[339] | 1 | /**
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| 2 | *
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| 3 | */
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| 4 | package bargainingchips.analysis;
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| 5 |
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| 6 | import java.io.BufferedReader;
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| 7 | import java.io.File;
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| 8 | import java.io.FileReader;
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| 9 | import java.io.IOException;
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| 10 | import java.util.ArrayList;
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| 11 | import java.util.List;
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| 12 |
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| 13 | import bargainingchips.Bundle;
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| 14 | import bargainingchips.OutcomeSpace;
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| 15 | import bargainingchips.analysis.BundleUtilityPoint;
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| 16 | import bargainingchips.analysis.ParetoFrontier;
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| 17 | import bargainingchips.utilityfunctions.UtilityFunction;
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| 18 |
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| 19 |
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| 20 | /**
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| 21 | *
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| 22 | * BundleUtilitySpace is a collection of outcomespaces which can be viewed as a space in which a bundle is assigned
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| 23 | * multiple point corresponding to the utility of the bundle for different agents. It contains functions (adapting
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| 24 | * {@link genius.core.analysis.BidSpace}) for calculating Nash product, Pareto frontier, and Kalai-Smorodinsky solution.
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| 25 | *
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| 26 | *
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| 27 | * @author Faria Nassiri-Mofakham
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| 28 | *
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| 29 | */
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| 30 |
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| 31 | public class BundleUtilitySpace
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| 32 | {
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| 33 | /** Collection of utility spaces constituting the space. */
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| 34 | private OutcomeSpace[] outcomespaces;
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| 35 | /** Domain of the utility spaces. */
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| 36 | //private Domain domain;
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| 37 | private List<Bundle> domain;
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| 38 | /** List of all bundlepoints in the domain. */
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| 39 | public ArrayList<BundleUtilityPoint> bundlePoints;
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| 40 |
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| 41 | private UtilityFunction[] utilities;
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| 42 |
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| 43 |
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| 44 | /** Cached Pareto frontier. */
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| 45 | List<BundleUtilityPoint> paretoFrontier = null; // null if not yet computed
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| 46 | /**
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| 47 | * Cached Kalai-Smorodinsky solution. The solution is assumed to be unique.
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| 48 | */
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| 49 | BundleUtilityPoint kalaiSmorodinsky = null; // null if not yet computed
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| 50 | /** Cached Nash solution. The solution is assumed to be unique. */
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| 51 | BundleUtilityPoint nash = null; // null if not yet computed
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| 52 |
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| 53 | /**
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| 54 | * Default constructor used to construct a multidimensional bidding space.
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| 55 | * Warning: this call iterates over ALL possible bids.
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| 56 | *
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| 57 | * @param utilityspaces
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| 58 | * of which the bidding space consists.
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| 59 | * @throws Exception
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| 60 | * is thrown when one of the utility spaces is corrupt.
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| 61 | */
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| 62 | public BundleUtilitySpace(OutcomeSpace... utilityspaces) throws Exception {
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| 63 | initializeUtilitySpaces(utilityspaces);
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| 64 | buildSpace(true);
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| 65 | }
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| 66 |
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| 67 | /**
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| 68 | * Constructor to createFrom a BidSpace given exactly two utility spaces.
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| 69 | * The main difference is that if excludeBids is true, then only the bid
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| 70 | * points are saved. This has is a good way to save memory. Warning: this
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| 71 | * call iterates over ALL possible bids.
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| 72 | *
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| 73 | * @param outcomespaceA
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| 74 | * outcomespace of agent A.
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| 75 | * @param outcomespaceB
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| 76 | * outcomespace of agent B.
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| 77 | * @param excludeBids
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| 78 | * if the real bids should be saved or not.
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| 79 | * @throws Exception
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| 80 | * is thrown when one of the utility spaces is corrupt.
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| 81 | */
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| 82 | public BundleUtilitySpace(OutcomeSpace outcomespaceA, OutcomeSpace outcomespaceB, boolean excludeBids)
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| 83 | throws Exception {
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| 84 | OutcomeSpace[] spaces = { outcomespaceA, outcomespaceB };
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| 85 | initializeUtilitySpaces(spaces);
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| 86 | buildSpace(excludeBids);
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| 87 | }
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| 88 |
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| 89 | /**
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| 90 | * Constructor which is identical to its three parameter version, except for
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| 91 | * the argument skipCheckSpaceB. Independent of the value of this parameter,
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| 92 | * this constructor skips the security checks for the second utilityspace.
