Package org.deegree.crs.transformations.polynomial

A Transformation can be defined as an mathematical operation which transforms some values into other values using a specified function.

See:
Description

Class Summary

LeastSquareApproximation	LeastSquareApproximation is a polynomial transformation which uses the least square method to approximate a function given by some measured values.
PolynomialTransformation	PolynomialTransformation is the base class for all polynomial transformations.

Package org.deegree.crs.transformations.polynomial Description

A Transformation can be defined as an mathematical operation which transforms some values into other values using a specified function. In geographic terms this means, that some incoming coordinate in a specified crs, must be transformed into a coordinate valid for some other crs.

A polynomial transformations use a polynomial to approximate a function which directly transforms coordinates from one crs into another.

Automatic loading of transformation classes

It is possible to create your own transformation classes, which the default provider DeegreeCRSProvider will load automatically.

You can achieve this loading by supplying the class attribute to a crs:CoordinateSystem/crs:transformation element in the 'deegree-crs-configuration.xml'. This attribute must contain the full class name (with package), e.g. <crs:transformation class='my.package.and.transformation.Implementation'>

Because the loading is done with reflections your classes must sustain following criteria:

1. It must be a sub class of PolynomialTransformation
2. A constructor with following signature must be supplied:
   public MyTransformation(
    java.util.list<Double> aValues,
    java.util.list<Double> bValues,
    CoordinateSystem targetCRS,
    java.util.List<org.w3c.dom.Element> yourTransformationElements
);


   The first three parameters are common to all polynomial values (for an explanation of their meaning take a look at PolynomialTransformation). Again, the last list, will contain all xml-dom elements you supplied in the deegree configuration (child elements of the crs:transformation/crs:MyTransformation), thus relieving you of the parsing of the deegree-crs-configuration.xml document.

Version:

$Revision: 10829 $, $Date: 2007-03-20 10:15:15 +0100 (Di, 20 Mrz 2007)$

Author:

Rutger Bezema, last edited by: $Author: rbezema $