| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.commons.rng.sampling.distribution; |
| |
| /** |
| * Interface for a discrete distribution that can be sampled using |
| * the <a href="https://en.wikipedia.org/wiki/Inverse_transform_sampling"> |
| * inversion method</a>. |
| * |
| * @since 1.0 |
| */ |
| public interface DiscreteInverseCumulativeProbabilityFunction { |
| /** |
| * Computes the quantile function of the distribution. |
| * For a random variable {@code X} distributed according to this distribution, |
| * the returned value is |
| * <ul> |
| * <li>\( \inf_{x \in \mathcal{Z}} P(X \le x) \ge p \) for \( 0 \lt p \le 1 \)</li> |
| * <li>\( \inf_{x \in \mathcal{Z}} P(X \le x) \gt 0 \) for \( p = 0 \)</li> |
| * </ul> |
| * |
| * @param p Cumulative probability. |
| * @return the smallest {@code p}-quantile of the distribution |
| * (largest 0-quantile for {@code p = 0}). |
| * @throws IllegalArgumentException if {@code p < 0} or {@code p > 1}. |
| */ |
| int inverseCumulativeProbability(double p); |
| } |