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| 93 | * This is interesting if you use the utility of an opponent model in which
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| 94 | * some variables of the utilityspace may not be set. Warning: this call
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| 95 | * iterates over ALL possible bids.
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| 96 | *
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| 97 | * @param outcomespaceA
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| 98 | * outcomespace of agent A.
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| 99 | * @param outcomespaceB
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| 100 | * outcomespace of agent B.
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| 101 | * @param excludeBids
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| 102 | * if the real bids should be saved or not.
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| 103 | * @param skipCheckSpaceB
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| 104 | * skip security checks for the outcomespace of agent B.
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| 105 | * @throws Exception
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| 106 | * if something goes wrong when calculating the utility of a
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| 107 | * bid.
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| 108 | */
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| 109 | public BundleUtilitySpace(OutcomeSpace outcomespaceA, OutcomeSpace outcomespaceB, boolean excludeBids,
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| 110 | boolean skipCheckSpaceB) throws Exception {
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| 111 | if (outcomespaceA == null || outcomespaceB == null)
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| 112 | throw new NullPointerException("util space is null");
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| 113 | OutcomeSpace[] spaces = { outcomespaceA, outcomespaceB };
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| 114 | outcomespaces = spaces.clone();
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| 115 | domain = outcomespaces[0].getAllBids();
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| 116 | outcomespaceA.checkReadyForNegotiation(domain);
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| 117 | buildSpace(excludeBids);
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| 118 | }
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| 119 |
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| 120 | /**
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| 121 | * Initializes the utility spaces by checking if they are valid. This
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| 122 | * procedure also clones the spaces such that manipulating them is not
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| 123 | * useful for an agent.
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| 124 | *
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| 125 | * @param utilityspaces
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| 126 | * to be initialized and validated.
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| 127 | * @throws Exception
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| 128 | * if one of the utility spaces is null.
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| 129 | */
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| 130 | private void initializeUtilitySpaces(OutcomeSpace[] utilityspaces) throws Exception {
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| 131 | outcomespaces = utilityspaces.clone();
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| 132 | for (OutcomeSpace utilitySpace : outcomespaces) {
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| 133 | if (utilitySpace == null)
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| 134 | throw new NullPointerException("util space is null: " + utilityspaces);
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| 135 | }
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| 136 | domain = outcomespaces[0].getAllBids();
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| 137 | for (OutcomeSpace space : utilityspaces) {
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| 138 | space.checkReadyForNegotiation(domain);
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| 139 | }
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| 140 | }
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| 141 |
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| 142 | // RA: This method checks whether or not the Pareto file exists
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| 143 | private boolean checkParetoFileExist(String filePathStr) {
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| 144 |
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| 145 | File f = new File(filePathStr);
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| 146 | if (f.exists())
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| 147 | return true;
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| 148 | else
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| 149 | return false;
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| 150 | }
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| 151 |
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| 152 | private void readParetoFromFile(String fileName, boolean isAgentAHasProfile1) {
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| 153 |
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| 154 | this.paretoFrontier = new ArrayList<BundleUtilityPoint>();
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| 155 | this.bundlePoints = new ArrayList<BundleUtilityPoint>();
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| 156 | try {
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| 157 | FileReader input = new FileReader(fileName);
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| 158 |
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| 159 | @SuppressWarnings("resource")
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| 160 |
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| 161 | BufferedReader bufRead = new BufferedReader(input);
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| 162 | String line;
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| 163 | Double[] utility = new Double[2];
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| 164 | do {
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| 165 | line = bufRead.readLine();
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| 166 | if (line != null) {
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| 167 | int index = line.indexOf(",");
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| 168 | if (index > 0) {
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| 169 | if (isAgentAHasProfile1) {
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| 170 | utility[0] = Double.parseDouble(line.substring(0, line.indexOf(",")));
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| 171 | utility[1] = Double.parseDouble(line.substring(line.indexOf(",") + 1));
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| 172 | } else {
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| 173 | utility[1] = Double.parseDouble(line.substring(0, line.indexOf(",")));
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| 174 | utility[0] = Double.parseDouble(line.substring(line.indexOf(",") + 1));
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| 175 | }
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| 176 |
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| 177 | BundleUtilityPoint bidpt = new BundleUtilityPoint(null, utility);
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| 178 | this.paretoFrontier.add(bidpt);
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| 179 | }
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| 180 | }
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| 181 |
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| 182 | } while (line != null);
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| 183 |
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| 184 | } catch (IOException e) {
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| 185 | // If another exception is generated, print a stack trace
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| 186 | e.printStackTrace();
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| 187 | }
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| 188 |
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| 189 | System.out.println(this.paretoFrontier);
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| 190 | }
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| 191 |
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| 192 | /**
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| 193 | * Create the space with all bid points from all the
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| 194 | * {@link AdditiveUtilitySpace}s.
