edu.columbia.cs.coms4701.search.online
Interface OnlineHeuristicFunction<K extends AgentAction,S extends AgentState,P extends OnlineSearchProblem<K,S>>


public interface OnlineHeuristicFunction<K extends AgentAction,S extends AgentState,P extends OnlineSearchProblem<K,S>>

A heuristic function in an online environment directly evaluates states, rather than search tree nodes.

A problem-specific function h(s) = the estimated cost of the cheapest path from state s to a goal state.

Heuristic functions have one formal constraint: if s is a goal node, h(s) = 0.

A heuristic function is consistent or monotonic if, for every state s and every successor s' generated by any action a, the estimated cost of reaching the goal from s is no greater than the step cost of getting to s' plus the estimated cost of reaching the goal from s'.

Implementations should presumably be customized to a particular type of problem.

Version:
0.1

User: aaron Date: Sep 22, 2006 Time: 11:48:05 AM

Author:
aaron@cs

Method Summary
 double estimate(S theState)
          Estimates the cost from the given state to the closest goal state.
 

Method Detail

estimate

double estimate(S theState)
Estimates the cost from the given state to the closest goal state.

If the given state *is* a goal node, should return zero.

Parameters:
theState -
Returns:
estimated cost from this state to a goal state.