001    /*
002     * Licensed to the Apache Software Foundation (ASF) under one or more
003     * contributor license agreements.  See the NOTICE file distributed with
004     * this work for additional information regarding copyright ownership.
005     * The ASF licenses this file to You under the Apache License, Version 2.0
006     * (the "License"); you may not use this file except in compliance with
007     * the License.  You may obtain a copy of the License at
008     *
009     *      http://www.apache.org/licenses/LICENSE-2.0
010     *
011     * Unless required by applicable law or agreed to in writing, software
012     * distributed under the License is distributed on an "AS IS" BASIS,
013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014     * See the License for the specific language governing permissions and
015     * limitations under the License.
016     */
017    package org.apache.commons.math.distribution;
018    
019    /**
020     * Student's t-Distribution.
021     *
022     * <p>
023     * References:
024     * <ul>
025     * <li><a href="http://mathworld.wolfram.com/Studentst-Distribution.html">
026     * Student's t-Distribution</a></li>
027     * </ul>
028     * </p>
029     *
030     * @version $Id: TDistribution.java 1131229 2011-06-03 20:49:25Z luc $
031     */
032    public interface TDistribution extends ContinuousDistribution {
033        /**
034         * Access the number of degrees of freedom.
035         *
036         * @return the degrees of freedom.
037         */
038        double getDegreesOfFreedom();
039    }