burlap.behavior.singleagent.auxiliary

Class StateReachability

java.lang.Object

burlap.behavior.singleagent.auxiliary.StateReachability

public class StateReachability
extends java.lang.Object

This class provides methods for finding the set of reachable states from a source state. Alternate methods for finding the reachable states under a specific policy are also provided. See the Java doc for each method for more information.

Author:

James MacGlashan

Field Summary

Fields

Modifier and Type	Field and Description
static int	debugID The debugID used for making calls to DPrint.

Constructor Summary

Constructors

Constructor and Description
StateReachability()

Method Summary

Methods

Modifier and Type	Method and Description
static java.util.Set<HashableState>	getPolicyReachableHashedStates(Policy p, State from, HashableStateFactory usingHashFactory) Finds the set of states (HashableState) that are reachable under a policy from a source state.
static java.util.Set<HashableState>	getPolicyReachableHashedStates(Policy p, State from, HashableStateFactory usingHashFactory, TerminalFunction tf) Finds the set of states (HashableState) that are reachable under a policy from a source state.
static java.util.List<State>	getPolicyReachableStates(Policy p, State from, HashableStateFactory usingHashFactory) Finds the set of states that are reachable under a policy from a source state.
static java.util.List<State>	getPolicyReachableStates(Policy p, State from, HashableStateFactory usingHashFactory, TerminalFunction tf) Finds the set of states that are reachable under a policy from a source state.
static java.util.Set<HashableState>	getReachableHashedStates(State from, SADomain inDomain, HashableStateFactory usingHashFactory) Returns the set of State objects that are reachable from a source state.
static java.util.Set<HashableState>	getReachableHashedStates(State from, SADomain inDomain, HashableStateFactory usingHashFactory, TerminalFunction tf) Returns the set of State objects that are reachable from a source state.
static java.util.List<State>	getReachableStates(State from, SADomain inDomain, HashableStateFactory usingHashFactory) Returns the list of State objects that are reachable from a source state.
static java.util.List<State>	getReachableStates(State from, SADomain inDomain, HashableStateFactory usingHashFactory, TerminalFunction tf) Returns the list of State objects that are reachable from a source state.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

debugID

public static int debugID

The debugID used for making calls to DPrint.

Constructor Detail

StateReachability

public StateReachability()

Method Detail

getReachableStates

public static java.util.List<State> getReachableStates(State from,
                                       SADomain inDomain,
                                       HashableStateFactory usingHashFactory)

Returns the list of State objects that are reachable from a source state.

Parameters:

from - the source state

inDomain - the domain of the state

usingHashFactory - the state hashing factory to use for indexing states and testing equality.

Returns:

the list of State objects that are reachable from a source state.

getReachableStates

public static java.util.List<State> getReachableStates(State from,
                                       SADomain inDomain,
                                       HashableStateFactory usingHashFactory,
                                       TerminalFunction tf)

Returns the list of State objects that are reachable from a source state.

Parameters:

from - the source state

inDomain - the domain of the state

usingHashFactory - the state hashing factory to use for indexing states and testing equality.

tf - a terminal function that prevents expansion from terminal states.

Returns:

the list of State objects that are reachable from a source state.

getReachableHashedStates

public static java.util.Set<HashableState> getReachableHashedStates(State from,
                                                    SADomain inDomain,
                                                    HashableStateFactory usingHashFactory)

Returns the set of State objects that are reachable from a source state.

Parameters:

from - the source state

inDomain - the domain of the state

usingHashFactory - the state hashing factory to use for indexing states and testing equality.

Returns:

the set of State objects that are reachable from a source state.

getReachableHashedStates

public static java.util.Set<HashableState> getReachableHashedStates(State from,
                                                    SADomain inDomain,
                                                    HashableStateFactory usingHashFactory,
                                                    TerminalFunction tf)

Returns the set of State objects that are reachable from a source state.

Parameters:

from - the source state

inDomain - the domain of the state

usingHashFactory - the state hashing factory to use for indexing states and testing equality.

tf - a terminal function that prevents expansion from terminal states.

Returns:

the set of State objects that are reachable from a source state.

getPolicyReachableStates

public static java.util.List<State> getPolicyReachableStates(Policy p,
                                             State from,
                                             HashableStateFactory usingHashFactory)

Finds the set of states that are reachable under a policy from a source state. Reachability under a source policy means that the space of actions considered are those that have non-zero probability of being selected by the policy and all possible outcomes of those states are considered.

Parameters:

p - the policy that must be followed

from - the source State from which the policy would be initiated.

usingHashFactory - the HashableStateFactory used to hash states and test equality.

Returns:

a List of State objects that could be reached.

getPolicyReachableStates

public static java.util.List<State> getPolicyReachableStates(Policy p,
                                             State from,
                                             HashableStateFactory usingHashFactory,
                                             TerminalFunction tf)

Finds the set of states that are reachable under a policy from a source state. Reachability under a source policy means that the space of actions considered are those that have non-zero probability of being selected by the policy and all possible outcomes of those states are considered.

Parameters:

p - the policy that must be followed

from - the source State from which the policy would be initiated.

usingHashFactory - the HashableStateFactory used to hash states and test equality.

tf - a TerminalFunction that prevents further state expansion from states that are terminal states.

Returns:

a List of State objects that could be reached.

getPolicyReachableHashedStates

public static java.util.Set<HashableState> getPolicyReachableHashedStates(Policy p,
                                                          State from,
                                                          HashableStateFactory usingHashFactory)

Finds the set of states (HashableState) that are reachable under a policy from a source state. Reachability under a source policy means that the space of actions considered are those that have non-zero probability of being selected by the policy and all possible outcomes of those states are considered.

Parameters:

p - the policy that must be followed

from - the source State from which the policy would be initiated.

usingHashFactory - the HashableStateFactory used to hash states and test equality.

Returns:

a Set of HashableState objects that could be reached.

getPolicyReachableHashedStates

public static java.util.Set<HashableState> getPolicyReachableHashedStates(Policy p,
                                                          State from,
                                                          HashableStateFactory usingHashFactory,
                                                          TerminalFunction tf)

Finds the set of states (HashableState) that are reachable under a policy from a source state. Reachability under a source policy means that the space of actions considered are those that have non-zero probability of being selected by the policy and all possible outcomes of those states are considered.

Parameters:

p - the policy that must be followed

from - the source State from which the policy would be initiated.

usingHashFactory - the HashableStateFactory used to hash states and test equality.

tf - a TerminalFunction that prevents further state expansion from states that are terminal states.

Returns:

a Set of HashableState objects that could be reached.