ProbabilityTable

java.lang.Object
- aima.core.probability.util.ProbabilityTable

All Implemented Interfaces:

CategoricalDistribution, Factor, ProbabilityDistribution, ProbabilityMass
```
public class ProbabilityTable
extends java.lang.Object
implements CategoricalDistribution, Factor
```
A Utility Class for associating values with a set of finite Random Variables. This is also the default implementation of the CategoricalDistribution and Factor interfaces (as they are essentially dependent on the same underlying data structures).

Author:

Ciaran O'Reilly

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static interface`	`ProbabilityTable.Iterator` Interface to be implemented by an object/algorithm that wishes to iterate over the possible assignments for the random variables comprising this table.

Constructor Summary

Constructors
Constructor and Description
`ProbabilityTable(java.util.Collection<RandomVariable> vars)`
`ProbabilityTable(double[] vals, RandomVariable... vars)`
`ProbabilityTable(RandomVariable... vars)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`boolean`	`contains(RandomVariable rv)`
`CategoricalDistribution`	`divideBy(CategoricalDistribution divisor)` Divide the dividend (this) CategoricalDistribution by the divisor to create a new CategoricalDistribution representing the quotient.
`ProbabilityTable`	`divideBy(ProbabilityTable divisor)`
`java.util.Set<RandomVariable>`	`getArgumentVariables()`
`java.util.Set<RandomVariable>`	`getFor()`
`int`	`getIndex(java.lang.Object... assignments)` Retrieve the index into the CategoricalDistribution for the provided set of values for the random variables comprising the Distribution.
`double`	`getSum()`
`double`	`getValue(AssignmentProposition... assignments)` Get the value for the provided set of AssignmentPropositions for the random variables comprising the Distribution (size of each must equal and their random variables must match).
`double`	`getValue(java.lang.Object... assignments)` Get the value for the provided set of values for the random variables comprising the Distribution (ordering and size of each must equal and their domains must match).
`double[]`	`getValues()` Note: Do not modify the double[] returned by this method directly.
`void`	`iterateOver(CategoricalDistribution.Iterator cdi)` Iterate over all the possible value assignments for the Random Variables comprising this CategoricalDistribution.
`void`	`iterateOver(CategoricalDistribution.Iterator cdi, AssignmentProposition... fixedValues)` Iterate over all possible values assignments for the Random Variables comprising this CategoricalDistribution that are not in the fixed set of values.
`void`	`iterateOver(Factor.Iterator fi)` Iterate over all the possible value assignments for the Random Variables comprising this Factor.
`void`	`iterateOver(Factor.Iterator fi, AssignmentProposition... fixedValues)` Iterate over all possible values assignments for the Random Variables comprising this Factor that are not in the fixed set of values.
`void`	`iterateOverTable(ProbabilityTable.Iterator pti)` Iterate over all the possible value assignments for the Random Variables comprising this ProbabilityTable.
`void`	`iterateOverTable(ProbabilityTable.Iterator pti, AssignmentProposition... fixedValues)` Iterate over all possible values assignments for the Random Variables comprising this ProbabilityTable that are not in the fixed set of values.
`CategoricalDistribution`	`marginal(RandomVariable... vars)` Get the marginal probability for the provided variables from this Distribution creating a new Distribution of the remaining variables with their values updated with the summed out random variables. see: AIMA3e page 492.
`CategoricalDistribution`	`multiplyBy(CategoricalDistribution multiplier)` Multiplication of this Distribution by a given multiplier, creating a new Distribution representing the product of the two.
`CategoricalDistribution`	`multiplyByPOS(CategoricalDistribution multiplier, RandomVariable... prodVarOrder)` Multiplication - Product Order Specified (POS).
`ProbabilityTable`	`normalize()` Normalize the values comprising this distribution.
`Factor`	`pointwiseProduct(Factor multiplier)` Pointwise multiplication of this Factor by a given multiplier, creating a new Factor representing the product of the two. see: AIMA3e Figure 14.10 page 527. Note: Default Factor multiplication is not commutative.
`ProbabilityTable`	`pointwiseProduct(ProbabilityTable multiplier)`
`Factor`	`pointwiseProductPOS(Factor multiplier, RandomVariable... prodVarOrder)` Pointwise Multiplication - Product Order Specified (POS). see: AIMA3e Figure 14.10 page 527. Pointwise multiplication of this Factor by a given multiplier, creating a new Factor representing the product of the two.
`ProbabilityTable`	`pointwiseProductPOS(ProbabilityTable multiplier, RandomVariable... prodVarOrder)`
`void`	`setValue(int idx, double value)` Set the value at a specified index within the distribution.
`int`	`size()`
`ProbabilityTable`	`sumOut(RandomVariable... vars)` Sum out the provided variables from this Factor creating a new Factor of the remaining variables with their values updated with the summed out random variables. see: AIMA3e page 527.
`java.lang.String`	`toString()`

