io.improbable.keanu.vertices.intgr.probabilistic

Class FuzzyCastToIntegerVertex

java.lang.Object

io.improbable.keanu.vertices.Vertex<java.lang.Integer>

io.improbable.keanu.vertices.intgr.IntegerVertex

io.improbable.keanu.vertices.intgr.probabilistic.ProbabilisticInteger

io.improbable.keanu.vertices.intgr.probabilistic.FuzzyCastToIntegerVertex

All Implemented Interfaces:

Identifiable, io.improbable.keanu.kotlin.IntegerOperators<IntegerVertex>, io.improbable.keanu.kotlin.Operators<IntegerVertex>

public class FuzzyCastToIntegerVertex
extends ProbabilisticInteger

Field Summary

Fields inherited from class io.improbable.keanu.vertices.Vertex

idGenerator

Constructor Summary

Constructors

Constructor and Description
FuzzyCastToIntegerVertex(DoubleVertex input, double fuzzinessSigma, int min, int max, java.util.Random random)
FuzzyCastToIntegerVertex(DoubleVertex input, DoubleVertex fuzzinessSigma, Vertex<java.lang.Integer> min, Vertex<java.lang.Integer> max, java.util.Random random) Takes a double and casts it to an integer with a user definable level of fuzziness over the value cast to.

Method Summary

Modifier and Type	Method and Description
java.util.Map<java.lang.String,java.lang.Double>	dDensityAtValue() This returns the derivative of the density function with respect to any dependent vertices.
double	density(java.lang.Integer value) This is the value of the probability density at the supplied value.
java.util.Map<java.lang.String,java.lang.Double>	dlnDensityAtValue() This is the same as dDensityAtValue except for the log of the density.
java.lang.Integer	sample()

Methods inherited from class io.improbable.keanu.vertices.intgr.probabilistic.ProbabilisticInteger

isProbabilistic, lazyEval, updateValue

Methods inherited from class io.improbable.keanu.vertices.intgr.IntegerVertex

abs, div, div, divideBy, divideBy, divideBy, lambda, minus, minus, minus, multiply, multiply, multiply, plus, plus, plus, times, times, unaryMinus

Methods inherited from class io.improbable.keanu.vertices.Vertex

addChild, addParent, addParents, densityAtValue, equals, getChildren, getConnectedGraph, getId, getParents, getValue, hashCode, isObserved, logDensity, logDensityAtValue, observe, observeOwnValue, setAndCascade, setParents, setParents, setValue, unobserve, updateChildren

Methods inherited from class java.lang.Object

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

Constructor Detail

FuzzyCastToIntegerVertex

public FuzzyCastToIntegerVertex(DoubleVertex input,
                                DoubleVertex fuzzinessSigma,
                                Vertex<java.lang.Integer> min,
                                Vertex<java.lang.Integer> max,
                                java.util.Random random)

Takes a double and casts it to an integer with a user definable level of fuzziness over the value cast to. The range of potential integer values cast to is specified with a min and max (inclusive). The probability of casting to a given integer is represented as a Gaussian distribution centred on the input value, with a use specifiable sigma. E.n., a sigma value of 0 will guarantee casting ot the nearest integer value with half up rounding.

Parameters:

input -

fuzzinessSigma - fuzziness is represented as a Gaussian distribution with mu of the input value and this sigma.

min - inclusive

max - inclusive

random -

FuzzyCastToIntegerVertex

public FuzzyCastToIntegerVertex(DoubleVertex input,
                                double fuzzinessSigma,
                                int min,
                                int max,
                                java.util.Random random)

Method Detail

density

public double density(java.lang.Integer value)

Description copied from class: Vertex

This is the value of the probability density at the supplied value.

Specified by:

density in class Vertex<java.lang.Integer>

Parameters:

value - The supplied value.

Returns:

The probability.

dDensityAtValue

public java.util.Map<java.lang.String,java.lang.Double> dDensityAtValue()

Description copied from class: Vertex

This returns the derivative of the density function with respect to any dependent vertices.

Specified by:

dDensityAtValue in class Vertex<java.lang.Integer>

Returns:

a Map containing { dependent vertex Id -> density slope w.r.t. dependent vertex}

dlnDensityAtValue

public java.util.Map<java.lang.String,java.lang.Double> dlnDensityAtValue()

Description copied from class: Vertex

This is the same as dDensityAtValue except for the log of the density. For numerical stability a vertex may chose to override this method but if not overridden, the chain rule is used to calculate the derivative of the log of the density.

dlog(P)/dx = (dP/dx)*(1/P(x))

Overrides:

dlnDensityAtValue in class Vertex<java.lang.Integer>

sample

public java.lang.Integer sample()

Specified by:

sample in class Vertex<java.lang.Integer>

Returns:

a sample from the vertex's distribution. For non-probabilistic vertices, this will always be the same value.