1 | package genius.core.analysis;
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2 |
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3 | import java.io.BufferedReader;
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4 | import java.io.File;
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5 | import java.io.FileReader;
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6 | import java.io.IOException;
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7 | import java.util.ArrayList;
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8 | import java.util.List;
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9 |
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10 | import genius.core.Bid;
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11 | import genius.core.BidIterator;
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12 | import genius.core.Domain;
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13 | import genius.core.exceptions.AnalysisException;
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14 | import genius.core.utility.AbstractUtilitySpace;
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15 | import genius.core.utility.AdditiveUtilitySpace;
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16 | import genius.core.utility.UtilitySpace;
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17 |
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18 | /**
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19 | * A collection of utilityspaces can be viewed as a space in which a bid is
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20 | * assigned multiple point corresponding to the utility of the bid for different
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21 | * agents. We refer to this space as a BidSpace. This class allows to calculate
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22 | * the properties of this space.
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23 | *
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24 | * @author Dmytro Tykhonov, Tim Baarslag, Wouter Pasman
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25 | */
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26 | public class BidSpace {
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27 |
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28 | /** Collection of utility spaces constituting the space. */
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29 | private AbstractUtilitySpace[] utilspaces;
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30 | /** Domain of the utility spaces. */
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31 | private Domain domain;
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32 | /** List of all bidpoints in the domain. */
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33 | public ArrayList<BidPoint> bidPoints;
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34 |
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35 | /** Cached Pareto frontier. */
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36 | List<BidPoint> paretoFrontier = null; // null if not yet computed
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37 | /**
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38 | * Cached Kalai-Smorodinsky solution. The solution is assumed to be unique.
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39 | */
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40 | BidPoint kalaiSmorodinsky = null; // null if not yet computed
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41 | /** Cached Nash solution. The solution is assumed to be unique. */
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42 | BidPoint nash = null; // null if not yet computed
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43 |
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44 | /**
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45 | * Default constructor used to construct a multidimensional bidding space.
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46 | * Warning: this call iterates over ALL possible bids.
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47 | *
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48 | * @param utilityspaces
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49 | * of which the bidding space consists.
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50 | * @throws Exception
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51 | * is thrown when one of the utility spaces is corrupt.
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52 | */
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53 | public BidSpace(AbstractUtilitySpace... utilityspaces) throws Exception {
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54 | initializeUtilitySpaces(utilityspaces);
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55 | buildSpace(true);
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56 | }
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57 |
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58 | /**
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59 | * Constructor to createFrom a BidSpace given exactly two utility spaces.
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60 | * The main difference is that if excludeBids is true, then only the bid
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61 | * points are saved. This has is a good way to save memory. Warning: this
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62 | * call iterates over ALL possible bids.
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63 | *
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64 | * @param utilityspaceA
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65 | * utilityspace of agent A.
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66 | * @param utilityspaceB
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67 | * utilityspace of agent B.
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68 | * @param excludeBids
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69 | * if the real bids should be saved or not.
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70 | * @throws Exception
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71 | * is thrown when one of the utility spaces is corrupt.
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72 | */
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73 | public BidSpace(AbstractUtilitySpace utilityspaceA, AbstractUtilitySpace utilityspaceB, boolean excludeBids)
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74 | throws Exception {
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75 | AbstractUtilitySpace[] spaces = { utilityspaceA, utilityspaceB };
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76 | initializeUtilitySpaces(spaces);
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77 | buildSpace(excludeBids);
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78 | }
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79 |
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80 | /**
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81 | * Constructor which is identical to its three parameter version, except for
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82 | * the argument skipCheckSpaceB. Independent of the value of this parameter,
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83 | * this constructor skips the security checks for the second utilityspace.
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84 | * This is interesting if you use the utility of an opponent model in which
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85 | * some variables of the utilityspace may not be set. Warning: this call
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86 | * iterates over ALL possible bids.
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87 | *
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88 | * @param utilityspaceA
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89 | * utilityspace of agent A.
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90 | * @param utilityspaceB
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91 | * utilityspace of agent B.
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92 | * @param excludeBids
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93 | * if the real bids should be saved or not.
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94 | * @param skipCheckSpaceB
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95 | * skip security checks for the utilityspace of agent B.
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96 | * @throws Exception
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97 | * if something goes wrong when calculating the utility of a
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98 | * bid.
