TabularBeliefState

java.lang.Object
- burlap.mdp.singleagent.pomdp.beliefstate.TabularBeliefState

All Implemented Interfaces:

MutableState, State, BeliefState, DenseBeliefVector, EnumerableBeliefState, HashableState
```
public class TabularBeliefState
extends java.lang.Object
implements BeliefState, EnumerableBeliefState, DenseBeliefVector, MutableState, HashableState
```
A class for storing a sparse tabular representation of the belief state. That is, each MDP state is assigned a unique identifier using a StateEnumerator and this class uses a Map to associated the probability mass with each state. MDP states that have zero mass are not stored in the map.
If using a BeliefMDP solver with a TabularBeliefState, it is recommended that you use the ReflectiveHashableStateFactory, since TabularBeliefState implements HashableState and since you probably do not want to do abstraction of the belief state.

Nested Class Summary
- Nested classes/interfaces inherited from interface burlap.mdp.singleagent.pomdp.beliefstate.EnumerableBeliefState
  EnumerableBeliefState.StateBelief

Field Summary

Fields
Modifier and Type	Field and Description
`protected java.util.Map<java.lang.Integer,java.lang.Double>`	`beliefValues` The belief vector, stored sparsely with a `Map`.
`protected PODomain`	`domain` The POMDP domain with which this belief state is associated.
`protected StateEnumerator`	`stateEnumerator` A state enumerator for determining the index of MDP states in the belief vector.

Constructor Summary

Constructors
Constructor and Description
`TabularBeliefState()`
`TabularBeliefState(PODomain domain)`
`TabularBeliefState(PODomain domain, StateEnumerator stateEnumerator)` Constructs a new `TabularBeliefState`.
`TabularBeliefState(TabularBeliefState srcBeliefState)` Constructs a new `TabularBeliefState` from a source `TabularBeliefState`.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`double`	`belief(int stateId)` Returns the value of the belief vector for the provided index.
`double`	`belief(State s)` Returns the probability density/mass for the input MDP state.
`double[]`	`beliefVector()` Returns this belief state as a dense (non-sparse) belief vector.
`State`	`copy()` Returns a copy of this state suitable for creating state transitions.
`boolean`	`equals(java.lang.Object obj)`
`java.lang.Object`	`get(java.lang.Object variableKey)` Returns the value for the given variable key.
`java.util.Map<java.lang.Integer,java.lang.Double>`	`getBeliefValues()`
`PODomain`	`getDomain()`
`StateEnumerator`	`getStateEnumerator()`
`java.util.List<State>`	`getStateSpace()` Returns the set of underlying MDP states this belief vector spans.
`int`	`hashCode()`
`void`	`initializeAllBeliefValuesTo(double initialValue)` Initializes the probability mass of all underlying MDP states to the specified value.
`void`	`initializeBeliefsUniformly()` Initializes this belief state to a uniform distribution
`java.util.List<EnumerableBeliefState.StateBelief>`	`nonZeroBeliefs()` Returns the states, and their probability mass, that have non-zero probability mass.
`int`	`numStates()` Returns the size of the observed underlying MDP state space.
`State`	`s()` Returns the underlying source state that is hashed.
`State`	`sample()` Samples an MDP state state from this belief distribution.
`MutableState`	`set(java.lang.Object variableKey, java.lang.Object value)` Sets the value for the given variable key.
`void`	`setBelief(int stateId, double b)` Sets the probability mass (belief) associated with the underlying MDP state.
`void`	`setBelief(State s, double b)` Sets the probability mass (belief) associated with the underlying MDP state.
`void`	`setBeliefValues(java.util.Map<java.lang.Integer,java.lang.Double> beliefValues)`
`void`	`setBeliefVector(double[] b)` Sets this belief state to the provided.
`void`	`setDomain(PODomain domain)`
`void`	`setStateEnumerator(StateEnumerator stateEnumerator)`
`State`	`stateForId(int id)` Returns the corresponding MDP state for the provided unique identifier.
`java.lang.String`	`toString()`
`java.util.List<java.lang.Object>`	`variableKeys()` Returns the list of state variable keys.
`void`	`zeroOutBeliefVector()` Sets this belief state to have zero probability mass for all underlying MDP states.

