Package com.bayesserver

Class NodeDistributions

java.lang.Object

java.util.AbstractMap<NodeDistributionKey,Distribution>

com.bayesserver.NodeDistributions

All Implemented Interfaces:

Map<NodeDistributionKey,Distribution>

public final class NodeDistributions
extends AbstractMap<NodeDistributionKey,Distribution>

Represents the distributions assigned to a Node. Temporal nodes and noisy nodes may require more than one distribution to be fully specified. In a Dynamic Bayesian Network (DBN) a node may require more than one distribution to be specified. This occurs when a temporal node has incoming links of order greater than zero. I.e. Has links from past time slices. For example, if a temporal node has an incoming link of order 1, then it will require a distribution at time t=0, and an additional distribution at t=1. This is because at time t=0 there is no previous time slice, but at time t=1 there is. For times greater than 1, in this example the distribution specified at time t=1 is still valid. However, if a new incoming link of order 12 was added, then an additional distribution would need to be specified at time t=12, valid for times t>=12.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	NodeDistributions.DistributionOrder	Identifies a distribution and its temporal order.

Nested classes/interfaces inherited from class java.util.AbstractMap

AbstractMap.SimpleEntry<K extends Object,V extends Object>, AbstractMap.SimpleImmutableEntry<K extends Object,V extends Object>

Nested classes/interfaces inherited from interface java.util.Map

Map.Entry<K extends Object,V extends Object>

Method Summary

Modifier and Type	Method	Description
boolean	canUpdate(NodeDistributionKey key)	Determines whether the distribution at the specified temporal order can be updated.
boolean	canUpdate(NodeDistributionKey key, NodeDistributionKind kind)	Determines whether the distribution at the specified temporal order can be updated.
Set<Map.Entry<NodeDistributionKey,Distribution>>	entrySet()
Distribution	findForTime(int time)	Finds the temporal distribution that is suitable for the time specified.
Distribution	findForTime(int time, NodeDistributionKind kind)	Finds the temporal distribution that is suitable for the time specified.
NodeDistributions.DistributionOrder	findForTimeWithOrder(int time)	Finds the temporal distribution that is suitable for the time specified.
NodeDistributions.DistributionOrder	findForTimeWithOrder(int time, NodeDistributionKind kind)	Finds the temporal distribution that is suitable for the time specified.
Distribution	get(int temporalOrder)	Gets a distribution at a particular temporal order.
Distribution	get(NodeDistributionKey key)	Gets a distribution with particular properties, such as temporal order.
Distribution	get(NodeDistributionKey key, NodeDistributionKind kind)	Gets a distribution with particular properties, such as temporal order.
Distribution	get(NodeDistributionKind kind)	Gets a particular kind of distribution on the node.
NodeDistributionExpressions	getExpressions()	Gets any expressions associated with a node, that are used to generate distributions.
Collection<NodeDistributionKey>	getKeys()	Gets the collection of node distribution keys that require distributions.
int	getMaxTemporalOrder()	Gets the current maximum temporal order.
Node	getNode()	Gets the node that this instance belongs to.
void	set(int temporalOrder, Distribution value)	Sets a distribution at a particular temporal order.
void	set(NodeDistributionKey key, Distribution value)	Sets a distribution with particular properties, such as temporal order.
void	set(NodeDistributionKey key, NodeDistributionKind kind, Distribution value)	Sets a distribution with particular properties, such as temporal order.
void	set(NodeDistributionKind kind, Distribution value)	Sets a particular kind of distribution on the node.
int	size()	Gets the number of distributions in the container.
void	validateDistribution(Distribution value, NodeDistributionKey key)	Checks that a distribution is correctly specified for a particular temporal order.
void	validateDistribution(Distribution value, NodeDistributionKey key, NodeDistributionKind kind)	Checks that a distribution is correctly specified for a particular temporal order.

