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.analysis.UnivariateFunction;
25 import org.hipparchus.analysis.function.Cos;
26 import org.hipparchus.analysis.function.Inverse;
27 import org.hipparchus.analysis.function.Log;
28 import org.junit.jupiter.api.Test;
29
30 import static org.junit.jupiter.api.Assertions.assertEquals;
31
32 /**
33 * Test of the {@link FieldLegendreRuleFactory}.
34 *
35 */
36 class LegendreHighPrecisionTest {
37 private static GaussIntegratorFactory factory = new GaussIntegratorFactory();
38
39 @Test
40 void testCos() {
41 final UnivariateFunction cos = new Cos();
42
43 final GaussIntegrator integrator = factory.legendreHighPrecision(7, 0, Math.PI / 2);
44 final double s = integrator.integrate(cos);
45 // System.out.println("s=" + s + " e=" + 1);
46 assertEquals(1, s, Math.ulp(1d));
47 }
48
49
50 @Test
51 void testInverse() {
52 final UnivariateFunction inv = new Inverse();
53 final UnivariateFunction log = new Log();
54
55 final double lo = 12.34;
56 final double hi = 456.78;
57
58 final GaussIntegrator integrator = factory.legendreHighPrecision(60, lo, hi);
59 final double s = integrator.integrate(inv);
60 final double expected = log.value(hi) - log.value(lo);
61 // System.out.println("s=" + s + " e=" + expected);
62 assertEquals(expected, s, 1e-15);
63 }
64 }