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 18 package org.apache.commons.math.estimation; 19 20 import java.io.Serializable; 21 22 /** 23 * This class represents measurements in estimation problems. 24 * 25 * <p>This abstract class implements all the methods needed to handle 26 * measurements in a general way. It defines neither the {@link 27 * #getTheoreticalValue getTheoreticalValue} nor the {@link 28 * #getPartial getPartial} methods, which should be defined by 29 * sub-classes according to the specific problem.</p> 30 * 31 * <p>The {@link #getTheoreticalValue getTheoreticalValue} and {@link 32 * #getPartial getPartial} methods must always use the current 33 * estimate of the parameters set by the solver in the problem. These 34 * parameters can be retrieved through the {@link 35 * EstimationProblem#getAllParameters 36 * EstimationProblem.getAllParameters} method if the measurements are 37 * independent of the problem, or directly if they are implemented as 38 * inner classes of the problem.</p> 39 * 40 * <p>The instances for which the <code>ignored</code> flag is set 41 * through the {@link #setIgnored setIgnored} method are ignored by the 42 * solvers. This can be used to reject wrong measurements at some 43 * steps of the estimation.</p> 44 * 45 * @see EstimationProblem 46 * 47 * @version $Revision: 811827 $ $Date: 2009-09-06 17:32:50 +0200 (dim. 06 sept. 2009) $ 48 * @since 1.2 49 * @deprecated as of 2.0, everything in package org.apache.commons.math.estimation has 50 * been deprecated and replaced by package org.apache.commons.math.optimization.general 51 */ 52 53 @Deprecated 54 public abstract class WeightedMeasurement implements Serializable { 55 56 /** Serializable version identifier. */ 57 private static final long serialVersionUID = 4360046376796901941L; 58 59 /** Measurement weight. */ 60 private final double weight; 61 62 /** Value of the measurements. */ 63 private final double measuredValue; 64 65 /** Ignore measurement indicator. */ 66 private boolean ignored; 67 68 /** 69 * Simple constructor. 70 * Build a measurement with the given parameters, and set its ignore 71 * flag to false. 72 * @param weight weight of the measurement in the least squares problem 73 * (two common choices are either to use 1.0 for all measurements, or to 74 * use a value proportional to the inverse of the variance of the measurement 75 * type) 76 * 77 * @param measuredValue measured value 78 */ 79 public WeightedMeasurement(double weight, double measuredValue) { 80 this.weight = weight; 81 this.measuredValue = measuredValue; 82 ignored = false; 83 } 84 85 /** Simple constructor. 86 * 87 * Build a measurement with the given parameters 88 * 89 * @param weight weight of the measurement in the least squares problem 90 * @param measuredValue measured value 91 * @param ignored true if the measurement should be ignored 92 */ 93 public WeightedMeasurement(double weight, double measuredValue, 94 boolean ignored) { 95 this.weight = weight; 96 this.measuredValue = measuredValue; 97 this.ignored = ignored; 98 } 99 100 /** 101 * Get the weight of the measurement in the least squares problem 102 * 103 * @return weight 104 */ 105 public double getWeight() { 106 return weight; 107 } 108 109 /** 110 * Get the measured value 111 * 112 * @return measured value 113 */ 114 public double getMeasuredValue() { 115 return measuredValue; 116 } 117 118 /** 119 * Get the residual for this measurement 120 * The residual is the measured value minus the theoretical value. 121 * 122 * @return residual 123 */ 124 public double getResidual() { 125 return measuredValue - getTheoreticalValue(); 126 } 127 128 /** 129 * Get the theoretical value expected for this measurement 130 * <p>The theoretical value is the value expected for this measurement 131 * if the model and its parameter were all perfectly known.</p> 132 * <p>The value must be computed using the current estimate of the parameters 133 * set by the solver in the problem.</p> 134 * 135 * @return theoretical value 136 */ 137 public abstract double getTheoreticalValue(); 138 139 /** 140 * Get the partial derivative of the {@link #getTheoreticalValue 141 * theoretical value} according to the parameter. 142 * <p>The value must be computed using the current estimate of the parameters 143 * set by the solver in the problem.</p> 144 * 145 * @param parameter parameter against which the partial derivative 146 * should be computed 147 * @return partial derivative of the {@link #getTheoreticalValue 148 * theoretical value} 149 */ 150 public abstract double getPartial(EstimatedParameter parameter); 151 152 /** 153 * Set the ignore flag to the specified value 154 * Setting the ignore flag to true allow to reject wrong 155 * measurements, which sometimes can be detected only rather late. 156 * 157 * @param ignored value for the ignore flag 158 */ 159 public void setIgnored(boolean ignored) { 160 this.ignored = ignored; 161 } 162 163 /** 164 * Check if this measurement should be ignored 165 * 166 * @return true if the measurement should be ignored 167 */ 168 public boolean isIgnored() { 169 return ignored; 170 } 171 172 } 173
