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Java > Open Source Codes > org > apache > commons > math > analysis > UnivariateRealSolverFactory


1 /*
2  * Copyright 2003-2004 The Apache Software Foundation.
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 org.apache.commons.math.analysis;
17
18 import org.apache.commons.discovery.tools.DiscoverClass;
19
20 /**
21  * Abstract factory class used to create {@link UnivariateRealSolver} instances.
22  * <p>
23  * Solvers implementing the following algorithms are supported:
24  * <ul>
25  * <li>Bisection</li>
26  * <li>Brent's method</li>
27  * <li>Secant method</li>
28  * </ul>
29  * Concrete factories extending this class also specify a default solver, instances of which
30  * are returned by <code>newDefaultSolver()</code>.
31  * <p>
32  * Common usage:<pre>
33  * SolverFactory factory = UnivariateRealSolverFactory.newInstance();
34  *
35  * // create a Brent solver to use with a UnivariateRealFunction f
36  * BrentSolver solver = factory.newBrentSolver(f);
37  * </pre>
38  *
39  * <a HREF="http://jakarta.apache.org/commons/discovery/">Jakarta Commons Discovery</a>
40  * is used to determine the concrete factory returned by
41  * <code>UnivariateRealSolverFactory.newInstance().</code> The default is
42  * {@link UnivariateRealSolverFactoryImpl}.
43  *
44  * @version $Revision$ $Date: 2005-02-26 05:11:52 -0800 (Sat, 26 Feb 2005) $
45  */
46 public abstract class UnivariateRealSolverFactory {
47     /**
48      * Default constructor.
49      */
50     protected UnivariateRealSolverFactory() {
51     }
52
53     /**
54      * Create a new factory.
55      * @return a new factory.
56      */
57     public static UnivariateRealSolverFactory newInstance() {
58         UnivariateRealSolverFactory factory = null;
59         try {
60             DiscoverClass dc = new DiscoverClass();
61             factory = (UnivariateRealSolverFactory) dc.newInstance(
62                 UnivariateRealSolverFactory.class,
63                 "org.apache.commons.math.analysis.UnivariateRealSolverFactoryImpl");
64         } catch(Throwable JavaDoc t) {
65             return new UnivariateRealSolverFactoryImpl();
66         }
67         return factory;
68     }
69     
70     /**
71      * Create a new {@link UnivariateRealSolver} for the given function. The
72      * actual solver returned is determined by the underlying factory.
73      * @param f the function.
74      * @return the new solver.
75      */
76     public abstract UnivariateRealSolver newDefaultSolver(
77         UnivariateRealFunction f);
78     
79     /**
80      * Create a new {@link UnivariateRealSolver} for the given function. The
81      * solver is an implementation of the bisection method.
82      * @param f the function.
83      * @return the new solver.
84      */
85     public abstract UnivariateRealSolver newBisectionSolver(
86         UnivariateRealFunction f);
87     
88     /**
89      * Create a new {@link UnivariateRealSolver} for the given function. The
90      * solver is an implementation of the Brent method.
91      * @param f the function.
92      * @return the new solver.
93      */
94     public abstract UnivariateRealSolver newBrentSolver(
95         UnivariateRealFunction f);
96     
97     /**
98      * Create a new {@link UnivariateRealSolver} for the given function. The
99      * solver is an implementation of Newton's Method.
100      * @param f the function.
101      * @return the new solver.
102      */
103     public abstract UnivariateRealSolver newNewtonSolver(
104         DifferentiableUnivariateRealFunction f);
105     
106     /**
107      * Create a new {@link UnivariateRealSolver} for the given function. The
108      * solver is an implementation of the secant method.
109      * @param f the function.
110      * @return the new solver.
111      */
112     public abstract UnivariateRealSolver newSecantSolver(
113         UnivariateRealFunction f);
114 }
115
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