[Serializable]
[Quality(QualityBand.Mature)]
[DataContract]
public class DistributionRefArray<T, DomainType> : DistributionArray<T, DomainType>, IArray<T>, IList<T>, ICollection<T>, CanSetAllElementsTo<T>, IReadOnlyList<T>, IReadOnlyCollection<T>, IEnumerable<T>, IEnumerable, SettableTo<T[]>, SettableTo<Array<T>>, ConvertibleToArray, IDistribution<DomainType[]>, IDistribution, ICloneable, Diffable, SettableToUniform, HasPoint<DomainType[]>, CanGetLogProb<DomainType[]>, Sampleable<DomainType[]>, IArrayFactory<T, DistributionRefArray<T, DomainType>>, SettableTo<DistributionRefArray<T, DomainType>>, SettableToProduct<DistributionRefArray<T, DomainType>>, SettableToProduct<DistributionRefArray<T, DomainType>, DistributionRefArray<T, DomainType>>, SettableToRatio<DistributionRefArray<T, DomainType>>, SettableToRatio<DistributionRefArray<T, DomainType>, DistributionRefArray<T, DomainType>>, SettableToPower<DistributionRefArray<T, DomainType>>, SettableToWeightedSum<DistributionRefArray<T, DomainType>>, CanGetLogAverageOf<DistributionRefArray<T, DomainType>>, CanGetLogAverageOfPower<DistributionRefArray<T, DomainType>>, CanGetAverageLog<DistributionRefArray<T, DomainType>> where T : class, ICloneable, SettableTo<T>, SettableToProduct<T>, SettableToRatio<T>, SettableToPower<T>, SettableToWeightedSum<T>, CanGetLogAverageOf<T>, CanGetLogAverageOfPower<T>, CanGetAverageLog<T>, IDistribution<DomainType>, Sampleable<DomainType>

Type Parameters

Name	Description
T	Distribution type of an element
DomainType	Domain type of an element

Remarks

This is an extension of DistributionArray that requires T to be a reference type. The SetTo and CopyTo methods are overriden to use cloning instead of assignment.

Constructors

DistributionRefArray()

Parameterless constructor needed for serialization

Declaration

protected DistributionRefArray()

DistributionRefArray(T, Int32)

Creates a new distribution array given a value and a length

Declaration

public DistributionRefArray(T value, int length)

Parameters

Type	Name	Description
T	value
Int32	length

DistributionRefArray(T[])

Creates a new distribution array given an array of distributions

Declaration

public DistributionRefArray(T[] array)

Parameters

Type	Name	Description
T[]	array

DistributionRefArray(Array<T>)

Copy constructor

Declaration

public DistributionRefArray(Array<T> that)

Parameters

Type	Name	Description
Array<T>	that

DistributionRefArray(Int32)

Creates a distribution array given a length

Declaration

public DistributionRefArray(int length)

Parameters

Type	Name	Description
Int32	length

DistributionRefArray(Int32, Func<Int32, T>)

Create a distribution struct array of a specified length and initial values.

Declaration

public DistributionRefArray(int length, Func<int, T> init)

Parameters

Type	Name	Description
Int32	length
Func<Int32, T>	init	Function that maps an index to a value.

Remarks

The references returned by init are not copied. They are placed directly into the array.

Methods

Clone()

Clones the array and the items in the array.

Declaration

public override object Clone()

Returns

Type	Description
Object

Overrides

Microsoft.ML.Probabilistic.Collections.Array<T>.Clone()

CopyTo(T[])

Set the parameters of array[i] to match the marginal distribution of element i, creating a new distribution if array[i] was null

Declaration

public override void CopyTo(T[] array)

Parameters

Type	Name	Description
T[]	array	Array to write into

Overrides

Microsoft.ML.Probabilistic.Collections.Array<T>.CopyTo(T[])

CopyTo(T[], Int32)

Set the parameters of array[i] to match the marginal distribution of element i, creating a new distribution if array[i] was null, starting at a given index

Declaration

public override void CopyTo(T[] array, int arrayIndex)

Parameters

Type	Name	Description
T[]	array
Int32	arrayIndex	The index to start at

Overrides

Microsoft.ML.Probabilistic.Collections.ArrayBase<T>.CopyTo(T[], System.Int32)

CreateArray(Int32, Func<Int32, T>)

Declaration

public DistributionRefArray<T, DomainType> CreateArray(int length, Func<int, T> init)

Parameters

Type	Name	Description
Int32	length
Func<Int32, T>	init

Returns

Type	Description
DistributionRefArray<T, DomainType>

GetAverageLog(DistributionRefArray<T, DomainType>)

The expected logarithm of that distribution under this distribution.

Declaration

public double GetAverageLog(DistributionRefArray<T, DomainType> that)

Parameters

Type	Name	Description
DistributionRefArray<T, DomainType>	that	The distribution to take the logarithm of.

Returns

Type	Description
Double	`sum_x this.Evaluate(x)*Math.Log(that.Evaluate(x))`

Remarks

This is also known as the cross entropy. For a DistributionArray, this specializes to: sum_i sum_x this[i].Evaluate(x)*Math.Log(that[i].Evaluate(x)) = sum_i this[i].GetAverageLog(that[i])

GetLogAverageOf(DistributionRefArray<T, DomainType>)

The log-probability that two distributions would draw the same sample.