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

- Field Detail
  - stateEnumerator
```
protected StateEnumerator stateEnumerator
```
    A state enumerator for determining the index of MDP states in the belief vector.
  - beliefValues
```
protected java.util.Map<java.lang.Integer,java.lang.Double> beliefValues
```
    The belief vector, stored sparsely with a Map.
  - domain
```
protected PODomain domain
```
    The POMDP domain with which this belief state is associated. Contains the ObservationFunction necessary to perform belief state updates.
- Constructor Detail
  - TabularBeliefState
```
public TabularBeliefState()
```
  - TabularBeliefState
```
public TabularBeliefState(TabularBeliefState srcBeliefState)
```
    Constructs a new TabularBeliefState from a source TabularBeliefState. Changes to the new state or source state will not affect the other.
    
    Parameters:
    
    srcBeliefState - the source TabularBeliefState to copy.
  - TabularBeliefState
```
public TabularBeliefState(PODomain domain)
```
  - TabularBeliefState
```
public TabularBeliefState(PODomain domain,
                          StateEnumerator stateEnumerator)
```
    Constructs a new TabularBeliefState.
    
    Parameters:
    
    domain - the PODomain domain to which the belief state is associated.
    
    stateEnumerator - a StateEnumerator to index the states in the belief vector.
- Method Detail
  - getStateEnumerator
```
public StateEnumerator getStateEnumerator()
```
  - setStateEnumerator
```
public void setStateEnumerator(StateEnumerator stateEnumerator)
```
  - getBeliefValues
```
public java.util.Map<java.lang.Integer,java.lang.Double> getBeliefValues()
```
  - setBeliefValues
```
public void setBeliefValues(java.util.Map<java.lang.Integer,java.lang.Double> beliefValues)
```
  - getDomain
```
public PODomain getDomain()
```
  - setDomain
```
public void setDomain(PODomain domain)
```
  - belief
```
public double belief(State s)
```
    Description copied from interface: BeliefState
    
    Returns the probability density/mass for the input MDP state.
    
    Specified by:
    
    belief in interface BeliefState
    
    Parameters:
    
    s - the the input MDP state defined by a State instance.
    
    Returns:
    
    the probability density/mass of the input MDP state in this belief distribution.
  - belief
```
public double belief(int stateId)
```
    Returns the value of the belief vector for the provided index.
    
    Parameters:
    
    stateId - the index (state identification number) of the belief vector to return.
    
    Returns:
    
    the value of the belief vector for the provided index.
  - sample
```
public State sample()
```
    Description copied from interface: BeliefState
    
    Samples an MDP state state from this belief distribution.
    
    Specified by:
    
    sample in interface BeliefState
    
    Returns:
    
    an MDP state defined by a State instance.
  - nonZeroBeliefs
```
public java.util.List<EnumerableBeliefState.StateBelief> nonZeroBeliefs()
```
    Description copied from interface: EnumerableBeliefState
    
    Returns the states, and their probability mass, that have non-zero probability mass. States that are not included in the returned listed are assumed to have probability mass zero.
    
    Specified by:
    
    nonZeroBeliefs in interface EnumerableBeliefState
    
    Returns:
    
    a List of EnumerableBeliefState.StateBelief objects specifying the enumerated probability mass function.
  - numStates
```
public int numStates()
```
    Returns the size of the observed underlying MDP state space.
    
    Returns:
    
    the size of the observed underlying MDP state space.
  - stateForId
```
public State stateForId(int id)
```
    Returns the corresponding MDP state for the provided unique identifier.
    
    Parameters:
    
    id - the MDP state identifier
    
    Returns:
    
    the corresponding MDP state, defined by a State, for the provided unique identifier.
  - setBelief
```
public void setBelief(State s,
                      double b)
```
    Sets the probability mass (belief) associated with the underlying MDP state. If this object has not yet assigned a unique identifier to the provided MDP state, then it will first create one. Note that using this method will not ensure that the total probability mass across this belief state sums to 1, so other changes will have to be specified manually.
    
    Parameters:
    
    s - the underlying MDP state defined as a State
    
    b - the probability mass to assigned to the underlying MDP state.
  - setBelief
```
public void setBelief(int stateId,
                      double b)
```
    Sets the probability mass (belief) associated with the underlying MDP state. Note that using this method will not ensure that the total probability mass across this belief state sums to 1, so other changes will have to be specified manually.
    
    Parameters:
    
    stateId - the unique numeric identifier of the underlying MDP state defined.
    
    b - the probability mass to assigned to the underlying MDP state.
  - setBeliefVector
```
public void setBeliefVector(double[] b)
```
    Sets this belief state to the provided. Dense belief vector. If the belief vector dimensionality does not match this objects dimensionality then a runtime exception will be thrown.
    
