistry.getLiteral(), GeometricRelationDoubleDoubleFunction.relation(), and LiteralUtils.transform().

getURI()

String getURI

(

)

                               {
                return POSTGIS.st_minkowskidistance.stringValue();
        }

References POSTGIS.st_minkowskidistance.

relation()

double relation ( Geometry  geom1, Geometry  geom2, Double  power  )

protected

Reimplemented from GeometricRelationDoubleDoubleFunction.

                                                                               {
                double sum=0.;
                for(Coordinate coord:geom1.getCoordinates()) {
                        sum+=Math.pow(Math.abs(coord.y-coord.x), power);
                }
                return Math.pow(sum, 1 / power);    
        }