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| 195 | *
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| 196 | * @param excludeBids
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| 197 | * if true do not store the real bids.
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| 198 | * @throws exception
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| 199 | * if utility can not be computed for some point.
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| 200 | */
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| 201 | private void buildSpace(boolean excludeBids) throws Exception {
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| 202 |
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| 203 | String fname = outcomespaces[0].getName();
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| 204 | if (fname == null) {
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| 205 | fname = "";
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| 206 | }
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| 207 |
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| 208 | // RA:
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| 209 | if (fname.contains("profile-1.xml")) {
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| 210 | String fileName = fname.replaceAll("profile-1.xml", "pareto.xml");
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| 211 | if (checkParetoFileExist(fileName)) {
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| 212 | readParetoFromFile(fileName, true);
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| 213 | return;
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| 214 | }
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| 215 | } else if (fname.contains("profile-2.xml")) {
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| 216 | String fileName = fname.replaceAll("profile-2.xml", "pareto.xml");
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| 217 | if (checkParetoFileExist(fileName)) {
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| 218 | readParetoFromFile(fileName, false);
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| 219 | return;
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| 220 | }
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| 221 | }
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| 222 |
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| 223 | bundlePoints = new ArrayList<BundleUtilityPoint>();
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| 224 | //BidIterator lBidIter = new BidIterator(domain);
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| 225 |
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| 226 | // if low memory mode, do not store the actual. At the time of writing
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| 227 | // this
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| 228 | // has no side-effects
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| 229 |
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| 230 | for (Bundle bid : domain)
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| 231 | {
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| 232 | Double[] utils = new Double[outcomespaces.length];
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| 233 | for (int i = 0; i < outcomespaces.length; i++) {
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| 234 | utils[i] = outcomespaces[i].getUtility(utilities[i] ,bid);
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| 235 | }
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| 236 | if (excludeBids) {
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| 237 | bundlePoints.add(new BundleUtilityPoint(null, utils));
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| 238 | } else {
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| 239 | bundlePoints.add(new BundleUtilityPoint(bid, utils));
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| 240 | }
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| 241 |
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| 242 | }
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| 243 | }
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| 244 |
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| 245 | /**
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| 246 | * Returns the Pareto fronier. If the Pareto frontier is unknown, then it is
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| 247 | * computed using an efficient algorithm. If the utilityspace contains more
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| 248 | * than 500000 bids, then a suboptimal algorithm is used.
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| 249 | *
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| 250 | * @return The Pareto frontier. The order is ascending utilityA.
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| 251 | * @throws Exception
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| 252 | * if the utility of a bid can not be calculated.