    Specified by:
    
    setBeliefVector in interface DenseBeliefVector
    
    Parameters:
    
    b - the belief vector to set this belief state to.
  - beliefVector
```
public double[] beliefVector()
```
    Returns this belief state as a dense (non-sparse) belief vector.
    
    Specified by:
    
    beliefVector in interface DenseBeliefVector
    
    Returns:
    
    a double array specifying this belief state as a dense (non-sparse) belief vector.
  - getStateSpace
```
public java.util.List<State> getStateSpace()
```
    Returns the set of underlying MDP states this belief vector spans.
    
    Returns:
    
    the set of underlying MDP states this belief vector spans.
  - zeroOutBeliefVector
```
public void zeroOutBeliefVector()
```
    Sets this belief state to have zero probability mass for all underlying MDP states.
  - initializeBeliefsUniformly
```
public void initializeBeliefsUniformly()
```
    Initializes this belief state to a uniform distribution
  - initializeAllBeliefValuesTo
```
public void initializeAllBeliefValuesTo(double initialValue)
```
    Initializes the probability mass of all underlying MDP states to the specified value. Note that this will not enforce summing to one, so you will have to manually modify the value of other states if initialValue is not 1/n where n is the number of underlying MDP states.
    
    Parameters:
    
    initialValue - the probability mass to assign to each state.
  - set
```
public MutableState set(java.lang.Object variableKey,
                        java.lang.Object value)
```
    Description copied from interface: MutableState
    
    Sets the value for the given variable key.
    
    Specified by:
    
    set in interface MutableState
    
    Parameters:
    
    variableKey - the key identifier for the variable value to change
    
    value - the variable value to which the variable should be set.
    
    Returns:
    
    this object to support method chaining
  - variableKeys
```
public java.util.List<java.lang.Object> variableKeys()
```
    Description copied from interface: State
    
    Returns the list of state variable keys.
    
    Specified by:
    
    variableKeys in interface State
    
    Returns:
    
    the list of state variable keys.
  - get
```
public java.lang.Object get(java.lang.Object variableKey)
```
    Description copied from interface: State
    
    Returns the value for the given variable key. Changes to the returned value are not guaranteed to modify the state.
    
    Specified by:
    
    get in interface State
    
    Parameters:
    
    variableKey - the variable key
    
    Returns:
    
    the value for the given variable key
  - copy
```
public State copy()
```
    Description copied from interface: State
    
    Returns a copy of this state suitable for creating state transitions. This copy may be a shallow copy or deep copy and is domain specific. The State implementation may indicate its copy level with the DeepCopyState or ShallowCopyState annotations. If it is a shallow copy, you should not *directly* modify any fields of a copied state without copying the fields first, or it could contaminate the state from which the copy was made. Alternatively, use the MutableState.set(Object, Object) method to modify ShallowCopyState copied states, which for ShallowCopyState instances should perform a safe copy-on-write operation.
    
    Specified by:
    
    copy in interface State
    
    Returns:
    
    a copy of this state.
  - s
```
public State s()
```
    Description copied from interface: HashableState
    
    Returns the underlying source state that is hashed.
    
    Specified by:
    
    s in interface HashableState
    
    Returns:
    
    The underlying source State that this object hashes and evaluates.
  - hashCode
```
public int hashCode()
```
    Overrides:
    
    hashCode in class java.lang.Object
  - equals
```
public boolean equals(java.lang.Object obj)
```
    Overrides:
    
    equals in class java.lang.Object
  - toString
```
public java.lang.String toString()
```
    Overrides:
    
    toString in class java.lang.Object

Class TabularBeliefState

Nested Class Summary

Nested classes/interfaces inherited from interface burlap.mdp.singleagent.pomdp.beliefstate.EnumerableBeliefState

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

stateEnumerator

beliefValues

domain

Constructor Detail

TabularBeliefState

TabularBeliefState

TabularBeliefState

TabularBeliefState

Method Detail

getStateEnumerator

setStateEnumerator

getBeliefValues

setBeliefValues

getDomain

setDomain

belief

belief

sample

nonZeroBeliefs

numStates

stateForId

setBelief

setBelief

setBeliefVector

beliefVector

getStateSpace

zeroOutBeliefVector

initializeBeliefsUniformly

initializeAllBeliefValuesTo

set

variableKeys

get

copy

s

hashCode

equals

toString