diff options
Diffstat (limited to 'nlpsolver/ThirdParty/EvolutionarySolver/src/net/adaptivebox/sco/SCAgent.java')
-rw-r--r-- | nlpsolver/ThirdParty/EvolutionarySolver/src/net/adaptivebox/sco/SCAgent.java | 143 |
1 files changed, 143 insertions, 0 deletions
diff --git a/nlpsolver/ThirdParty/EvolutionarySolver/src/net/adaptivebox/sco/SCAgent.java b/nlpsolver/ThirdParty/EvolutionarySolver/src/net/adaptivebox/sco/SCAgent.java new file mode 100644 index 000000000..a09d0dcfd --- /dev/null +++ b/nlpsolver/ThirdParty/EvolutionarySolver/src/net/adaptivebox/sco/SCAgent.java @@ -0,0 +1,143 @@ +package net.adaptivebox.sco; + +/** + * Description: The description of social cognitive agent. + * + * @Information source: a) external library (L); b) the own memory: a point that + * generated in the last learning cycle + * + * @Coefficients: TaoB and TaoW + * + * @ Author Create/Modi Note + * Xiaofeng Xie Mar 11, 2003 + * Xiaofeng Xie May 11, 2004 + * Xiaofeng Xie May 20, 2004 + * + * This library is free software; you can redistribute it and/or + * modify it under the terms of the GNU Lesser General Public + * License as published by the Free Software Foundation; either + * version 2.1 of the License, or (at your option) any later version. + * + * This library is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * Lesser General Public License for more details. + * + * Please acknowledge the author(s) if you use this code in any way. + * + * @version 1.0 + * @Since MAOS1.0 + * + * @References: + * [1] Xie X F, Zhang W J. Solving engineering design problems by social cognitive + * optimization. Genetic and Evolutionary Computation Conference, 2004: 261-262 + */ + +import net.adaptivebox.problem.ProblemEncoder; +import net.adaptivebox.space.DesignSpace; +import net.adaptivebox.space.ILocationEngine; +import net.adaptivebox.global.RandomGenerator; +import net.adaptivebox.goodness.IGoodnessCompareEngine; +import net.adaptivebox.knowledge.Library; +import net.adaptivebox.knowledge.SearchPoint; + +public class SCAgent { + + // Describes the problem to be solved (encode the point into intermediate information) + private ProblemEncoder problemEncoder; + + // Forms the goodness landscape + private IGoodnessCompareEngine specComparator; + + // the coefficients of SCAgent + private static final int TaoB = 2; + + // The early version set TaoW as the size of external library (NL), but 4 is often enough + private static final int TaoW = 4; + + // The referred external library + private Library externalLib; + + // store the point that generated in current learning cycle + private SearchPoint trailPoint; + + // the own memory: store the point that generated in last learning cycle + private SearchPoint pcurrent_t; + + public void setExternalLib(Library lib) { + externalLib = lib; + } + + public void setProblemEncoder(ProblemEncoder encoder) { + problemEncoder = encoder; + trailPoint = problemEncoder.getFreshSearchPoint(); + pcurrent_t = problemEncoder.getEncodedSearchPoint(); + } + + public void setSpecComparator(IGoodnessCompareEngine comparer) { + specComparator = comparer; + } + + public SearchPoint generatePoint() { + // generate a new point + generatePoint(trailPoint); + + // evaluate the generated point + problemEncoder.evaluate(trailPoint); + return trailPoint; + } + + private void generatePoint(ILocationEngine tempPoint) { + SearchPoint Xmodel, Xrefer, libBPoint; + + // choose Selects a better point (libBPoint) from externalLib (L) based + // on tournament selection + int xb = externalLib.tournamentSelection(specComparator, TaoB, true); + libBPoint = externalLib.getSelectedPoint(xb); + + // Compares pcurrent_t with libBPoint + // The better one becomes model point (Xmodel) + // The worse one becomes refer point (Xrefer) + if (specComparator.compare(pcurrent_t.getEncodeInfo(), + libBPoint.getEncodeInfo()) == IGoodnessCompareEngine.LARGER_THAN) { + Xmodel = libBPoint; + Xrefer = pcurrent_t; + } else { + Xmodel = pcurrent_t; + Xrefer = libBPoint; + } + + // observational learning: generates a new point near the model point, which + // the variation range is decided by the difference of Xmodel and Xrefer + inferPoint(tempPoint, Xmodel, Xrefer, problemEncoder.getDesignSpace()); + } + + // 1. Update the current point into the external library + // 2. Replace the current point by the generated point + public void updateInfo() { + // Selects a bad point kw from TaoW points in Library + int xw = externalLib.tournamentSelection(specComparator, TaoW, false); + + // Replaces kw with pcurrent_t + externalLib.getSelectedPoint(xw).importPoint(pcurrent_t); + + // Replaces pcurrent_t (x(t)) with trailPoint (x(t+1)) + pcurrent_t.importPoint(trailPoint); + } + + // 1---model point, 2---refer point + private boolean inferPoint(ILocationEngine newPoint, ILocationEngine point1, ILocationEngine point2, + DesignSpace space) { + double[] newLoc = newPoint.getLocation(); + double[] real1 = point1.getLocation(); + double[] real2 = point2.getLocation(); + + for (int i = 0; i < newLoc.length; i++) { + newLoc[i] = real1[i] * 2 - real2[i]; + // boundary handling + newLoc[i] = space.boundAdjustAt(newLoc[i], i); + newLoc[i] = RandomGenerator.doubleRangeRandom(newLoc[i], real2[i]); + } + return true; + } +} |