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| 253 | */
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| 254 | public List<BundleUtilityPoint> getParetoFrontier() throws Exception {
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| 255 | boolean isBidSpaceAvailable = !bundlePoints.isEmpty();
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| 256 | if (paretoFrontier == null) {
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| 257 | if (isBidSpaceAvailable) {
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| 258 | paretoFrontier = computeParetoFrontier(bundlePoints).getFrontier();
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| 259 | return paretoFrontier;
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| 260 | }
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| 261 |
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| 262 | ArrayList<BundleUtilityPoint> subPareto = new ArrayList<BundleUtilityPoint>();
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| 263 |
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| 264 | //BidIterator lBidIter = new BidIterator(domain);
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| 265 |
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| 266 | ArrayList<BundleUtilityPoint> tmpBundleUtilityPoints = new ArrayList<BundleUtilityPoint>();
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| 267 | boolean isSplitted = false;
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| 268 | int count = 0;
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| 269 |
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| 270 | for (Bundle bid : domain)
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| 271 | {
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| 272 | Double[] utils = new Double[outcomespaces.length];
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| 273 | for (int i = 0; i < outcomespaces.length; i++)
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| 274 | utils[i] = outcomespaces[i].getUtility(utilities[i] ,bid);
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| 275 |
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| 276 | tmpBundleUtilityPoints.add(new BundleUtilityPoint(bid, utils));
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| 277 | count++;
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| 278 | if (count > 500000) {
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| 279 | subPareto.addAll(computeParetoFrontier(tmpBundleUtilityPoints).getFrontier());
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| 280 | tmpBundleUtilityPoints = new ArrayList<BundleUtilityPoint>();
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| 281 | count = 0;
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| 282 | isSplitted = true;
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| 283 | }
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| 284 | }
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| 285 |
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| 286 | // Add the remainder to the sub-Pareto frontier
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| 287 | if (tmpBundleUtilityPoints.size() > 0)
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| 288 | subPareto.addAll(computeParetoFrontier(tmpBundleUtilityPoints).getFrontier());
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| 289 |
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| 290 | if (isSplitted)
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| 291 | paretoFrontier = computeParetoFrontier(subPareto).getFrontier(); // merge
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| 292 | // sub-pareto's
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| 293 | else
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| 294 | paretoFrontier = subPareto;
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| 295 | }
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| 296 | return paretoFrontier;
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| 297 | }
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| 298 |
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| 299 | /**
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| 300 | * Private because it should be called only with the bids as built by
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| 301 | * BuildSpace.
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| 302 | *
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| 303 | * @param points
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| 304 | * the ArrayList<BundleUtilityPoint> as computed by BuildSpace and stored
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| 305 | * in bidpoints.
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| 306 | * @return the sorted pareto frontier of the bidpoints.
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| 307 | * @throws Exception
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| 308 | * if problem occurs
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| 309 | */
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| 310 | private ParetoFrontier computeParetoFrontier(List<BundleUtilityPoint> points) throws Exception {
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| 311 | ParetoFrontier frontier = new ParetoFrontier();
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| 312 | for (BundleUtilityPoint p : points)
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| 313 | frontier.mergeIntoFrontier(p);
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| 314 |
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| 315 | frontier.sort();
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| 316 | return frontier;
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| 317 | }
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| 318 |
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| 319 | /**
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| 320 | * Method which returns a list of the Pareto efficient bids.
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| 321 | *
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| 322 | * @return Pareto-efficient bids.
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| 323 | * @throws Exception
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| 324 | * if the utility of a bid cannot be calculated
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| 325 | */
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| 326 | public List<Bundle> getParetoFrontierBids() throws Exception {
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| 327 | ArrayList<Bundle> bids = new ArrayList<Bundle>();
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| 328 | List<BundleUtilityPoint> points = getParetoFrontier();
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| 329 | for (BundleUtilityPoint p : points)
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| 330 | bids.add(p.getBundle());
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| 331 | return bids;
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| 332 | }
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| 333 |
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| 334 | /**
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| 335 | * Calculates Kalai-Smorodinsky optimal outcome. Assumes that Pareto
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| 336 | * frontier is already built. Kalai-Smorodinsky is the point on
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| 337 | * paretofrontier that has least difference in utilities for A and B.
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| 338 | *
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| 339 | * @return the Kalai-Smorodinsky BundleUtilityPoint.
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| 340 | * @throws Exception
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| 341 | * when the Pareto frontier is invalid.
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| 342 | */
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| 343 | public BundleUtilityPoint getKalaiSmorodinsky() throws Exception {
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| 344 | if (kalaiSmorodinsky != null)
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| 345 | return kalaiSmorodinsky;
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| 346 | if (getParetoFrontier().size() < 1)
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| 347 | throw new Exception("kalaiSmorodinsky product: Pareto frontier is unavailable.");
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| 348 | double asymmetry = 2; // every point in space will have lower asymmetry
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| 349 | // than this.