Declaration

public double GetLogAverageOf(DistributionRefArray<T, DomainType> that)

Parameters

Type	Name	Description
DistributionRefArray<T, DomainType>	that

Returns

Type	Description
Double	`Math.Log(sum_x this.Evaluate(x)*that.Evaluate(x))`

Remarks

This can be considered a type of inner product between distributions. Another name might be "LogAverage" to go with "GetAverageLog". For a DistributionArray, this specializes to: sum_i Math.Log(sum_x this[i].Evaluate(x)*that[i].Evaluate(x)) = sum_i this[i].GetLogAverageOf(that[i])

GetLogAverageOfPower(DistributionRefArray<T, DomainType>, Double)

Get the integral of this distribution times another distribution raised to a power.

Declaration

public double GetLogAverageOfPower(DistributionRefArray<T, DomainType> that, double power)

Parameters

Type	Name	Description
DistributionRefArray<T, DomainType>	that
Double	power

Returns

Type	Description
Double

InitializeTo(T)

Initialise all the values in this array to clones of the given value

Declaration

protected void InitializeTo(T value)

Parameters

Type	Name	Description
T	value

InitializeTo(T[])

Initialise the elements of this distribution array to clones of the given distributions

Declaration

protected void InitializeTo(T[] array)

Parameters

Type	Name	Description
T[]	array

Remarks

Given array and this array must be the same length

Sample(DomainType[])

Get a sample from the distribution

Declaration

public override DomainType[] Sample(DomainType[] result)

Parameters

Type	Name	Description
DomainType[]	result	Where to put the results

Returns

Type	Description
DomainType[]	A sample

Overrides

Microsoft.ML.Probabilistic.Distributions.DistributionArray<T, DomainType>.Sample(DomainType[])

SetAllElementsTo(T)

Set the parameters of this distribution so that all marginals equal the given distribution (by value)

Declaration

public override void SetAllElementsTo(T value)

Parameters

Type	Name	Description
T	value

Overrides

Microsoft.ML.Probabilistic.Collections.ArrayBase<T>.SetAllElementsTo(T)

SetItemsOf(T[])

Set the parameters of array[i] to match the marginal distribution of element i

Declaration

protected void SetItemsOf(T[] array)

Parameters

Type	Name	Description
T[]	array

SetItemsOf(T[], Int32)

Set the parameters of array[i] to match the marginal distribution of element i, starting at a given index

Declaration

protected void SetItemsOf(T[] array, int arrayIndex)

Parameters

Type	Name	Description
T[]	array
Int32	arrayIndex	The index to start at

SetTo(T[])

Set the parameters of this distribution so that the marginals match the given distributions (by value)

Declaration

public override void SetTo(T[] array)

Parameters

Type	Name	Description
T[]	array

Overrides

Microsoft.ML.Probabilistic.Collections.Array<T>.SetTo(T[])

Remarks

Given array and this array must be the same length.

SetTo(DistributionRefArray<T, DomainType>)

Set the parameters of this distribution to match those of the given distribution (by value)

Declaration

public void SetTo(DistributionRefArray<T, DomainType> that)

Parameters

Type	Name	Description
DistributionRefArray<T, DomainType>	that

SetToPower(DistributionRefArray<T, DomainType>, Double)

Set the parameters to represent the power of a source distribution to some exponent

Declaration

public void SetToPower(DistributionRefArray<T, DomainType> a, double exponent)

Parameters

Type	Name	Description
DistributionRefArray<T, DomainType>	a	The source distribution array
Double	exponent	The exponent

SetToProduct(DistributionRefArray<T, DomainType>, DistributionRefArray<T, DomainType>)

Set the parameters to represent the product of two distributions

Declaration

public void SetToProduct(DistributionRefArray<T, DomainType> a, DistributionRefArray<T, DomainType> b)

Parameters

Type	Name	Description
DistributionRefArray<T, DomainType>	a	The first distribution array
DistributionRefArray<T, DomainType>	b	The second distribution array

SetToRatio(DistributionRefArray<T, DomainType>, DistributionRefArray<T, DomainType>, Boolean)

Set the parameters to represent the ratio of two distributions

Declaration

public void SetToRatio(DistributionRefArray<T, DomainType> numerator, DistributionRefArray<T, DomainType> denominator, bool forceProper)

Parameters

Type	Name	Description
DistributionRefArray<T, DomainType>	numerator	The numerator distribution array
DistributionRefArray<T, DomainType>	denominator	The denominator distribution array
Boolean	forceProper	Argument passed to T.SetToRatio

SetToSum(Double, DistributionRefArray<T, DomainType>, Double, DistributionRefArray<T, DomainType>)

Set the parameters to match the moments of a mixture of two distributions

Declaration

public void SetToSum(double weight1, DistributionRefArray<T, DomainType> a, double weight2, DistributionRefArray<T, DomainType> b)

Parameters

Type	Name	Description
Double	weight1	The first weight
DistributionRefArray<T, DomainType>	a	The first distribution array
Double	weight2	The second weight
DistributionRefArray<T, DomainType>	b	The second distribution array