1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * https://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17
18 /*
19 * This is not the original file distributed by the Apache Software Foundation
20 * It has been modified by the Hipparchus project
21 */
22 package org.hipparchus.analysis.integration.gauss;
23
24 import org.hipparchus.util.FastMath;
25 import org.junit.jupiter.params.ParameterizedTest;
26 import org.junit.jupiter.params.provider.MethodSource;
27
28 import java.util.ArrayList;
29 import java.util.Collection;
30
31 /**
32 * Test of the {@link HermiteRuleFactory}.
33 * This parameterized test extends the standard test for Gaussian quadrature
34 * rule, where each monomial is tested in turn.
35 * Parametrization allows to test automatically 0, 1, ... , {@link #MAX_NUM_POINTS}
36 * quadrature rules.
37 *
38 */
39 public class HermiteParametricTest extends GaussianQuadratureAbstractTest {
40 private static final double SQRT_PI = FastMath.sqrt(Math.PI);
41 private static final GaussIntegratorFactory factory = new GaussIntegratorFactory();
42
43 /**
44 * The highest order quadrature rule to be tested.
45 */
46 public static final int MAX_NUM_POINTS = 30;
47
48 /**
49 * Returns the collection of parameters to be passed to the constructor of
50 * this class.
51 * Gauss-Hermite quadrature rules of order 1, ..., {@link #MAX_NUM_POINTS}
52 * will be constructed.
53 *
54 * @return the collection of parameters for this parameterized test.
55 */
56 public static Collection<Object[]> getParameters() {
57 final ArrayList<Object[]> parameters = new ArrayList<Object[]>();
58 final int [] numUlps = {
59 10, 10, 10, 10, 20,
60 20, 20, 20, 30, 40,
61 40, 50, 150, 150, 150,
62 150, 150, 150, 150, 200,
63 250, 250, 300, 300, 300,
64 300, 300, 300, 350, 350
65 };
66 for (int k = 1; k <= MAX_NUM_POINTS; k++) {
67 parameters.add(new Object[] { k, 2 * k - 1, FastMath.ulp(1d), numUlps[k - 1] });
68 }
69 return parameters;
70 }
71
72 @Override
73 public double getExpectedValue(final int n) {
74 if (n % 2 == 1) {
75 return 0;
76 }
77
78 final int iMax = n / 2;
79 double p = 1;
80 double q = 1;
81 for (int i = 0; i < iMax; i++) {
82 p *= 2 * i + 1;
83 q *= 2;
84 }
85
86 return p / q * SQRT_PI;
87 }
88
89 @ParameterizedTest
90 @MethodSource("getParameters")
91 void testAllMonomials(int numberOfPoints, int maxDegree, double eps,
92 double numUlps) {
93 super.testAllMonomials(factory.hermite(numberOfPoints), maxDegree, eps,
94 numUlps);
95 }
96 }