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99 | */
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100 | public BidSpace(AbstractUtilitySpace utilityspaceA, AbstractUtilitySpace utilityspaceB, boolean excludeBids,
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101 | boolean skipCheckSpaceB) throws Exception {
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102 | if (utilityspaceA == null || utilityspaceB == null)
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103 | throw new NullPointerException("util space is null");
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104 | AbstractUtilitySpace[] spaces = { utilityspaceA, utilityspaceB };
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105 | utilspaces = spaces.clone();
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106 | domain = utilspaces[0].getDomain();
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107 | utilityspaceA.checkReadyForNegotiation(domain);
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108 | buildSpace(excludeBids);
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109 | }
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110 |
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111 | /**
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112 | * Initializes the utility spaces by checking if they are valid. This
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113 | * procedure also clones the spaces such that manipulating them is not
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114 | * useful for an agent.
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115 | *
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116 | * @param utilityspaces
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117 | * to be initialized and validated.
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118 | * @throws Exception
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119 | * if one of the utility spaces is null.
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120 | */
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121 | private void initializeUtilitySpaces(AbstractUtilitySpace[] utilityspaces) throws Exception {
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122 | utilspaces = utilityspaces.clone();
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123 | for (UtilitySpace utilitySpace : utilityspaces) {
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124 | if (utilitySpace == null)
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125 | throw new NullPointerException("util space is null: " + utilityspaces);
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126 | }
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127 | domain = utilspaces[0].getDomain();
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128 | for (AbstractUtilitySpace space : utilityspaces) {
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129 | space.checkReadyForNegotiation(domain);
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130 | }
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131 | }
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132 |
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133 | // RA: This method checks whether or not the Pareto file exists
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134 | private boolean checkParetoFileExist(String filePathStr) {
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135 |
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136 | File f = new File(filePathStr);
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137 | if (f.exists())
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138 | return true;
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139 | else
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140 | return false;
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141 | }
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142 |
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143 | private void readParetoFromFile(String fileName, boolean isAgentAHasProfile1) {
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144 |
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145 | this.paretoFrontier = new ArrayList<BidPoint>();
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146 | this.bidPoints = new ArrayList<BidPoint>();
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147 | try {
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148 | FileReader input = new FileReader(fileName);
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149 | BufferedReader bufRead = new BufferedReader(input);
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150 | String line;
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151 | Double[] utility = new Double[2];
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152 | do {
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153 | line = bufRead.readLine();
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154 | if (line != null) {
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155 | int index = line.indexOf(",");
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156 | if (index > 0) {
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157 | if (isAgentAHasProfile1) {
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158 | utility[0] = Double.parseDouble(line.substring(0, line.indexOf(",")));
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159 | utility[1] = Double.parseDouble(line.substring(line.indexOf(",") + 1));
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160 | } else {
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161 | utility[1] = Double.parseDouble(line.substring(0, line.indexOf(",")));
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162 | utility[0] = Double.parseDouble(line.substring(line.indexOf(",") + 1));
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163 | }
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164 |
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165 | BidPoint bidpt = new BidPoint(null, utility);
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166 | this.paretoFrontier.add(bidpt);
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167 | }
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168 | }
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169 |
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170 | } while (line != null);
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171 |
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172 | } catch (IOException e) {
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173 | // If another exception is generated, print a stack trace
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174 | e.printStackTrace();
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175 | }
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176 |
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177 | System.out.println(this.paretoFrontier);
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178 | }
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179 |
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180 | /**
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181 | * Create the space with all bid points from all the
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182 | * {@link AdditiveUtilitySpace}s.
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183 | *
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184 | * @param excludeBids
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185 | * if true do not store the real bids.
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186 | * @throws exception
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187 | * if utility can not be computed for some point.