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| 350 | for (BundleUtilityPoint p : paretoFrontier) {
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| 351 | double asymofp = 0;
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| 352 | for (int i = 0; i < outcomespaces.length; i++) {
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| 353 | for (int j = i + 1; j < outcomespaces.length; j++) {
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| 354 | asymofp += Math.abs(p.getUtility(i) - p.getUtility(j));
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| 355 | }
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| 356 | }
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| 357 |
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| 358 | if (asymofp < asymmetry) {
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| 359 | kalaiSmorodinsky = p;
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| 360 | asymmetry = asymofp;
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| 361 | }
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| 362 | }
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| 363 | return kalaiSmorodinsky;
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| 364 | }
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| 365 |
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| 366 | /**
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| 367 | * Calculates the undiscounted Nash optimal outcome. Assumes that Pareto
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| 368 | * frontier is already built. Nash is the point on paretofrontier that has
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| 369 | * max product of utilities for A and B.
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| 370 | *
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| 371 | * @return the Nash BundleUtilityPoint.
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| 372 | * @throws Exception
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| 373 | * when the Pareto frontier is invalid.
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| 374 | */
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| 375 | public BundleUtilityPoint getNash() throws Exception {
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| 376 | if (nash != null)
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| 377 | return nash;
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| 378 | if (getParetoFrontier().size() < 1)
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| 379 | throw new Exception("Nash product: Pareto frontier is unavailable.");
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| 380 | double maxp = -1;
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| 381 | double[] agentResValue = new double[outcomespaces.length];
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| 382 | for (int i = 0; i < outcomespaces.length; i++)
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| 383 | try {
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| 384 | agentResValue[i] = outcomespaces[i].getReservationValue(utilities[i]);
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| 385 | }
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| 386 | catch (Exception e) {
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| 387 | //e.printStackTrace();
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| 388 | agentResValue[i] = .0;
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| 389 | }
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| 390 | for (BundleUtilityPoint p : paretoFrontier) {
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| 391 | double utilofp = 1;
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| 392 | for (int i = 0; i < outcomespaces.length; i++)
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| 393 | utilofp = utilofp * (p.getUtility(i) - agentResValue[i]);
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| 394 |
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| 395 | if (utilofp > maxp) {
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| 396 | nash = p;
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| 397 | maxp = utilofp;
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| 398 | }
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| 399 | }
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| 400 | return nash;
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| 401 | }
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| 402 |
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| 403 | /**
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| 404 | * Returns the nearest Pareto-optimal bid given the opponent's utility
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| 405 | * (agent B).
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| 406 | *
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| 407 | * @param opponentUtility
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| 408 | * the utility for the opponent.
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| 409 | * @return the utility of us on the pareto curve.
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| 410 | * @throws Exception
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| 411 | * if getPareto fails or other cases, e.g. paretoFrontier
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| 412 | * contains utilityB = NaN, which may occur if the opponent
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| 413 | * model creating the utility space is corrupt.
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| 414 | */
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| 415 | public double ourUtilityOnPareto(double opponentUtility) throws Exception {
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| 416 |
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| 417 | if (opponentUtility < 0. || opponentUtility > 1.)
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| 418 | throw new Exception("opponentUtil " + opponentUtility + " is out of [0,1].");
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| 419 | List<BundleUtilityPoint> pareto = getParetoFrontier();
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| 420 | // our utility is along A axis, opp util along B axis.
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| 421 |
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| 422 | // add endpoints to pareto curve such that utilB spans [0,1] entirely
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| 423 | if (pareto.get(0).getUtility(1) < 1)
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| 424 | pareto.add(0, new BundleUtilityPoint(null, new Double[] { 0., 1. }));
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| 425 | if (pareto.get(pareto.size() - 1).getUtility(1) > 0)
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| 426 | pareto.add(new BundleUtilityPoint(null, new Double[] { 1., 0. }));
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| 427 | if (pareto.size() < 2)
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| 428 | throw new Exception("Pareto has only 1 point?!" + pareto);
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| 429 | // pareto is monotonically descending in utilB direction.
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| 430 | int i = 0;
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| 431 | while (!(pareto.get(i).getUtility(1) >= opponentUtility && opponentUtility > pareto.get(i + 1).getUtility(1)))
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| 432 | i++;
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| 433 |
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| 434 | double oppUtil1 = pareto.get(i).getUtility(1); // this is the high value
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| 435 | double oppUtil2 = pareto.get(i + 1).getUtility(1); // the low value
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| 436 | double f = (opponentUtility - oppUtil1) / (oppUtil2 - oppUtil1); // f in
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| 437 | // [0,1]
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| 438 | // is
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| 439 | // relative
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| 440 | // distance
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| 441 | // from
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| 442 | // point
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| 443 | // i.
