| /* |
| * 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.optimization.general; |
| |
| import java.util.ArrayList; |
| |
| import org.apache.commons.math3.analysis.differentiation.DerivativeStructure; |
| import org.apache.commons.math3.analysis.differentiation.MultivariateDifferentiableFunction; |
| import org.apache.commons.math3.geometry.euclidean.twod.Vector2D; |
| |
| /** |
| * Class used in the tests. |
| */ |
| @Deprecated |
| public class CircleScalar implements MultivariateDifferentiableFunction { |
| private ArrayList<Vector2D> points; |
| |
| public CircleScalar() { |
| points = new ArrayList<Vector2D>(); |
| } |
| |
| public void addPoint(double px, double py) { |
| points.add(new Vector2D(px, py)); |
| } |
| |
| public double getRadius(Vector2D center) { |
| double r = 0; |
| for (Vector2D point : points) { |
| r += point.distance(center); |
| } |
| return r / points.size(); |
| } |
| |
| private DerivativeStructure distance(Vector2D point, |
| DerivativeStructure cx, DerivativeStructure cy) { |
| DerivativeStructure dx = cx.subtract(point.getX()); |
| DerivativeStructure dy = cy.subtract(point.getY()); |
| return dx.multiply(dx).add(dy.multiply(dy)).sqrt(); |
| } |
| |
| public DerivativeStructure getRadius(DerivativeStructure cx, DerivativeStructure cy) { |
| DerivativeStructure r = cx.getField().getZero(); |
| for (Vector2D point : points) { |
| r = r.add(distance(point, cx, cy)); |
| } |
| return r.divide(points.size()); |
| } |
| |
| public double value(double[] variables) { |
| Vector2D center = new Vector2D(variables[0], variables[1]); |
| double radius = getRadius(center); |
| |
| double sum = 0; |
| for (Vector2D point : points) { |
| double di = point.distance(center) - radius; |
| sum += di * di; |
| } |
| |
| return sum; |
| } |
| |
| public DerivativeStructure value(DerivativeStructure[] variables) { |
| DerivativeStructure radius = getRadius(variables[0], variables[1]); |
| |
| DerivativeStructure sum = variables[0].getField().getZero(); |
| for (Vector2D point : points) { |
| DerivativeStructure di = distance(point, variables[0], variables[1]).subtract(radius); |
| sum = sum.add(di.multiply(di)); |
| } |
| |
| return sum; |
| } |
| |
| } |