Struct ImmutableDiscreteChar

Represents a distribution over characters.

Implements
Inherited Members
Namespace: Microsoft.ML.Probabilistic.Distributions
Assembly: Microsoft.ML.Probabilistic.dll
Syntax
[Quality(QualityBand.Experimental)]
[Serializable]
public struct ImmutableDiscreteChar : IImmutableDistribution<char, ImmutableDiscreteChar>, IImmutableDistribution, ICloneable, Diffable, CanCreateUniform<ImmutableDiscreteChar>, CanCreatePointMass<char, ImmutableDiscreteChar>, CanGetLogProb<char>, CanCreatePartialUniform<ImmutableDiscreteChar>, CanGetMode<char>, CanGetLogAverageOf<ImmutableDiscreteChar>, CanGetLogAverageOfPower<ImmutableDiscreteChar>, CanGetAverageLog<ImmutableDiscreteChar>, CanEnumerateSupport<char>, CanComputeProduct<ImmutableDiscreteChar>, CanComputeProduct<ImmutableDiscreteChar, ImmutableDiscreteChar>, CanComputeRatio<ImmutableDiscreteChar>, CanComputeRatio<ImmutableDiscreteChar, ImmutableDiscreteChar>, CanComputePower<ImmutableDiscreteChar>, SummableExactly<ImmutableDiscreteChar>, SummableExactly<ImmutableDiscreteChar, ImmutableDiscreteChar>, Summable<ImmutableDiscreteChar, ImmutableDiscreteChar>, Sampleable<char>, ISerializable, IEquatable<ImmutableDiscreteChar>

Properties

IsDigit

Gets a value indicating whether this distribution equals the distribution created by Digit().

Declaration
public readonly bool IsDigit { get; }
Property Value
Type Description
Boolean

IsInitialized

Declaration
public readonly bool IsInitialized { get; }
Property Value
Type Description
Boolean

IsLetter

Gets a value indicating whether this distribution equals the distribution created by Letter().

Declaration
public readonly bool IsLetter { get; }
Property Value
Type Description
Boolean

IsLetterOrDigit

Gets a value indicating whether this distribution equals the distribution created by LetterOrDigit().

Declaration
public readonly bool IsLetterOrDigit { get; }
Property Value
Type Description
Boolean

IsLower

Gets a value indicating whether this distribution equals the distribution created by Lower().

Declaration
public readonly bool IsLower { get; }
Property Value
Type Description
Boolean

IsPointMass

Gets whether the distribution parameters represent a point mass.

Declaration
public readonly bool IsPointMass { get; }
Property Value
Type Description
Boolean

IsUpper

Gets a value indicating whether this distribution equals the distribution created by Upper().

Declaration
public readonly bool IsUpper { get; }
Property Value
Type Description
Boolean

IsWordChar

Gets a value indicating whether this distribution equals the distribution created by WordChar().

Declaration
public readonly bool IsWordChar { get; }
Property Value
Type Description
Boolean

Item[Char]

Gets the probability of a given character under this distribution.

Declaration
public readonly double this[char value] { get; }
Parameters
Type Name Description
Char value

The character.
Property Value
Type Description
Double

The probability of the character under this distribution.

Point

Gets the point mass represented by the distribution.

Declaration
public readonly char Point { get; }
Property Value
Type Description
Char

Ranges

Gets an array of character ranges with associated probabilities.

Declaration
public readonly ReadOnlyArray<ImmutableDiscreteChar.CharRange> Ranges { get; }
Property Value
Type Description
ReadOnlyArray<ImmutableDiscreteChar.CharRange>

An array of character ranges with associated probabilities.

Methods

Any()

Creates a uniform distribution over all characters.

Declaration
public static ImmutableDiscreteChar Any()
Returns
Type Description
ImmutableDiscreteChar

The created distribution.

AppendRegex(StringBuilder, Boolean)

Appends a regex expression that represents this character to the supplied string builder.

Declaration
public void AppendRegex(StringBuilder stringBuilder, bool useFriendlySymbols = false)
Parameters
Type Name Description
StringBuilder stringBuilder

The string builder to append to
Boolean useFriendlySymbols

Whether to use friendly symbols."