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

- Constructor Detail
  - ProbabilityTable
```
public ProbabilityTable(java.util.Collection<RandomVariable> vars)
```
  - ProbabilityTable
```
public ProbabilityTable(RandomVariable... vars)
```
  - ProbabilityTable
```
public ProbabilityTable(double[] vals,
                        RandomVariable... vars)
```
- Method Detail
  - size
```
public int size()
```
  - getFor
```
public java.util.Set<RandomVariable> getFor()
```
    Specified by:
    
    getFor in interface ProbabilityDistribution
    
    Returns:
    
    a consistent ordered Set (e.g. LinkedHashSet) of the random variables this probability distribution is for.
  - contains
```
public boolean contains(RandomVariable rv)
```
    Specified by:
    
    contains in interface Factor
    
    Specified by:
    
    contains in interface ProbabilityDistribution
    
    Parameters:
    
    rv - the Random Variable to be checked.
    
    Returns:
    
    true if this Distribution is for the passed in Random Variable, false otherwise.
  - getValue
```
public double getValue(java.lang.Object... assignments)
```
    Description copied from interface: ProbabilityDistribution
    
    Get the value for the provided set of values for the random variables comprising the Distribution (ordering and size of each must equal and their domains must match).
    
    Specified by:
    
    getValue in interface ProbabilityDistribution
    
    Parameters:
    
    assignments - the values for the random variables comprising the Distribution
    
    Returns:
    
    the value for the possible worlds associated with the assignments for the random variables comprising the Distribution.
  - getValue
```
public double getValue(AssignmentProposition... assignments)
```
    Description copied from interface: ProbabilityDistribution
    
    Get the value for the provided set of AssignmentPropositions for the random variables comprising the Distribution (size of each must equal and their random variables must match).
    
    Specified by:
    
    getValue in interface ProbabilityDistribution
    
    Parameters:
    
    assignments - the assignment propositions for the random variables comprising the Distribution
    
    Returns:
    
    the value for the possible worlds associated with the assignments for the random variables comprising the Distribution.
  - getValues
```
public double[] getValues()
```
    Description copied from interface: CategoricalDistribution
    
    Note: Do not modify the double[] returned by this method directly. Instead use setValue() as this method is intended to be for read only purposes.
    
    Specified by:
    
    getValues in interface CategoricalDistribution
    
    Specified by:
    
    getValues in interface Factor
    
    Returns:
    
    the double[] used to represent the CategoricalDistribution.
    
    See Also:
    
    CategoricalDistribution.setValue(int, double)
  - setValue
```
public void setValue(int idx,
                     double value)
```
    Description copied from interface: CategoricalDistribution
    
    Set the value at a specified index within the distribution.
    
    Specified by:
    
    setValue in interface CategoricalDistribution
  - getSum
```
public double getSum()
```
    Specified by:
    
    getSum in interface CategoricalDistribution
    
    Returns:
    
    the summation of all of the elements within the Distribution.
  - normalize
```
public ProbabilityTable normalize()
```
    Description copied from interface: CategoricalDistribution
    
    Normalize the values comprising this distribution.
    
    Specified by:
    
    normalize in interface CategoricalDistribution
    
    Returns:
    
    this instance with its values normalized.
  - getIndex
```
public int getIndex(java.lang.Object... assignments)
```
    Description copied from interface: CategoricalDistribution
    
    Retrieve the index into the CategoricalDistribution for the provided set of values for the random variables comprising the Distribution.
    
    Specified by:
    
    getIndex in interface CategoricalDistribution
    
    Parameters:
    
    assignments - an ordered set of values for the random variables comprising the Distribution (Note: the order must match the order of the random variables describing the distribution)
    
    Returns:
    
    the index within the Distribution for the values specified.
    
    See Also:
    
    CategoricalDistribution.getValues(), ProbabilityDistribution.getFor()
  - marginal
```
public CategoricalDistribution marginal(RandomVariable... vars)
```
    Description copied from interface: CategoricalDistribution
    
    Get the marginal probability for the provided variables from this Distribution creating a new Distribution of the remaining variables with their values updated with the summed out random variables.
    
    see: AIMA3e page 492.
    
    Specified by:
    
    marginal in interface CategoricalDistribution
    
    Parameters:
    
    vars - the random variables to marginalize/sum out.
    
    Returns:
    
    a new Distribution containing any remaining random variables not summed out and a new set of values updated with the summed out values.
  - divideBy
```
public CategoricalDistribution divideBy(CategoricalDistribution divisor)
```
    Description copied from interface: CategoricalDistribution
    
    Divide the dividend (this) CategoricalDistribution by the divisor to create a new CategoricalDistribution representing the quotient. The variables comprising the divisor distribution must be a subset of the dividend. However, ordering of variables does not matter as the quotient contains the same variables as the dividend and the internal implementation logic should handle iterating through the two distributions correctly, irrespective of the order of their variables.
    
