Coverage Report - org.apache.commons.math.distribution.IntegerDistribution

Classes in this File	Line Coverage	Branch Coverage	Complexity
IntegerDistribution	N/A	N/A	1.0;1

1		/*
2		* Copyright 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		import org.apache.commons.math.MathException;
19
20		/**
21		* Interface for discrete distributions of integer-valued random variables.
22		*
23		* @version $Revision$ $Date: 2005-02-26 05:11:52 -0800 (Sat, 26 Feb 2005) $
24		*/
25		public interface IntegerDistribution extends DiscreteDistribution {
26		/**
27		* For a random variable X whose values are distributed according
28		* to this distribution, this method returns P(X = x). In other words, this
29		* method represents the probability mass function for the distribution.
30		*
31		* @param x the value at which the probability density function is evaluated.
32		* @return the value of the probability density function at x
33		*/
34		double probability(int x);
35
36		/**
37		* For a random variable X whose values are distributed according
38		* to this distribution, this method returns P(X ≤ x). In other words,
39		* this method represents the probability distribution function, or PDF
40		* for the distribution.
41		*
42		* @param x the value at which the PDF is evaluated.
43		* @return PDF for this distribution.
44		* @throws MathException if the cumulative probability can not be
45		* computed due to convergence or other numerical errors.
46		*/
47		double cumulativeProbability(int x) throws MathException;
48
49		/**
50		* For this distribution, X, this method returns P(x0 ≤ X ≤ x1).
51		* @param x0 the inclusive, lower bound
52		* @param x1 the inclusive, upper bound
53		* @return the cumulative probability.
54		* @throws MathException if the cumulative probability can not be
55		* computed due to convergence or other numerical errors.
56		* @throws IllegalArgumentException if x0 > x1
57		*/
58		double cumulativeProbability(int x0, int x1) throws MathException;
59
60		/**
61		* For this distribution, X, this method returns the largest x such that
62		* P(X &le; x) <= p.
63		* <p>
64		* Note that this definition implies: <ul>
65		* <li> If there is a minimum value, <code>m</code>, with postive
66		* probablility under (the density of) X, then <code>m - 1</code> is
67		* returned by <code>inverseCumulativeProbability(0).</code> If there is
68		* no such value <code>m, Integer.MIN_VALUE</code> is
69		* returned.</li>
70		* <li> If there is a maximum value, <code>M</code>, such that
71		* P(X &le; M) =1, then <code>M</code> is returned by
72		* <code>inverseCumulativeProbability(1).</code>
73		* If there is no such value, <code>M, Integer.MAX_VALUE</code> is
74		* returned.</li></ul>
75		*
76		* @param p the cumulative probability.
77		* @return the largest x such that P(X &le; x) <= p
78		* @throws MathException if the inverse cumulative probability can not be
79		* computed due to convergence or other numerical errors.
80		* @throws IllegalArgumentException if p is not between 0 and 1 (inclusive)
81		*/
82		int inverseCumulativeProbability(double p) throws MathException;
83		}