AppendToString(StringBuilder)

Declaration
public void AppendToString(StringBuilder stringBuilder)
Parameters
Type Name Description
StringBuilder stringBuilder

Clone()

Creates a copy of this distribution.

Declaration
public ImmutableDiscreteChar Clone()
Returns
Type Description
ImmutableDiscreteChar

The created copy.

Complement()

Creates a distribution which is uniform over all characters that have zero probability under this distribution i.e. that are not 'in' this distribution.

Declaration
public ImmutableDiscreteChar Complement()
Returns
Type Description
ImmutableDiscreteChar

The created distribution.
Remarks

This is useful for defining characters that are not in a particular distribution e.g. not a letter or not a word character.

Create(IEnumerable<ImmutableDiscreteChar.CharRange>)

Creates a distribution given a list of constant probability character ranges.

Declaration
[Construction(new string[]{"Ranges"})]
public static ImmutableDiscreteChar Create(IEnumerable<ImmutableDiscreteChar.CharRange> ranges)
Parameters
Type Name Description
IEnumerable<ImmutableDiscreteChar.CharRange> ranges

The constant-probability character ranges.
Returns
Type Description
ImmutableDiscreteChar

The created distribution.
Remarks

The probabilities do not need to be normalized. The character ranges do not need to be sorted.

CreatePartialUniform()

Creates a distribution uniform over the support of the current distribution.

Declaration
public ImmutableDiscreteChar CreatePartialUniform()
Returns
Type Description
ImmutableDiscreteChar

The created distribution.

CreatePointMass(Char)

Creates a point mass distribution.

Declaration
public ImmutableDiscreteChar CreatePointMass(char point)
Parameters
Type Name Description
Char point
Returns
Type Description
ImmutableDiscreteChar

The created distribution.

CreateUniform()

Creates a uniform distribution

Declaration
public ImmutableDiscreteChar CreateUniform()
Returns
Type Description
ImmutableDiscreteChar

The created distribution.

Digit()

Creates a uniform distribution over digits '0'..'9'.

Declaration
[Construction(UseWhen = "IsDigit")]
public static ImmutableDiscreteChar Digit()
Returns
Type Description
ImmutableDiscreteChar

The created distribution.

Divide(ImmutableDiscreteChar, Boolean)

Computes the product of the current instance and denominator.

Declaration
public ImmutableDiscreteChar Divide(ImmutableDiscreteChar denominator, bool forceProper = false)
Parameters
Type Name Description
ImmutableDiscreteChar denominator
Boolean forceProper

If true, the result is modified to have parameters in a safe range
Returns
Type Description
ImmutableDiscreteChar

EnumerateSupport()

Enumerates over the support of the distribution instance.

Declaration
public IEnumerable<char> EnumerateSupport()
Returns
Type Description
IEnumerable<Char>

The character values with non-zero mass.

Equals(ImmutableDiscreteChar)

Checks if that equals to this distribution (i.e. represents the same distribution over characters).

Declaration
public bool Equals(ImmutableDiscreteChar that)
Parameters
Type Name Description
ImmutableDiscreteChar that

The object to compare this distribution with.
Returns
Type Description
Boolean

true if this distribution is equal to that, false otherwise.

Equals(Object)

Checks if obj equals to this distribution (i.e. represents the same distribution over characters).

Declaration
public override bool Equals(object obj)
Parameters
Type Name Description
Object obj

The object to compare this distribution with.
Returns
Type Description
Boolean

true if this distribution is equal to obj, false otherwise.
Overrides

FromVector(PiecewiseVector)

Creates a point character from a vector of (unnormalized) character probabilities.

Declaration
public static ImmutableDiscreteChar FromVector(PiecewiseVector vector)
Parameters
Type Name Description
PiecewiseVector vector

The vector of unnormalized probabilities.
Returns
Type Description
ImmutableDiscreteChar

The created distribution.

FromVector(Vector)

Creates a point character from a vector of (unnormalized) character probabilities.

Declaration
public static ImmutableDiscreteChar FromVector(Vector vector)
Parameters
Type Name Description
Vector vector

The vector of unnormalized probabilities.
Returns
Type Description
ImmutableDiscreteChar

The created distribution.

