git.gag.com Git - debian/openrocket/blob - core/src/net/sf/openrocket/optimization/rocketoptimization/RocketOptimizationFunction.java

   1 package net.sf.openrocket.optimization.rocketoptimization;
   2
   3 import java.util.ArrayList;
   4 import java.util.Arrays;
   5 import java.util.List;
   6
   7 import net.sf.openrocket.document.Simulation;
   8 import net.sf.openrocket.logging.LogHelper;
   9 import net.sf.openrocket.optimization.general.Function;
  10 import net.sf.openrocket.optimization.general.OptimizationException;
  11 import net.sf.openrocket.optimization.general.Point;
  12 import net.sf.openrocket.rocketcomponent.Rocket;
  13 import net.sf.openrocket.startup.Application;
  14 import net.sf.openrocket.unit.UnitGroup;
  15 import net.sf.openrocket.unit.Value;
  16 import net.sf.openrocket.util.Pair;
  17
  18 /**
  19  * A Function that optimizes a specific RocketOptimizationParameter to some goal
  20  * by modifying a base simulation using SimulationModifiers.
  21  *
  22  * @author Sampo Niskanen <sampo.niskanen@iki.fi>
  23  */
  24 public class RocketOptimizationFunction implements Function {
  25         private static final LogHelper log = Application.getLogger();
  26
  27         private static final double OUTSIDE_DOMAIN_SCALE = 1.0e200;
  28
  29         /*
  30          * NOTE:  This class must be thread-safe!!!
  31          */
  32
  33         private final Simulation baseSimulation;
  34         private final OptimizableParameter parameter;
  35         private final OptimizationGoal goal;
  36         private final SimulationDomain domain;
  37         private final SimulationModifier[] modifiers;
  38
  39
  40         private final List<RocketOptimizationListener> listeners = new ArrayList<RocketOptimizationListener>();
  41
  42
  43         /**
  44          * Sole constructor.
  45          * <p>
  46          * The dimensionality of the resulting function is the same as the length of the
  47          * modifiers array.
  48          *
  49          * @param baseSimulation        the base simulation to modify
  50          * @param parameter                     the rocket parameter to optimize
  51          * @param goal                          the goal of the rocket parameter
  52          * @param modifiers                     the modifiers that modify the simulation
  53          */
  54         public RocketOptimizationFunction(Simulation baseSimulation, OptimizableParameter parameter,
  55                         OptimizationGoal goal, SimulationDomain domain, SimulationModifier... modifiers) {
  56                 this.baseSimulation = baseSimulation;
  57                 this.parameter = parameter;
  58                 this.goal = goal;
  59                 this.domain = domain;
  60                 this.modifiers = modifiers.clone();
  61                 if (modifiers.length == 0) {
  62                         throw new IllegalArgumentException("No SimulationModifiers specified");
  63                 }
  64         }
  65
  66
  67         @Override
  68         public double evaluate(Point point) throws InterruptedException, OptimizationException {
  69
  70                 /*
  71                  * parameterValue is the computed parameter value (e.g. altitude)
  72                  * goalValue is the value that needs to be minimized
  73                  */
  74                 double goalValue, parameterValue;
  75
  76                 log.debug("Computing optimization function value at point " + point);
  77
  78                 // Create the new simulation based on the point
  79                 double[] p = point.asArray();
  80                 if (p.length != modifiers.length) {
  81                         throw new IllegalArgumentException("Point has length " + p.length + " while function has " +
  82                                         modifiers.length + " simulation modifiers");
  83                 }
  84
  85                 Simulation simulation = newSimulationInstance(baseSimulation);
  86                 for (int i = 0; i < modifiers.length; i++) {
  87                         modifiers[i].modify(simulation, p[i]);
  88                 }
  89
  90
  91                 // Check whether the point is within the simulation domain
  92                 Pair<Double, Value> d = domain.getDistanceToDomain(simulation);
  93                 double distance = d.getU();
  94                 Value referenceValue = d.getV();
  95                 if (distance > 0 || Double.isNaN(distance)) {
  96                         if (Double.isNaN(distance)) {
  97                                 goalValue = Double.MAX_VALUE;
  98                         } else {
  99                                 goalValue = (distance + 1) * OUTSIDE_DOMAIN_SCALE;
 100                         }
 101                         log.debug("Optimization point is outside of domain, distance=" + distance + " goal function value=" + goalValue);
 102
 103                         fireEvent(simulation, point, referenceValue, null, goalValue);
 104
 105                         return goalValue;
 106                 }
 107
 108
 109                 // Compute the optimization value
 110                 parameterValue = parameter.computeValue(simulation);
 111                 goalValue = goal.getMinimizationParameter(parameterValue);
 112
 113                 if (Double.isNaN(goalValue)) {
 114                         log.warn("Computed goal value was NaN, baseSimulation=" + baseSimulation + " parameter=" + parameter +
 115                                         " goal=" + goal + " modifiers=" + Arrays.toString(modifiers) + " simulation=" + simulation +
 116                                         " parameter value=" + parameterValue);
 117                         goalValue = Double.MAX_VALUE;
 118                 }
 119
 120                 log.verbose("Parameter value at point " + point + " is " + parameterValue + ", goal function value=" + goalValue);
 121
 122                 fireEvent(simulation, point, referenceValue, new Value(parameterValue, parameter.getUnitGroup().getDefaultUnit()),
 123                                 goalValue);
 124
 125                 return goalValue;
 126         }
 127
 128
 129
 130
 131
 132         /**
 133          * Returns a new deep copy of the simulation and rocket.  This methods performs
 134          * synchronization on the simulation for thread protection.
 135          * <p>
 136          * Note:  This method is package-private for unit testing purposes.
 137          *
 138          * @return      a new deep copy of the simulation and rocket
 139          */
 140         Simulation newSimulationInstance(Simulation simulation) {
 141                 synchronized (baseSimulation) {
 142                         Rocket newRocket = simulation.getRocket().copyWithOriginalID();
 143                         Simulation newSimulation = simulation.duplicateSimulation(newRocket);
 144                         return newSimulation;
 145                 }
 146         }
 147
 148
 149         /**
 150          * Add a listener to this function.  The listener will be notified each time the
 151          * function is successfully evaluated.
 152          * <p>
 153          * Note that the listener may be called from other threads and must be thread-safe!
 154          *
 155          * @param listener      the listener to add.
 156          */
 157         public void addRocketOptimizationListener(RocketOptimizationListener listener) {
 158                 listeners.add(listener);
 159         }
 160
 161         public void removeRocketOptimizationListener(RocketOptimizationListener listener) {
 162                 listeners.remove(listener);
 163         }
 164
 165
 166
 167         private void fireEvent(Simulation simulation, Point p, Value domainReference, Value parameterValue, double goalValue)
 168                         throws OptimizationException {
 169
 170                 if (listeners.isEmpty()) {
 171                         return;
 172                 }
 173
 174
 175                 Value[] values = new Value[p.dim()];
 176                 for (int i = 0; i < values.length; i++) {
 177                         double value = modifiers[i].getCurrentSIValue(simulation);
 178                         UnitGroup unit = modifiers[i].getUnitGroup();
 179                         values[i] = new Value(value, unit.getDefaultUnit());
 180                 }
 181
 182                 for (RocketOptimizationListener l : listeners) {
 183                         l.evaluated(p, values, domainReference, parameterValue, goalValue);
 184                 }
 185         }
 186 }