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Java example source code file (CircleVectorial.java)
The CircleVectorial.java Java example source code/* * 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.fitting.leastsquares; 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; /** * Class used in the tests. */ 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 MultivariateVectorFunction getModelFunction() { return 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 MultivariateMatrixFunction getModelFunctionJacobian() { return 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; } }; } } Other Java examples (source code examples)Here is a short list of links related to this Java CircleVectorial.java source code file: |
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