GetAverageLog(ImmutableDiscreteChar)

The expected logarithm of that distribution under this distribution.

Declaration
public double GetAverageLog(ImmutableDiscreteChar distribution)
Parameters
Type Name Description
ImmutableDiscreteChar distribution
Returns
Type Description
Double

sum_x this.Evaluate(x)*Math.Log(that.Evaluate(x))
Remarks

This is also known as the cross entropy.

GetHashCode()

Gets the hash code of this distribution.

Declaration
public override int GetHashCode()
Returns
Type Description
Int32

The hash code.
Overrides

GetImpliedCharClasses(ImmutableDiscreteChar.CharClasses)

Declaration
public static ImmutableDiscreteChar.CharClasses GetImpliedCharClasses(ImmutableDiscreteChar.CharClasses charClass)
Parameters
Type Name Description
ImmutableDiscreteChar.CharClasses charClass
Returns
Type Description
ImmutableDiscreteChar.CharClasses

GetLogAverageOf(ImmutableDiscreteChar)

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

Declaration
public double GetLogAverageOf(ImmutableDiscreteChar distribution)
Parameters
Type Name Description
ImmutableDiscreteChar distribution
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.

GetLogAverageOfPower(ImmutableDiscreteChar, Double)

The log-integral of one distribution times another raised to a power.

Declaration
public double GetLogAverageOfPower(ImmutableDiscreteChar distribution, double power)
Parameters
Type Name Description
ImmutableDiscreteChar distribution
Double power

The exponent
Returns
Type Description
Double

Math.Log(sum_x this.Evaluate(x)*Math.Pow(that.Evaluate(x),power))
Remarks

This is not the same as GetLogAverageOf(that^power) because it includes the normalization constant of that.

GetLogProb(Char)

Evaluate the log of the density function at the specified domain value

Declaration
public double GetLogProb(char value)
Parameters
Type Name Description
Char value
Returns
Type Description
Double

The log density

GetMode()

Gets the mode of this distribution.

Declaration
public char GetMode()
Returns
Type Description
Char

The mode.

GetProbs()

Gets a vector of character probabilities under this distribution.

Declaration
public PiecewiseVector GetProbs()
Returns
Type Description
PiecewiseVector

A vector of character probabilities.

InRange(Char, Char)

Creates a uniform distribution over characters in a given range.

Declaration
public static ImmutableDiscreteChar InRange(char start, char end)
Parameters
Type Name Description
Char start

The start of the range (inclusive).
Char end

The end of the range (inclusive).
Returns
Type Description
ImmutableDiscreteChar

The created distribution.

InRanges(Char[])

Creates a distribution which is uniform over values in multiple ranges specified by pairs of start and end values. These pairs are specified as adjacent values in an array whose length must therefore be even.

Declaration
public static ImmutableDiscreteChar InRanges(params char[] startEndPairs)
Parameters
Type Name Description
Char[] startEndPairs

The array of range starts and ends.
Returns
Type Description
ImmutableDiscreteChar

The created distribution.

InRanges(IEnumerable<Char>)

Creates a distribution which is uniform over values in multiple ranges specified by pairs of start and end values. These pairs are specified as adjacent values in a sequence whose length must therefore be even.

Declaration
public static ImmutableDiscreteChar InRanges(IEnumerable<char> startEndPairs)
Parameters
Type Name Description
IEnumerable<Char> startEndPairs

The sequence of range starts and ends.
Returns
Type Description
ImmutableDiscreteChar

The created distribution.

IsPartialUniform()

Checks whether the distribution is uniform over its support.

Declaration
public bool IsPartialUniform()
Returns
Type Description
Boolean

true if the distribution is uniform over its support, false otherwise.

IsUniform()

Checks whether this distribution is a uniform distribution over all characters.

Declaration
public bool IsUniform()
Returns
Type Description
Boolean

true if this distribution is a uniform distribution over all possible characters, false otherwise.

Letter()

Creates a uniform distribution over letters.