    Specified by:
    
    divideBy in interface CategoricalDistribution
    
    Returns:
    
    a new Distribution representing the quotient of the dividend (this) divided by the divisor.
  - multiplyBy
```
public CategoricalDistribution multiplyBy(CategoricalDistribution multiplier)
```
    Description copied from interface: CategoricalDistribution
    
    Multiplication of this Distribution by a given multiplier, creating a new Distribution representing the product of the two. Note: Is equivalent to pointwise product calculation on factors.
    
    see: AIMA3e Figure 14.10 page 527.
    
    Note: Default Distribution multiplication is not commutative. The reason is because the order of the variables comprising a Distribution dictate the ordering of the values for that distribution. For example (the General case of Baye's rule, AIMA3e pg. 496), using this API method:
    
    P(Y | X) = (P(X | Y)P(Y))/P(X)
    
    is NOT true, due to multiplication of distributions not being commutative. However:
    
    P(Y | X) = (P(Y)P(X | Y))/P(X)
    
    is true, using this API.
    
    The default order of the variable of the Distribution returned is the order of the variables as they are seen, as read from the left to right term, for e.g.:
    
    P(Y)P(X | Y)
    
    would give a Distribution of the following form:
    Y, X
    
    i.e. an ordered union of the variables from the two distributions.
    To override the default order of the product use multiplyByPOS().
    
    Specified by:
    
    multiplyBy in interface CategoricalDistribution
    
    Returns:
    
    a new Distribution representing the product of this and the passed in multiplier. The order of the variables comprising the product distribution is the ordered union of the left term (this) and the right term (multiplier).
    
    See Also:
    
    CategoricalDistribution.multiplyByPOS(CategoricalDistribution, RandomVariable...)
  - multiplyByPOS
```
public CategoricalDistribution multiplyByPOS(CategoricalDistribution multiplier,
                                             RandomVariable... prodVarOrder)
```
    Description copied from interface: CategoricalDistribution
    
    Multiplication - Product Order Specified (POS). Note: Is equivalent to pointwise product calculation.
    
    see: AIMA3e Figure 14.10 page 527.
    
    Multiplication of this Distribution by a given multiplier, creating a new Distribution representing the product of the two. The order of the variables comprising the product will match those specified. For example (the General case of Baye's rule, AIMA3e pg. 496), using this API method:
    
    P(Y | X) = (P(X | Y)P(Y), [Y, X])/P(X)
    
    is true when the correct product order is specified.
    
    Specified by:
    
    multiplyByPOS in interface CategoricalDistribution
    
    prodVarOrder - the order the variables comprising the product are to be in.
    
    Returns:
    
    a new Distribution representing the product of this and the passed in multiplier. The order of the variables comprising the product distribution is the order specified.
    
    See Also:
    
    CategoricalDistribution.multiplyBy(CategoricalDistribution)
  - iterateOver
```
public void iterateOver(CategoricalDistribution.Iterator cdi)
```
    Description copied from interface: CategoricalDistribution
    
    Iterate over all the possible value assignments for the Random Variables comprising this CategoricalDistribution.
    
    Specified by:
    
    iterateOver in interface CategoricalDistribution
    
    Parameters:
    
    cdi - the CategoricalDistribution Iterator to iterate.
  - iterateOver
```
public void iterateOver(CategoricalDistribution.Iterator cdi,
                        AssignmentProposition... fixedValues)
```
    Description copied from interface: CategoricalDistribution
    
    Iterate over all possible values assignments for the Random Variables comprising this CategoricalDistribution that are not in the fixed set of values. This allows you to iterate over a subset of possible combinations.
    
    Specified by:
    
    iterateOver in interface CategoricalDistribution
    
    Parameters:
    
    cdi - the CategoricalDistribution Iterator to iterate
    
    fixedValues - Fixed values for a subset of the Random Variables comprising this CategoricalDistribution.
  - getArgumentVariables
```
public java.util.Set<RandomVariable> getArgumentVariables()
```
    Specified by:
    
    getArgumentVariables in interface Factor
    
    Returns:
    
    a consistent ordered Set (e.g. LinkedHashSet) of the argument variables for this Factor.
  - sumOut
```
public ProbabilityTable sumOut(RandomVariable... vars)
```
    Description copied from interface: Factor
    
    Sum out the provided variables from this Factor creating a new Factor of the remaining variables with their values updated with the summed out random variables.
    
    see: AIMA3e page 527.
    
