public static POMDPState getNewState(Domain d) {
POMDPState s = new POMDPState();
ObjectClass doorClass = d.getObjectClass(Names.CLASS_DOOR);
ObjectClass indexerClass = d.getObjectClass(Names.CLASS_INDEXER);
ObjectInstance indexer = new ObjectInstance(indexerClass, Names.OBJ_INDEXER);
indexer.setValue(Names.ATTR_INDEX, 0);
s.addObject(indexer);
ObjectInstance leftDoor = new ObjectInstance(doorClass, Names.OBJ_LEFT_DOOR);
ObjectInstance rightDoor = new ObjectInstance(doorClass, Names.OBJ_RIGHT_DOOR);
leftDoor.setValue(Names.ATTR_POSITION, Names.LEFT);
rightDoor.setValue(Names.ATTR_POSITION, Names.RIGHT);
boolean doorChoice = new java.util.Random().nextBoolean();
leftDoor.setValue(Names.ATTR_TIGERNESS, doorChoice ? 0 : 1);
rightDoor.setValue(Names.ATTR_TIGERNESS, doorChoice ? 1 : 0);
s.addObject(leftDoor);
s.addObject(rightDoor);
return s;
}
public static State getExampleState(Domain domain) {
State s = new State();
ObjectInstance agent = new ObjectInstance(domain.getObjectClass(CLASSAGENT), "agent0");
agent.setValue(ATTX, 0);
agent.setValue(ATTY, 0);
ObjectInstance location = new ObjectInstance(domain.getObjectClass(CLASSLOCATION), "location0");
location.setValue(ATTX, 10);
location.setValue(ATTY, 10);
s.addObject(agent);
s.addObject(location);
return s;
}
@Override
protected State performActionHelper(State s, String[] params) {
// get agent and current position
ObjectInstance agent = s.getFirstObjectOfClass(CLASSAGENT);
int curX = agent.getDiscValForAttribute(ATTX);
int curY = agent.getDiscValForAttribute(ATTY);
// sample directon with random roll
double r = Math.random();
double sumProb = 0.;
int dir = 0;
for (int i = 0; i < this.directionProbs.length; i++) {
sumProb += this.directionProbs[i];
if (r < sumProb) {
dir = i;
break; // found direction
}
}
// get resulting position
int[] newPos = this.moveResult(curX, curY, dir);
// set the new position
agent.setValue(ATTX, newPos[0]);
agent.setValue(ATTY, newPos[1]);
// return the state we just modified
return s;
}
@Override
public List<TransitionProbability> getTransitions(State s, String[] params) {
// get agent and current position
ObjectInstance agent = s.getFirstObjectOfClass(CLASSAGENT);
int curX = agent.getDiscValForAttribute(ATTX);
int curY = agent.getDiscValForAttribute(ATTY);
List<TransitionProbability> tps = new ArrayList<TransitionProbability>(4);
TransitionProbability noChangeTransition = null;
for (int i = 0; i < this.directionProbs.length; i++) {
int[] newPos = this.moveResult(curX, curY, i);
if (newPos[0] != curX || newPos[1] != curY) {
// new possible outcome
State ns = s.copy();
ObjectInstance nagent = ns.getFirstObjectOfClass(CLASSAGENT);
nagent.setValue(ATTX, newPos[0]);
nagent.setValue(ATTY, newPos[1]);
// create transition probability object and add to our list of outcomes
tps.add(new TransitionProbability(ns, this.directionProbs[i]));
} else {
// this direction didn't lead anywhere new
// if there are existing possible directions that wouldn't lead anywhere, aggregate with
// them
if (noChangeTransition != null) {
noChangeTransition.p += this.directionProbs[i];
} else {
// otherwise create this new state and transition
noChangeTransition = new TransitionProbability(s.copy(), this.directionProbs[i]);
tps.add(noChangeTransition);
}
}
}
return tps;
}