Package org.opennars.inference

Class BudgetFunctions

java.lang.Object

org.opennars.inference.UtilityFunctions

org.opennars.inference.BudgetFunctions

public final class BudgetFunctions
extends UtilityFunctions

Budget functions for resources allocation

Author:

Pei Wang, Patrick Hammer

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	BudgetFunctions.Activating

Constructor Summary

Constructors

Constructor	Description
BudgetFunctions()

Method Summary

Modifier and Type	Method	Description
static void	activate(BudgetValue receiver, BudgetValue amount, BudgetFunctions.Activating mode)	Activate a concept by an incoming TaskLink
static void	applyForgetting(BudgetValue budget, float forgetCycles, float relativeThreshold)	Decrease Priority after an item is used, called in Bag.
static BudgetValue	backward(TruthValue truth, DerivationContext nal)	Backward inference result and adjustment, stronger case
static BudgetValue	backwardWeak(TruthValue truth, DerivationContext nal)	Backward inference result and adjustment, weaker case
private static BudgetValue	budgetInference(float qual, float complexity, DerivationContext nal)	Common processing for all inference step
static BudgetValue	budgetTermLinkConcept(Concept c, BudgetValue taskBudget, TermLink termLink)
static BudgetValue	compoundBackward(Term content, DerivationContext nal)	Backward inference with CompoundTerm conclusion, stronger case
static BudgetValue	compoundBackwardWeak(Term content, DerivationContext nal)	Backward inference with CompoundTerm conclusion, weaker case
static BudgetValue	compoundForward(TruthValue truth, Term content, DerivationContext nal)	Forward inference with CompoundTerm conclusion
static float	conceptActivation(Memory mem, Term t)	Get the current activation level of a concept.
static BudgetValue	distributeAmongLinks(BudgetValue b, int n, Parameters narParameters)	Distribute the budget of a task among the links to it
static BudgetValue	forward(TruthValue truth, DerivationContext nal)	Forward inference result and adjustment
static void	merge(BudgetValue b, BudgetValue a)	Merge an item into another one in a bag, when the two are identical except in budget values
static float	rankBelief(Sentence judg, boolean rankTruthExpectation)	Determine the rank of a judgment by its quality and originality (stamp baseLength), called from Concept
(package private) static BudgetValue	revise(TruthValue tTruth, TruthValue bTruth, TruthValue truth, boolean feedbackToLinks, DerivationContext nal)	Evaluate the quality of a revision, then de-prioritize the premises
(package private) static BudgetValue	solutionEval(Sentence problem, Sentence solution, Task task, Memory memory)	Deprecated.
static float	truthToQuality(TruthValue t)	Determine the quality of a judgment by its truth value alone
static BudgetValue	update(Task task, TruthValue bTruth, Parameters narParameters)	Update a belief

Methods inherited from class java.lang.Object

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

Methods inherited from class org.opennars.inference.UtilityFunctions

and, aveAri, aveGeo, c2w, or, w2c

Constructor Detail

BudgetFunctions

public BudgetFunctions()

Method Detail

truthToQuality

public static final float truthToQuality(TruthValue t)

Determine the quality of a judgment by its truth value alone

Mainly decided by confidence, though binary judgment is also preferred

Parameters:

t - The truth value of a judgment

Returns:

The quality of the judgment, according to truth value only

rankBelief

public static final float rankBelief(Sentence judg,
                                     boolean rankTruthExpectation)

Determine the rank of a judgment by its quality and originality (stamp baseLength), called from Concept

Parameters:

judg - The judgment to be ranked

Returns:

The rank of the judgment, according to truth value only

revise

static BudgetValue revise(TruthValue tTruth,
                          TruthValue bTruth,
                          TruthValue truth,
                          boolean feedbackToLinks,
                          DerivationContext nal)

Evaluate the quality of a revision, then de-prioritize the premises

Parameters:

tTruth - The truth value of the judgment in the task

bTruth - The truth value of the belief

truth - The truth value of the conclusion of revision

Returns:

