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 /** 20 * Sampling from a Gaussian distribution with given mean and 21 * standard deviation. 22 * 23 * @since 1.1 24 */ 25 public class GaussianSampler implements ContinuousSampler { 26 /** Mean. */ 27 private final double mean; 28 /** standardDeviation. */ 29 private final double standardDeviation; 30 /** Normalized Gaussian sampler. */ 31 private final NormalizedGaussianSampler normalized; 32 33 /** 34 * @param normalized Generator of N(0,1) Gaussian distributed random numbers. 35 * @param mean Mean of the Gaussian distribution. 36 * @param standardDeviation Standard deviation of the Gaussian distribution. 37 */ 38 public GaussianSampler(NormalizedGaussianSampler normalized, 39 double mean, 40 double standardDeviation) { 41 this.normalized = normalized; 42 this.mean = mean; 43 this.standardDeviation = standardDeviation; 44 } 45 46 /** {@inheritDoc} */ 47 @Override 48 public double sample() { 49 return standardDeviation * normalized.sample() + mean; 50 } 51 52 /** {@inheritDoc} */ 53 @Override 54 public String toString() { 55 return "Gaussian deviate [" + normalized.toString() + "]"; 56 } 57 }