Methods inherited from class java.util.AbstractMap

clear, clone, containsKey, containsValue, equals, get, hashCode, isEmpty, keySet, put, putAll, remove, toString, values

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface java.util.Map

compute, computeIfAbsent, computeIfPresent, forEach, getOrDefault, merge, putIfAbsent, remove, replace, replace, replaceAll

Method Detail

getExpressions

public NodeDistributionExpressions getExpressions()

Gets any expressions associated with a node, that are used to generate distributions.

findForTimeWithOrder

public NodeDistributions.DistributionOrder findForTimeWithOrder(int time)

Finds the temporal distribution that is suitable for the time specified.

Parameters:

time - The time.

Returns:

The distribution and order that is appropriate for the given time. Can return a null distribution, if the appropriate distribution has not yet been assigned to the node.

Throws:

IllegalStateException - Raised when an appropriate distribution could not be found.

findForTime

public Distribution findForTime(int time,
                                NodeDistributionKind kind)

Finds the temporal distribution that is suitable for the time specified.

Parameters:

time - The time.

kind - The kind of distribution to retrieve.

Returns:

The distribution and order that is appropriate for the given time. Can return a null distribution, if the appropriate distribution has not yet been assigned to the node.

Throws:

IllegalStateException - Raised when an appropriate distribution could not be found.

findForTime

public Distribution findForTime(int time)

Finds the temporal distribution that is suitable for the time specified.

Parameters:

time - The time.

Returns:

The distribution that is appropriate for the given time. Can return a null distribution, if the appropriate distribution has not yet been assigned to the node.

Throws:

IllegalStateException - Raised when an appropriate distribution could not be found.

findForTimeWithOrder

public NodeDistributions.DistributionOrder findForTimeWithOrder(int time,
                                                                NodeDistributionKind kind)

Finds the temporal distribution that is suitable for the time specified.

Parameters:

time - The time.

kind - The kind of distribution to retrieve.

Returns:

The distribution that is appropriate for the given time. Can return a null distribution, if the appropriate distribution has not yet been assigned to the node.

Throws:

IllegalStateException - Raised when an appropriate distribution could not be found.

getNode

public Node getNode()

Gets the node that this instance belongs to.

getKeys

public Collection<NodeDistributionKey> getKeys()

Gets the collection of node distribution keys that require distributions.

getMaxTemporalOrder

public int getMaxTemporalOrder()

Gets the current maximum temporal order.

canUpdate

public boolean canUpdate(NodeDistributionKey key)

Determines whether the distribution at the specified temporal order can be updated.

Parameters:

key - Properties identifying the distribution to check, such as temporal order/related node.

Returns:

true if the distribution can be updated, false otherwise.

canUpdate

public boolean canUpdate(NodeDistributionKey key,
                         NodeDistributionKind kind)

Determines whether the distribution at the specified temporal order can be updated.

Parameters:

key - Properties identifying the distribution to check, such as temporal order/related node.

kind - The kind of distribution to check.

Returns:

true if the distribution can be updated, false otherwise.

validateDistribution

public void validateDistribution(Distribution value,
                                 NodeDistributionKey key)

Checks that a distribution is correctly specified for a particular temporal order.

Parameters:

value - The distribution to test.

key - The properties that identify a particular distribution such as temporal order/related node.

validateDistribution

public void validateDistribution(Distribution value,
                                 NodeDistributionKey key,
                                 NodeDistributionKind kind)

Checks that a distribution is correctly specified for a particular temporal order.

Parameters:

value - The distribution to test.

key - The properties that identify a particular distribution such as temporal order/related node.

kind - The kind of distribution to validate.

get

public Distribution get(int temporalOrder)

Gets a distribution at a particular temporal order. When specifying temporal distributions, variables which belong to temporal nodes must have times associated. Each time must be specified relative to the current point in time which is defined as zero. E.g. to specify a distribution at time>=1 we would include variables at time -1 and 0.

Parameters:

temporalOrder - The required temporal order.

Returns:

The requested distribution, which can be null if the node does not support the requested temporal order, or if a distribution has not yet been assigned to that order.