The budget for the new task

update

public static BudgetValue update(Task task,
                                 TruthValue bTruth,
                                 Parameters narParameters)

Update a belief

Parameters:

task - The task containing new belief

bTruth - Truth value of the previous belief

Returns:

Budget value of the updating task

distributeAmongLinks

public static BudgetValue distributeAmongLinks(BudgetValue b,
                                               int n,
                                               Parameters narParameters)

Distribute the budget of a task among the links to it

Parameters:

b - The original budget

n - Number of links

Returns:

Budget value for each link

activate

public static void activate(BudgetValue receiver,
                            BudgetValue amount,
                            BudgetFunctions.Activating mode)

Activate a concept by an incoming TaskLink

Parameters:

receiver - The budget receiving the activation

amount - The budget for the new item

applyForgetting

public static void applyForgetting(BudgetValue budget,
                                   float forgetCycles,
                                   float relativeThreshold)

Decrease Priority after an item is used, called in Bag. After a constant time, p should become d*p. Since in this period, the item is accessed c*p times, each time p-q should multiple d^(1/(c*p)). The intuitive meaning of the parameter "forgetRate" is: after this number of times of access, priority 1 will become d, it is a system parameter adjustable in run time.

Parameters:

budget - The previous budget value

forgetCycles - The budget for the new item

relativeThreshold - The relative threshold of the bag

merge

public static void merge(BudgetValue b,
                         BudgetValue a)

Merge an item into another one in a bag, when the two are identical except in budget values

Parameters:

b - The budget baseValue to be modified

a - The budget adjustValue doing the adjusting

forward

public static BudgetValue forward(TruthValue truth,
                                  DerivationContext nal)

Forward inference result and adjustment

Parameters:

truth - The truth value of the conclusion

Returns:

The budget value of the conclusion

backward

public static BudgetValue backward(TruthValue truth,
                                   DerivationContext nal)

Backward inference result and adjustment, stronger case

Parameters:

truth - The truth value of the belief deriving the conclusion

nal - Reference to the memory

Returns:

The budget value of the conclusion

backwardWeak

public static BudgetValue backwardWeak(TruthValue truth,
                                       DerivationContext nal)

Backward inference result and adjustment, weaker case

Parameters:

truth - The truth value of the belief deriving the conclusion

nal - Reference to the memory

Returns:

The budget value of the conclusion

compoundForward

public static BudgetValue compoundForward(TruthValue truth,
                                          Term content,
                                          DerivationContext nal)

Forward inference with CompoundTerm conclusion

Parameters:

truth - The truth value of the conclusion

content - The content of the conclusion

nal - Reference to the memory

Returns:

The budget of the conclusion

compoundBackward

public static BudgetValue compoundBackward(Term content,
                                           DerivationContext nal)

Backward inference with CompoundTerm conclusion, stronger case

Parameters:

content - The content of the conclusion

nal - Reference to the memory

Returns:

The budget of the conclusion

compoundBackwardWeak

public static BudgetValue compoundBackwardWeak(Term content,
                                               DerivationContext nal)

Backward inference with CompoundTerm conclusion, weaker case

Parameters:

content - The content of the conclusion

nal - Reference to the memory

Returns:

The budget of the conclusion

conceptActivation

public static float conceptActivation(Memory mem,
                                      Term t)

Get the current activation level of a concept.

Parameters:

t - The Term naming a concept

Returns:

the priority value of the concept

budgetInference

private static BudgetValue budgetInference(float qual,
                                           float complexity,
                                           DerivationContext nal)

Common processing for all inference step

Parameters:

qual - Quality of the inference

complexity - Syntactic complexity of the conclusion

nal - Reference to the memory

Returns:

Budget of the conclusion task

solutionEval

@Deprecated
static BudgetValue solutionEval(Sentence problem,
                                Sentence solution,
                                Task task,
                                Memory memory)

Deprecated.

budgetTermLinkConcept

public static BudgetValue budgetTermLinkConcept(Concept c,
                                                BudgetValue taskBudget,
                                                TermLink termLink)