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188 | */
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189 | private void buildSpace(boolean excludeBids) throws Exception {
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190 |
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191 | String fname = utilspaces[0].getFileName();
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192 | if (fname == null) {
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193 | fname = "";
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194 | }
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195 |
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196 | // RA:
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197 | if (fname.contains("profile-1.xml")) {
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198 | String fileName = fname.replaceAll("profile-1.xml", "pareto.xml");
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199 | if (checkParetoFileExist(fileName)) {
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200 | readParetoFromFile(fileName, true);
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201 | return;
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202 | }
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203 | } else if (fname.contains("profile-2.xml")) {
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204 | String fileName = fname.replaceAll("profile-2.xml", "pareto.xml");
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205 | if (checkParetoFileExist(fileName)) {
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206 | readParetoFromFile(fileName, false);
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207 | return;
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208 | }
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209 | }
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210 |
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211 | bidPoints = new ArrayList<BidPoint>();
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212 | BidIterator lBidIter = new BidIterator(domain);
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213 |
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214 | // if low memory mode, do not store the actual. At the time of writing
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215 | // this
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216 | // has no side-effects
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217 | while (lBidIter.hasNext()) {
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218 | Bid bid = lBidIter.next();
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219 | Double[] utils = new Double[utilspaces.length];
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220 | for (int i = 0; i < utilspaces.length; i++) {
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221 | utils[i] = utilspaces[i].getUtility(bid);
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222 | }
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223 | if (excludeBids) {
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224 | bidPoints.add(new BidPoint(null, utils));
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225 | } else {
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226 | bidPoints.add(new BidPoint(bid, utils));
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227 | }
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228 | }
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229 | // System.out.println("Real outcome space:");
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230 | // System.out.println(bidPoints);
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231 | }
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232 |
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233 | /**
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234 | * Returns the Pareto fronier. If the Pareto frontier is unknown, then it is
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235 | * computed using an efficient algorithm. If the utilityspace contains more
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236 | * than 500000 bids, then a suboptimal algorithm is used.
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237 | *
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238 | * @return The Pareto frontier. The order is ascending utilityA.
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239 | * @throws Exception
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240 | * if the utility of a bid can not be calculated.
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241 | */
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242 | public List<BidPoint> getParetoFrontier() throws Exception {
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243 | boolean isBidSpaceAvailable = !bidPoints.isEmpty();
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244 | if (paretoFrontier == null) {
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245 | if (isBidSpaceAvailable) {
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246 | paretoFrontier = computeParetoFrontier(bidPoints).getFrontier();
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247 | return paretoFrontier;
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248 | }
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249 |
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250 | ArrayList<BidPoint> subPareto = new ArrayList<BidPoint>();
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251 | BidIterator lBidIter = new BidIterator(domain);
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252 | ArrayList<BidPoint> tmpBidPoints = new ArrayList<BidPoint>();
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253 | boolean isSplitted = false;
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254 | int count = 0;
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255 | while (lBidIter.hasNext()) {
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256 | Bid bid = lBidIter.next();
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257 | Double[] utils = new Double[utilspaces.length];
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258 | for (int i = 0; i < utilspaces.length; i++)
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259 | utils[i] = utilspaces[i].getUtility(bid);
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260 | tmpBidPoints.add(new BidPoint(bid, utils));
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261 | count++;
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262 | if (count > 500000) {
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263 | subPareto.addAll(computeParetoFrontier(tmpBidPoints).getFrontier());
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264 | tmpBidPoints = new ArrayList<BidPoint>();
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265 | count = 0;
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266 | isSplitted = true;
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267 | }
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268 | }
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269 | // Add the remainder to the sub-Pareto frontier
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270 | if (tmpBidPoints.size() > 0)
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271 | subPareto.addAll(computeParetoFrontier(tmpBidPoints).getFrontier());
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272 |
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273 | if (isSplitted)
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274 | paretoFrontier = computeParetoFrontier(subPareto).getFrontier(); // merge
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275 | // sub-pareto's
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276 | else
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277 | paretoFrontier = subPareto;
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278 | }
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279 | return paretoFrontier;
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280 | }
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281 |
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282 | /**
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283 | * Private because it should be called only with the bids as built by
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284 | * BuildSpace.
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285 | *
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286 | * @param points
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287 | * the ArrayList<BidPoint> as computed by BuildSpace and stored
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288 | * in bidpoints.
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289 | * @return the sorted pareto frontier of the bidpoints.
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290 | * @throws Exception
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291 | * if problem occurs
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292 | */
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293 | private ParetoFrontier computeParetoFrontier(List<BidPoint> points) throws Exception {
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294 | ParetoFrontier frontier = new ParetoFrontier();
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295 | for (BidPoint p : points)
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296 | frontier.mergeIntoFrontier(p);
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297 |
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298 | frontier.sort();
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299 | return frontier;
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300 | }
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301 |
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302 | /**
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303 | * Method which returns a list of the Pareto efficient bids.
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304 | *
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305 | * @return Pareto-efficient bids.