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| 444 | // close to point i means f~0. close to i+1 means f~1
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| 445 | double lininterpol = (1 - f) * pareto.get(i).getUtility(0) + f * pareto.get(i + 1).getUtility(0);
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| 446 | return lininterpol;
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| 447 | }
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| 448 |
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| 449 | /**
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| 450 | * @return string representation of the BidSpace, which is basically a long
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| 451 | * list of all bid its bid points.
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| 452 | */
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| 453 | public String toString() {
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| 454 | return bundlePoints.toString();
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| 455 | }
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| 456 |
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| 457 | /**
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| 458 | * Finds the bid with the minimal distance
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| 459 | * weightA*DeltaUtilA^2+weightB*DeltaUtilB^2 where DeltaUtilA is the
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| 460 | * difference between given utilA and the actual utility of the bid.
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| 461 | *
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| 462 | * @param utilA
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| 463 | * the agent-A utility of the point to be found.
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| 464 | * @param utilB
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| 465 | * the agent-B utility of the point to be found.
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| 466 | * @param weightA
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| 467 | * weight in A direction.
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| 468 | * @param weightB
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| 469 | * weight in B direction.
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| 470 | * @param excludeList
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| 471 | * Bids to be excluded from the search.
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| 472 | * @return best point, or null if none remaining.
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| 473 | */
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| 474 | public BundleUtilityPoint getNearestBundleUtilityPoint(double utilA, double utilB, double weightA, double weightB,
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| 475 | ArrayList<Bundle> excludeList) {
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| 476 | System.out.println("determining nearest bid to " + utilA + "," + utilB);
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| 477 | System.out.println("excludes=" + excludeList);
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| 478 | double mindist = 9.; // paretospace distances are always smaller than 2
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| 479 | BundleUtilityPoint bestPoint = null;
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| 480 | double r;
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| 481 | for (BundleUtilityPoint p : bundlePoints) {
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| 482 | boolean contains = false;
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| 483 | for (Bundle b : excludeList) {
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| 484 | if (b.equals(p.getBundle())) {
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| 485 | contains = true;
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| 486 | break;
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| 487 | }
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| 488 | }
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| 489 | if (contains)
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| 490 | continue;
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| 491 | r = weightA * Math.pow((p.getUtility(0) - utilA), 2) + weightB * Math.pow((p.getUtility(1) - utilB), 2);
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| 492 | if (r < mindist) {
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| 493 | mindist = r;
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| 494 | bestPoint = p;
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| 495 | }
|
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| 496 | }
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| 497 | System.out.println("point found=" + bestPoint.getBundle());
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| 498 | if (excludeList.size() > 1)
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| 499 | System.out.println("bid equals exclude(1):" + bestPoint.getBundle().equals(excludeList.get(1)));
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| 500 | return bestPoint;
|
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| 501 | }
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| 502 |
|
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| 503 | /**
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| 504 | * Method which given a bid point determines the distance to the nearest
|
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| 505 | * Pareto-optimal bid. If the distance is small, than the bid is near
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| 506 | * Pareto-optimal.
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| 507 | *
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| 508 | * @param bid
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| 509 | * for which the smallest distance to the Pareto frontier is
|
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| 510 | * found.
|
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| 511 | * @return distance to the nearest Pareto-optimal bid.
|
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| 512 | */
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| 513 | public double distanceToNearestParetoBid(BundleUtilityPoint bid) {
|
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| 514 | if (paretoFrontier == null) {
|
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| 515 | try {
|
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| 516 | paretoFrontier = getParetoFrontier();
|
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| 517 | } catch (Exception e) {
|
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| 518 | e.printStackTrace();
|
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| 519 | }
|
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| 520 | }
|
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| 521 | double distance = Double.POSITIVE_INFINITY;
|
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| 522 | for (BundleUtilityPoint paretoBid : paretoFrontier) {
|
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| 523 | double paretoDistance = bid.getDistance(paretoBid);
|
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| 524 | if (paretoDistance < distance) {
|
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| 525 | distance = paretoDistance;
|
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| 526 | }
|
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| 527 | }
|
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| 528 | return distance;
|
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| 529 | }
|
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| 530 | } |
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