Throws:

IllegalArgumentException - [temporalOrder] must be non negative.

set

public void set(int temporalOrder,
                Distribution value)

Sets a distribution at a particular temporal order. When specifying temporal distributions, variables which belong to temporal nodes must have times associated. Each time must be specified relative to the current point in time which is defined as zero. E.g. to specify a distribution at time>=1 we would include variables at time -1 and 0.

Parameters:

temporalOrder - The required temporal order.

Throws:

IllegalArgumentException - [temporalOrder] must be non negative.

get

public Distribution get(NodeDistributionKey key)

Gets a distribution with particular properties, such as temporal order.

When specifying temporal distributions, variables which belong to temporal nodes must have times associated. Each time must be specified relative to the current point in time which is defined as zero. E.g. to specify a distribution at time>=1 we would include variables at time -1 and 0.

For noisy nodes, multiple distributions are required, one for each parent and a leak distribution.

Parameters:

key - The properties of the required distribution, such as temporal order.

Returns:

The requested distribution, which can be null if the node does not support the requested temporal order, or if a distribution has not yet been assigned to that order.

Throws:

IllegalArgumentException - Temporal order must be non negative.

set

public void set(NodeDistributionKey key,
                Distribution value)

Sets a distribution with particular properties, such as temporal order.

When specifying temporal distributions, variables which belong to temporal nodes must have times associated. Each time must be specified relative to the current point in time which is defined as zero. E.g. to specify a distribution at time>=1 we would include variables at time -1 and 0.

For noisy nodes, multiple distributions are required, one for each parent and a leak distribution.

Parameters:

key - The properties of the required distribution, such as temporal order.

Throws:

IllegalArgumentException - Temporal order must be non negative.

get

public Distribution get(NodeDistributionKind kind)

Gets a particular kind of distribution on the node.

For temporal or noisy nodes, use the overload which accepts both a key and kind.

set

public void set(NodeDistributionKind kind,
                Distribution value)

Sets a particular kind of distribution on the node.

For temporal or noisy nodes, use the overload which accepts both a key and kind.

get

public Distribution get(NodeDistributionKey key,
                        NodeDistributionKind kind)

Gets a distribution with particular properties, such as temporal order.

When specifying temporal distributions, variables which belong to temporal nodes must have times associated. Each time must be specified relative to the current point in time which is defined as zero. E.g. to specify a distribution at time>=1 we would include variables at time -1 and 0.

For noisy nodes, multiple distributions are required, one for each parent and a leak distribution.

Parameters:

key - The properties of the required distribution, such as temporal order.

kind - The kind of distribution we are getting or setting. This allows setting other distribution types than Probability, such as Experience

Returns:

The requested distribution, which can be null if the node does not support the requested temporal order, or if a distribution has not yet been assigned to that order.

Throws:

IllegalArgumentException - Temporal order must be non negative.

set

public void set(NodeDistributionKey key,
                NodeDistributionKind kind,
                Distribution value)

Sets a distribution with particular properties, such as temporal order.

When specifying temporal distributions, variables which belong to temporal nodes must have times associated. Each time must be specified relative to the current point in time which is defined as zero. E.g. to specify a distribution at time>=1 we would include variables at time -1 and 0.

For noisy nodes, multiple distributions are required, one for each parent and a leak distribution.

Parameters:

key - The properties of the required distribution, such as temporal order.

kind - The kind of distribution we are getting or setting. This allows setting other distribution types than Probability, such as Experience

Throws:

IllegalArgumentException - Temporal order must be non negative.

size

public int size()

Gets the number of distributions in the container.

Specified by:

size in interface Map<NodeDistributionKey,Distribution>

Overrides:

size in class AbstractMap<NodeDistributionKey,Distribution>

entrySet

public Set<Map.Entry<NodeDistributionKey,Distribution>> entrySet()

Specified by:

entrySet in interface Map<NodeDistributionKey,Distribution>

Specified by:

entrySet in class AbstractMap<NodeDistributionKey,Distribution>