/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.commons.math3.optim.nonlinear.vector.jacobian;
import java.util.ArrayList;
import org.apache.commons.math3.analysis.MultivariateVectorFunction;
import org.apache.commons.math3.analysis.MultivariateMatrixFunction;
import org.apache.commons.math3.geometry.euclidean.twod.Vector2D;
import org.apache.commons.math3.optim.nonlinear.vector.ModelFunction;
import org.apache.commons.math3.optim.nonlinear.vector.ModelFunctionJacobian;
/**
* Class used in the tests.
*/
@Deprecated
class CircleVectorial {
private ArrayList<Vector2D> points;
public CircleVectorial() {
points = new ArrayList<Vector2D>();
}
public void addPoint(double px, double py) {
points.add(new Vector2D(px, py));
}
public int getN() {
return points.size();
}
public double getRadius(Vector2D center) {
double r = 0;
for (Vector2D point : points) {
r += point.distance(center);
}
return r / points.size();
}
public ModelFunction getModelFunction() {
return new ModelFunction(new MultivariateVectorFunction() {
public double[] value(double[] params) {
Vector2D center = new Vector2D(params[0], params[1]);
double radius = getRadius(center);
double[] residuals = new double[points.size()];
for (int i = 0; i < residuals.length; i++) {
residuals[i] = points.get(i).distance(center) - radius;
}
return residuals;
}
});
}
public ModelFunctionJacobian getModelFunctionJacobian() {
return new ModelFunctionJacobian(new MultivariateMatrixFunction() {
public double[][] value(double[] params) {
final int n = points.size();
final Vector2D center = new Vector2D(params[0], params[1]);
double dRdX = 0;
double dRdY = 0;
for (Vector2D pk : points) {
double dk = pk.distance(center);
dRdX += (center.getX() - pk.getX()) / dk;
dRdY += (center.getY() - pk.getY()) / dk;
}
dRdX /= n;
dRdY /= n;
// Jacobian of the radius residuals.
double[][] jacobian = new double[n][2];
for (int i = 0; i < n; i++) {
final Vector2D pi = points.get(i);
final double di = pi.distance(center);
jacobian[i][0] = (center.getX() - pi.getX()) / di - dRdX;
jacobian[i][1] = (center.getY() - pi.getY()) / di - dRdY;
}
return jacobian;
}
});
}
}