1 /*
2 * Copyright (C) 2023 Alberto Irurueta Carro (alberto@irurueta.com)
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16 package com.irurueta.numerical.integration;
17
18 import com.irurueta.numerical.SingleDimensionFunctionEvaluatorListener;
19
20 /**
21 * Computes function integration by using Simpson's rule and infinity mid-point quadrature.
22 * This type of integrator will in general be more efficient than Trapezoidal quadrature
23 * integrators (i.e., require fewer function evaluations) when the function
24 * to be integrated has a finite fourth derivative (i.e., a continuous third derivative).
25 * If you need to integrate from a negative lower limit to positive infinity, you do this by
26 * breaking the integral into two pieces at some positive value:
27 * SimpsonInfinityMidPointQuadratureIntegrator integrator1 =
28 * new SimpsonInfinityMidPointQuadratureIntegrator(-5.0, 2.0, listener);
29 * SimpsonInfinityMidPointQuadratureIntegrator integrator2 =
30 * new SimpsonInfinityMidPointQuadratureIntegrator(2.0, 1e99, listener);
31 * double integral = integrator1.integrate() + integrator2.integrate();
32 */
33 public class SimpsonInfinityMidPointQuadratureIntegrator extends SimpsonIntegrator<InfinityMidPointQuadrature> {
34
35 /**
36 * Constructor.
37 *
38 * @param a Lower limit of integration.
39 * @param b Upper limit of integration.
40 * @param listener listener to evaluate a single dimension function at required points.
41 * @param eps required accuracy.
42 */
43 public SimpsonInfinityMidPointQuadratureIntegrator(
44 final double a, final double b, final SingleDimensionFunctionEvaluatorListener listener, final double eps) {
45 super(new InfinityMidPointQuadrature(a, b, listener), eps);
46 }
47
48 /**
49 * Constructor.
50 *
51 * @param a Lower limit of integration.
52 * @param b Upper limit of integration.
53 * @param listener listener to evaluate a single dimension function at required points.
54 */
55 public SimpsonInfinityMidPointQuadratureIntegrator(
56 final double a, final double b, final SingleDimensionFunctionEvaluatorListener listener) {
57 this(a, b, listener, EPS);
58 }
59
60 /**
61 * Gets type of quadrature.
62 *
63 * @return type of quadrature.
64 */
65 @Override
66 public QuadratureType getQuadratureType() {
67 return QuadratureType.INFINITY_MID_POINT;
68 }
69 }