1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache License, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 package org.apache.commons.rng.sampling.distribution; 18 19 import org.apache.commons.rng.UniformRandomProvider; 20 21 /** 22 * Sampling from a uniform distribution. 23 */ 24 public class ContinuousUniformSampler 25 extends SamplerBase 26 implements ContinuousSampler { 27 /** Lower bound. */ 28 private final double lo; 29 /** Higher bound. */ 30 private final double hi; 31 /** Underlying source of randomness. */ 32 private final UniformRandomProvider rng; 33 34 /** 35 * @param rng Generator of uniformly distributed random numbers. 36 * @param lo Lower bound. 37 * @param hi Higher bound. 38 */ 39 public ContinuousUniformSampler(UniformRandomProvider rng, 40 double lo, 41 double hi) { 42 super(null); 43 this.rng = rng; 44 this.lo = lo; 45 this.hi = hi; 46 } 47 48 /** {@inheritDoc} */ 49 @Override 50 public double sample() { 51 final double u = rng.nextDouble(); 52 return u * hi + (1 - u) * lo; 53 } 54 55 /** {@inheritDoc} */ 56 @Override 57 public String toString() { 58 return "Uniform deviate [" + rng.toString() + "]"; 59 } 60 }