Declaration
[Construction(UseWhen = "IsLetter")]
public static ImmutableDiscreteChar Letter()
Returns
Type Description
ImmutableDiscreteChar

The created distribution.

LetterOrDigit()

Creates a uniform distribution over letters and '0'..'9'.

Declaration
[Construction(UseWhen = "IsLetterOrDigit")]
public static ImmutableDiscreteChar LetterOrDigit()
Returns
Type Description
ImmutableDiscreteChar

The created distribution.

Lower()

Creates a uniform distribution over lowercase letters.

Declaration
[Construction(UseWhen = "IsLower")]
public static ImmutableDiscreteChar Lower()
Returns
Type Description
ImmutableDiscreteChar

The created distribution.

MaxDiff(Object)

Gets the maximum difference between the character probabilities under this distribution and a given one.

Declaration
public double MaxDiff(object distribution)
Parameters
Type Name Description
Object distribution

The distribution to compute the maximum probability difference with.
Returns
Type Description
Double

The computed maximum probability difference.

Multiply(ImmutableDiscreteChar)

Computes the product of the current instance and other.

Declaration
public ImmutableDiscreteChar Multiply(ImmutableDiscreteChar other)
Parameters
Type Name Description
ImmutableDiscreteChar other
Returns
Type Description
ImmutableDiscreteChar

The product.

NonWordChar()

Creates a uniform distribution over all characters except (letter, digit and '_').

Declaration
public static ImmutableDiscreteChar NonWordChar()
Returns
Type Description
ImmutableDiscreteChar

The created distribution.

OneOf(Char[])

Creates a distribution which is uniform over the specified set of characters.

Declaration
public static ImmutableDiscreteChar OneOf(params char[] chars)
Parameters
Type Name Description
Char[] chars

The characters.
Returns
Type Description
ImmutableDiscreteChar

The created distribution.

OneOf(IEnumerable<Char>)

Creates a distribution which is uniform over the specified set of characters.

Declaration
public static ImmutableDiscreteChar OneOf(IEnumerable<char> chars)
Parameters
Type Name Description
IEnumerable<Char> chars

The characters.
Returns
Type Description
ImmutableDiscreteChar

The created distribution.

PointMass(Char)

Creates a point mass character distribution.

Declaration
public static ImmutableDiscreteChar PointMass(char point)
Parameters
Type Name Description
Char point

The point.
Returns
Type Description
ImmutableDiscreteChar

The created distribution.

Pow(Double)

Computes the value of the current instance raised to a power.

Declaration
public ImmutableDiscreteChar Pow(double power)
Parameters
Type Name Description
Double power
Returns
Type Description
ImmutableDiscreteChar

Read(Func<Int32>, Func<Double>)

Reads a discrete character.

Declaration
public static ImmutableDiscreteChar Read(Func<int> readInt32, Func<double> readDouble)
Parameters
Type Name Description
Func<Int32> readInt32
Func<Double> readDouble
Returns
Type Description
ImmutableDiscreteChar

Sample()

Sample the distribution

Declaration
public char Sample()
Returns
Type Description
Char

The sample value

Sample(Char)

Draws a sample from the distribution.

Declaration
public char Sample(char result)
Parameters
Type Name Description
Char result

A pre-allocated storage for the sample (will be ignored).
Returns
Type Description
Char

The drawn sample.

Sum(Weight, ImmutableDiscreteChar, Weight)

Computes a weighted sum of the current and the given distributions

Declaration
public ImmutableDiscreteChar Sum(Weight weightThis, ImmutableDiscreteChar other, Weight weightOther)
Parameters
Type Name Description
Weight weightThis

The weight of the current distribution.
ImmutableDiscreteChar other

The given distribution.
Weight weightOther

The weight of the given distribution.
Returns
Type Description
ImmutableDiscreteChar

Sum(Double, ImmutableDiscreteChar, Double)

Computes a weighted sum of the current and the given distributions

Declaration
public ImmutableDiscreteChar Sum(double weightThis, ImmutableDiscreteChar other, double weightOther)
Parameters
Type Name Description
Double weightThis

The weight of the current distribution.
ImmutableDiscreteChar other

The given distribution.
Double weightOther

The weight of the given distribution.
Returns
Type Description
ImmutableDiscreteChar

ToLower(ImmutableDiscreteChar)

Declaration
public static ImmutableDiscreteChar ToLower(ImmutableDiscreteChar unnormalizedCharDist)
Parameters
Type Name Description
ImmutableDiscreteChar unnormalizedCharDist
Returns
Type Description
ImmutableDiscreteChar

ToString()

Gets a string that represents this distribution.

