| /* |
| * 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.univariate; |
| |
| import org.apache.commons.math3.analysis.UnivariateFunction; |
| import org.apache.commons.math3.optimization.GoalType; |
| import org.junit.Assert; |
| import org.junit.Test; |
| |
| /** |
| * Test for {@link BracketFinder}. |
| */ |
| @Deprecated |
| public class BracketFinderTest { |
| |
| @Test |
| public void testCubicMin() { |
| final BracketFinder bFind = new BracketFinder(); |
| final UnivariateFunction func = new UnivariateFunction() { |
| public double value(double x) { |
| if (x < -2) { |
| return value(-2); |
| } |
| else { |
| return (x - 1) * (x + 2) * (x + 3); |
| } |
| } |
| }; |
| |
| bFind.search(func, GoalType.MINIMIZE, -2 , -1); |
| final double tol = 1e-15; |
| // Comparing with results computed in Python. |
| Assert.assertEquals(-2, bFind.getLo(), tol); |
| Assert.assertEquals(-1, bFind.getMid(), tol); |
| Assert.assertEquals(0.61803399999999997, bFind.getHi(), tol); |
| } |
| |
| @Test |
| public void testCubicMax() { |
| final BracketFinder bFind = new BracketFinder(); |
| final UnivariateFunction func = new UnivariateFunction() { |
| public double value(double x) { |
| if (x < -2) { |
| return value(-2); |
| } |
| else { |
| return -(x - 1) * (x + 2) * (x + 3); |
| } |
| } |
| }; |
| |
| bFind.search(func, GoalType.MAXIMIZE, -2 , -1); |
| final double tol = 1e-15; |
| Assert.assertEquals(-2, bFind.getLo(), tol); |
| Assert.assertEquals(-1, bFind.getMid(), tol); |
| Assert.assertEquals(0.61803399999999997, bFind.getHi(), tol); |
| } |
| |
| @Test |
| public void testMinimumIsOnIntervalBoundary() { |
| final UnivariateFunction func = new UnivariateFunction() { |
| public double value(double x) { |
| return x * x; |
| } |
| }; |
| |
| final BracketFinder bFind = new BracketFinder(); |
| |
| bFind.search(func, GoalType.MINIMIZE, 0, 1); |
| Assert.assertTrue(bFind.getLo() <= 0); |
| Assert.assertTrue(0 <= bFind.getHi()); |
| |
| bFind.search(func, GoalType.MINIMIZE, -1, 0); |
| Assert.assertTrue(bFind.getLo() <= 0); |
| Assert.assertTrue(0 <= bFind.getHi()); |
| } |
| |
| @Test |
| public void testIntervalBoundsOrdering() { |
| final UnivariateFunction func = new UnivariateFunction() { |
| public double value(double x) { |
| return x * x; |
| } |
| }; |
| |
| final BracketFinder bFind = new BracketFinder(); |
| |
| bFind.search(func, GoalType.MINIMIZE, -1, 1); |
| Assert.assertTrue(bFind.getLo() <= 0); |
| Assert.assertTrue(0 <= bFind.getHi()); |
| |
| bFind.search(func, GoalType.MINIMIZE, 1, -1); |
| Assert.assertTrue(bFind.getLo() <= 0); |
| Assert.assertTrue(0 <= bFind.getHi()); |
| |
| bFind.search(func, GoalType.MINIMIZE, 1, 2); |
| Assert.assertTrue(bFind.getLo() <= 0); |
| Assert.assertTrue(0 <= bFind.getHi()); |
| |
| bFind.search(func, GoalType.MINIMIZE, 2, 1); |
| Assert.assertTrue(bFind.getLo() <= 0); |
| Assert.assertTrue(0 <= bFind.getHi()); |
| } |
| } |