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306 | * @throws Exception
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307 | * if the utility of a bid cannot be calculated
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308 | */
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309 | public List<Bid> getParetoFrontierBids() throws Exception {
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310 | ArrayList<Bid> bids = new ArrayList<Bid>();
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311 | List<BidPoint> points = getParetoFrontier();
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312 | for (BidPoint p : points)
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313 | bids.add(p.getBid());
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314 | return bids;
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315 | }
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316 |
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317 | /**
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318 | * Calculates Kalai-Smorodinsky optimal outcome. Assumes that Pareto
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319 | * frontier is already built. Kalai-Smorodinsky is the point on
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320 | * paretofrontier that has least difference in utilities for A and B.
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321 | *
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322 | * @return the Kalai-Smorodinsky BidPoint.
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323 | * @throws Exception
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324 | * when the Pareto frontier is invalid.
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325 | */
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326 | public BidPoint getKalaiSmorodinsky() throws Exception {
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327 | if (kalaiSmorodinsky != null)
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328 | return kalaiSmorodinsky;
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329 | if (getParetoFrontier().size() < 1)
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330 | throw new AnalysisException("kalaiSmorodinsky product: Pareto frontier is unavailable.");
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331 | double asymmetry = 2; // every point in space will have lower asymmetry
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332 | // than this.
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333 | for (BidPoint p : paretoFrontier) {
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334 | double asymofp = 0;
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335 | for (int i = 0; i < utilspaces.length; i++) {
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336 | for (int j = i + 1; j < utilspaces.length; j++) {
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337 | asymofp += Math.abs(p.getUtility(i) - p.getUtility(j));
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338 | }
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339 | }
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340 |
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341 | if (asymofp < asymmetry) {
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342 | kalaiSmorodinsky = p;
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343 | asymmetry = asymofp;
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344 | }
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345 | }
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346 | return kalaiSmorodinsky;
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347 | }
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348 |
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349 | /**
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350 | * Calculates the undiscounted Nash optimal outcome. Assumes that Pareto
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351 | * frontier is already built. Nash is the point on paretofrontier that has
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352 | * max product of utilities for A and B.
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353 | *
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354 | * @return the Nash BidPoint.
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355 | * @throws Exception
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356 | * when the Pareto frontier is invalid.
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357 | */
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358 | public BidPoint getNash() throws Exception {
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359 | if (nash != null)
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360 | return nash;
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361 | if (getParetoFrontier().size() < 1)
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362 | throw new AnalysisException("Nash product: Pareto frontier is unavailable.");
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363 | double maxp = -1;
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364 | double[] agentResValue = new double[utilspaces.length];
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365 | for (int i = 0; i < utilspaces.length; i++)
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366 | if (utilspaces[i].getReservationValue() != null)
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367 | agentResValue[i] = utilspaces[i].getReservationValue();
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368 | else
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369 | agentResValue[i] = .0;
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370 | for (BidPoint p : paretoFrontier) {
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371 | double utilofp = 1;
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372 | for (int i = 0; i < utilspaces.length; i++)
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373 | utilofp = utilofp * (p.getUtility(i) - agentResValue[i]);
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374 |
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375 | if (utilofp > maxp) {
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376 | nash = p;
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377 | maxp = utilofp;
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378 | }
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379 | }
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380 | return nash;
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381 | }
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382 |
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383 | /**
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384 | * Returns the nearest Pareto-optimal bid given the opponent's utility
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385 | * (agent B).
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386 | *
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387 | * @param opponentUtility
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388 | * the utility for the opponent.
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389 | * @return the utility of us on the pareto curve.
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390 | * @throws Exception
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391 | * if getPareto fails or other cases, e.g. paretoFrontier
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392 | * contains utilityB = NaN, which may occur if the opponent
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393 | * model creating the utility space is corrupt.
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394 | */
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395 | public double ourUtilityOnPareto(double opponentUtility) throws Exception {
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396 |
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397 | if (opponentUtility < 0. || opponentUtility > 1.)
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398 | throw new Exception("opponentUtil " + opponentUtility + " is out of [0,1].");
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399 | List<BidPoint> pareto = getParetoFrontier();
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400 | // our utility is along A axis, opp util along B axis.
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401 |
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402 | // add endpoints to pareto curve such that utilB spans [0,1] entirely
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403 | if (pareto.get(0).getUtility(1) < 1)
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404 | pareto.add(0, new BidPoint(null, new Double[] { 0., 1. }));
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405 | if (pareto.get(pareto.size() - 1).getUtility(1) > 0)
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406 | pareto.add(new BidPoint(null, new Double[] { 1., 0. }));
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407 | if (pareto.size() < 2)
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408 | throw new Exception("Pareto has only 1 point?!" + pareto);
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409 | // pareto is monotonically descending in utilB direction.