    Specified by:
    
    sumOut in interface Factor
    
    Parameters:
    
    vars - the random variables to sum out.
    
    Returns:
    
    a new Factor containing any remaining random variables not summed out and a new set of values updated with the summed out values.
  - pointwiseProduct
```
public Factor pointwiseProduct(Factor multiplier)
```
    Description copied from interface: Factor
    
    Pointwise multiplication of this Factor by a given multiplier, creating a new Factor representing the product of the two.
    
    see: AIMA3e Figure 14.10 page 527.
    
    Note: Default Factor multiplication is not commutative. The reason is because the order of the variables comprising a Factor dictate the ordering of the values for that factor. The default order of the variables of the Factor returned is the order of the variables as they are seen, as read from the left to right term, for e.g.:
    
    f₁(Y)f₂(X, Y)
    
    would give a Factor of the following form:
    Y, X
    
    i.e. an ordered union of the variables from the two factors.
    To override the default order of the product use pointwiseProductPOS().
    
    Specified by:
    
    pointwiseProduct in interface Factor
    
    Returns:
    
    a new Factor representing the pointwise product of this and the passed in multiplier. The order of the variables comprising the product factor is the ordered union of the left term (this) and the right term (multiplier).
    
    See Also:
    
    Factor.pointwiseProductPOS(Factor, RandomVariable...)
  - pointwiseProductPOS
```
public Factor pointwiseProductPOS(Factor multiplier,
                                  RandomVariable... prodVarOrder)
```
    Description copied from interface: Factor
    
    Pointwise Multiplication - Product Order Specified (POS).
    
    see: AIMA3e Figure 14.10 page 527.
    
    Pointwise multiplication of this Factor by a given multiplier, creating a new Factor representing the product of the two. The order of the variables comprising the product will match those specified.
    
    Specified by:
    
    pointwiseProductPOS in interface Factor
    
    prodVarOrder - the order the variables comprising the product are to be in.
    
    Returns:
    
    a new Factor representing the pointwise product of this and the passed in multiplier. The order of the variables comprising the product distribution is the order specified.
    
    See Also:
    
    Factor.pointwiseProduct(Factor)
  - iterateOver
```
public void iterateOver(Factor.Iterator fi)
```
    Description copied from interface: Factor
    
    Iterate over all the possible value assignments for the Random Variables comprising this Factor.
    
    Specified by:
    
    iterateOver in interface Factor
    
    Parameters:
    
    fi - the Factor Iterator to iterate.
  - iterateOver
```
public void iterateOver(Factor.Iterator fi,
                        AssignmentProposition... fixedValues)
```
    Description copied from interface: Factor
    
    Iterate over all possible values assignments for the Random Variables comprising this Factor that are not in the fixed set of values. This allows you to iterate over a subset of possible combinations.
    
    Specified by:
    
    iterateOver in interface Factor
    
    Parameters:
    
    fi - the Factor Iterator to iterate
    
    fixedValues - Fixed values for a subset of the Random Variables comprising this Factor.
  - iterateOverTable
```
public void iterateOverTable(ProbabilityTable.Iterator pti)
```
    Iterate over all the possible value assignments for the Random Variables comprising this ProbabilityTable.
    
    Parameters:
    
    pti - the ProbabilityTable Iterator to iterate.
  - iterateOverTable
```
public void iterateOverTable(ProbabilityTable.Iterator pti,
                             AssignmentProposition... fixedValues)
```
    Iterate over all possible values assignments for the Random Variables comprising this ProbabilityTable that are not in the fixed set of values. This allows you to iterate over a subset of possible combinations.
    
    Parameters:
    
    pti - the ProbabilityTable Iterator to iterate
    
    fixedValues - Fixed values for a subset of the Random Variables comprising this Probability Table.
  - divideBy
```
public ProbabilityTable divideBy(ProbabilityTable divisor)
```
  - pointwiseProduct
```
public ProbabilityTable pointwiseProduct(ProbabilityTable multiplier)
```
  - pointwiseProductPOS
```
public ProbabilityTable pointwiseProductPOS(ProbabilityTable multiplier,
                                            RandomVariable... prodVarOrder)
```
  - toString
```
public java.lang.String toString()
```
    Overrides:
    
    toString in class java.lang.Object

Class ProbabilityTable

Nested Class Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

ProbabilityTable

ProbabilityTable

ProbabilityTable

Method Detail

size

getFor

contains

getValue

getValue

getValues

setValue

getSum

normalize

getIndex

marginal

divideBy

multiplyBy

multiplyByPOS

iterateOver

iterateOver

getArgumentVariables

sumOut

pointwiseProduct

pointwiseProductPOS

iterateOver

iterateOver

iterateOverTable

iterateOverTable

divideBy

pointwiseProduct

pointwiseProductPOS

toString