Declaration
public override string ToString()
Returns
Type Description
String

A string that represents this distribution.
Overrides

Uniform()

Creates a uniform distribution over characters.

Declaration
[Construction(UseWhen = "IsUniform")]
public static ImmutableDiscreteChar Uniform()
Returns
Type Description
ImmutableDiscreteChar

The created distribution.

UniformInRange(Char, Char)

Creates a uniform distribution over characters in a given range.

Declaration
public static ImmutableDiscreteChar UniformInRange(char start, char end)
Parameters
Type Name Description
Char start

The start of the range (inclusive).
Char end

The end of the range (inclusive).
Returns
Type Description
ImmutableDiscreteChar

The created distribution.

UniformInRanges(Char[])

Creates a distribution which is uniform over values in multiple ranges specified by pairs of start and end values. These pairs are specified as adjacent values in an array whose length must therefore be even.

Declaration
public static ImmutableDiscreteChar UniformInRanges(params char[] startEndPairs)
Parameters
Type Name Description
Char[] startEndPairs

The array of range starts and ends.
Returns
Type Description
ImmutableDiscreteChar

The created distribution.

UniformInRanges(IEnumerable<Char>)

Creates a distribution which is uniform over values in multiple ranges specified by pairs of start and end values. These pairs are specified as adjacent values in a sequence whose length must therefore be even.

Declaration
public static ImmutableDiscreteChar UniformInRanges(IEnumerable<char> startEndPairs)
Parameters
Type Name Description
IEnumerable<Char> startEndPairs

The sequence of range starts and ends.
Returns
Type Description
ImmutableDiscreteChar

The created distribution.

UniformOver(Char[])

Creates a distribution which is uniform over the specified set of characters.

Declaration
public static ImmutableDiscreteChar UniformOver(params char[] chars)
Parameters
Type Name Description
Char[] chars

The characters.
Returns
Type Description
ImmutableDiscreteChar

The created distribution.

UniformOver(IEnumerable<Char>)

Creates a distribution which is uniform over the specified set of characters.

Declaration
public static ImmutableDiscreteChar UniformOver(IEnumerable<char> chars)
Parameters
Type Name Description
IEnumerable<Char> chars

The characters.
Returns
Type Description
ImmutableDiscreteChar

The created distribution.

Upper()

Creates a uniform distribution over uppercase letters.

Declaration
[Construction(UseWhen = "IsUpper")]
public static ImmutableDiscreteChar Upper()
Returns
Type Description
ImmutableDiscreteChar

The created distribution.

Whitespace()

Creates a uniform distribution over whitespace characters ('\t'..'\r', ' ').

Declaration
public static ImmutableDiscreteChar Whitespace()
Returns
Type Description
ImmutableDiscreteChar

The created distribution.

WordChar()

Creates a uniform distribution over word characters (letter, digit and '_').

Declaration
[Construction(UseWhen = "IsWordChar")]
public static ImmutableDiscreteChar WordChar()
Returns
Type Description
ImmutableDiscreteChar

The created distribution.

Write(Action<Int32>, Action<Double>)

Writes a discrete character.

Declaration
public void Write(Action<int> writeInt32, Action<double> writeDouble)
Parameters
Type Name Description
Action<Int32> writeInt32
Action<Double> writeDouble

Explicit Interface Implementations

ICloneable.Clone()

Creates a copy of this distribution.

Declaration
object ICloneable.Clone()
Returns
Type Description
Object

The created copy.

ISerializable.GetObjectData(SerializationInfo, StreamingContext)

Declaration
void ISerializable.GetObjectData(SerializationInfo info, StreamingContext context)
Parameters
Type Name Description
SerializationInfo info
StreamingContext context

Implements