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410 | int i = 0;
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411 | while (!(pareto.get(i).getUtility(1) >= opponentUtility && opponentUtility > pareto.get(i + 1).getUtility(1)))
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412 | i++;
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413 |
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414 | double oppUtil1 = pareto.get(i).getUtility(1); // this is the high value
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415 | double oppUtil2 = pareto.get(i + 1).getUtility(1); // the low value
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416 | double f = (opponentUtility - oppUtil1) / (oppUtil2 - oppUtil1); // f in
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417 | // [0,1]
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418 | // is
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419 | // relative
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420 | // distance
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421 | // from
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422 | // point
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423 | // i.
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424 | // close to point i means f~0. close to i+1 means f~1
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425 | double lininterpol = (1 - f) * pareto.get(i).getUtility(0) + f * pareto.get(i + 1).getUtility(0);
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426 | return lininterpol;
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427 | }
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428 |
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429 | /**
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430 | * @return string representation of the BidSpace, which is basically a long
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431 | * list of all bid its bid points.
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432 | */
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433 | public String toString() {
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434 | return bidPoints.toString();
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435 | }
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436 |
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437 | /**
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438 | * Finds the bid with the minimal distance
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439 | * weightA*DeltaUtilA^2+weightB*DeltaUtilB^2 where DeltaUtilA is the
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440 | * difference between given utilA and the actual utility of the bid.
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441 | *
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442 | * @param utilA
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443 | * the agent-A utility of the point to be found.
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444 | * @param utilB
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445 | * the agent-B utility of the point to be found.
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446 | * @param weightA
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447 | * weight in A direction.
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448 | * @param weightB
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449 | * weight in B direction.
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450 | * @param excludeList
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451 | * Bids to be excluded from the search.
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452 | * @return best point, or null if none remaining.
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453 | */
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454 | public BidPoint getNearestBidPoint(double utilA, double utilB, double weightA, double weightB,
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455 | ArrayList<Bid> excludeList) {
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456 | System.out.println("determining nearest bid to " + utilA + "," + utilB);
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457 | System.out.println("excludes=" + excludeList);
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458 | double mindist = 9.; // paretospace distances are always smaller than 2
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459 | BidPoint bestPoint = null;
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460 | double r;
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461 | for (BidPoint p : bidPoints) {
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462 | boolean contains = false;
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463 | for (Bid b : excludeList) {
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464 | if (b.equals(p.getBid())) {
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465 | contains = true;
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466 | break;
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467 | }
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468 | }
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469 | if (contains)
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470 | continue;
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471 | r = weightA * Math.pow((p.getUtility(0) - utilA), 2) + weightB * Math.pow((p.getUtility(1) - utilB), 2);
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472 | if (r < mindist) {
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473 | mindist = r;
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474 | bestPoint = p;
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475 | }
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476 | }
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477 | System.out.println("point found=" + bestPoint.getBid());
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478 | if (excludeList.size() > 1)
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479 | System.out.println("bid equals exclude(1):" + bestPoint.getBid().equals(excludeList.get(1)));
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480 | return bestPoint;
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481 | }
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482 |
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483 | /**
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484 | * Method which given a bid point determines the distance to the nearest
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485 | * Pareto-optimal bid. If the distance is small, than the bid is near
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486 | * Pareto-optimal.
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487 | *
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488 | * @param bid
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489 | * for which the smallest distance to the Pareto frontier is
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490 | * found.
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491 | * @return distance to the nearest Pareto-optimal bid.
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492 | */
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493 | public double distanceToNearestParetoBid(BidPoint bid) {
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494 | if (paretoFrontier == null) {
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495 | try {
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496 | paretoFrontier = getParetoFrontier();
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497 | } catch (Exception e) {
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498 | e.printStackTrace();
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499 | }
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500 | }
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501 | double distance = Double.POSITIVE_INFINITY;
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502 | for (BidPoint paretoBid : paretoFrontier) {
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503 | double paretoDistance = bid.getDistance(paretoBid);
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504 | if (paretoDistance < distance) {
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505 | distance = paretoDistance;
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506 | }
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507 | }
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508 | return distance;
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509 | }
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510 | } |
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