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.distribution;
17
18 /**
19 * The Chi-Squared Distribution.
20 *
21 * Instances of ChiSquaredDistribution objects should be created using
22 * {@link DistributionFactory#createChiSquareDistribution(double)}.
23 *
24 * <p>
25 * References:
26 * <ul>
27 * <li><a href="http://mathworld.wolfram.com/Chi-SquaredDistribution.html">
28 * Chi-Squared Distribution</a></li>
29 * </ul>
30 * </p>
31 *
32 * @version $Revision: 155427 $ $Date: 2005-02-26 06:11:52 -0700 (Sat, 26 Feb 2005) $
33 */
34 public interface ChiSquaredDistribution extends ContinuousDistribution {
35 /**
36 * Modify the degrees of freedom.
37 * @param degreesOfFreedom the new degrees of freedom.
38 */
39 void setDegreesOfFreedom(double degreesOfFreedom);
40
41 /**
42 * Access the degrees of freedom.
43 * @return the degrees of freedom.
44 */
45 double getDegreesOfFreedom();
46 }