Package jsl.utilities.random.rvariable

Interface RVariableIfc

All Superinterfaces:

java.util.function.DoubleSupplier, GetRandomNumberStreamIfc, GetValueIfc, NewAntitheticInstanceIfc, PreviousValueIfc, RandomIfc, RNStreamControlIfc, SampleIfc, SetRandomNumberStreamIfc

All Known Implementing Classes:

AbstractRVariable, AR1NormalRV, BernoulliRV, BetaRV, BinomialRV, ChiSquaredRV, ConstantRV, DEmpiricalRV, DUniformRV, EmpiricalRV, ExponentialRV, GammaRV, GeneralizedBetaRV, GeometricRV, Hyper2ExponentialRV, InverseCDFRV, JohnsonBRV, LaplaceRV, LogLogisticRV, LognormalRV, MixtureRV, NegativeBinomialRV, NormalRV, PearsonType5RV, PearsonType6RV, PoissonRV, ShiftedGeometricRV, ShiftedRV, StudentTRV, TriangularRV, TruncatedRV, UniformRV, VConstantRV, WeibullRV

public interface RVariableIfc
extends RandomIfc, NewAntitheticInstanceIfc, PreviousValueIfc, java.util.function.DoubleSupplier

An interface for defining random variables. The methods sample() and getValue() gets a new value of the random variable sampled accordingly. The method getPreviousValue() returns the value from the last call to sample() or getValue(). The value returned by getPreviousValue() stays the same until the next call to sample() or getValue(). The methods sample() or getValue() always get the next random value. If sample() or getValue() is never called then getPreviousValue() returns Double.NaN. Use sample() or getValue() to get a new random value and use getPreviousValue() to get the last sampled value.

The preferred approach to creating random variables is to sub-class AbstractRVariable.

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static class	RVariableIfc.RVType	The set of pre-defined distribution types

Method Summary

Modifier and Type	Method	Description
default java.util.stream.DoubleStream	asDoubleStream()	Turns the doubles into a DoubleStream for the Stream API
default double	getAsDouble()	This method facilitates turning instances of RVariableIfc into Java DoubleStream for use in the Stream API
default double	getSumOfValues(int n)
default double	getValue()	This method simply returns the value.
default RVariableIfc	newInstance()
RVariableIfc	newInstance(RNStreamIfc rng)

Methods inherited from interface jsl.utilities.random.rng.GetRandomNumberStreamIfc

getRandomNumberStream, getStreamNumber

Methods inherited from interface jsl.utilities.random.rvariable.NewAntitheticInstanceIfc

newAntitheticInstance

Methods inherited from interface jsl.utilities.PreviousValueIfc

getPreviousValue

Methods inherited from interface jsl.utilities.random.rng.RNStreamControlIfc

advanceToNextSubstream, getAntitheticOption, resetStartStream, resetStartSubstream, setAntitheticOption

Methods inherited from interface jsl.utilities.random.SampleIfc

sample, sample, sample

Methods inherited from interface jsl.utilities.random.rng.SetRandomNumberStreamIfc

setRandomNumberStream, setRandomNumberStream

Method Detail

getValue

default double getValue()

Description copied from interface: GetValueIfc

This method simply returns the value.

Specified by:

getValue in interface GetValueIfc

Returns:

returns a sampled values

getSumOfValues

default double getSumOfValues(int n)

Parameters:

n - the number of values to sum, must be 1 or more

Returns:

the sum of n values of getValue()

newInstance

RVariableIfc newInstance(RNStreamIfc rng)

Parameters:

rng - the RNStreamIfc to use

Returns:

a new instance with same parameter values

newInstance

default RVariableIfc newInstance()

Returns:

a new instance with same parameter values, with a different stream

getAsDouble

default double getAsDouble()

This method facilitates turning instances of RVariableIfc into Java DoubleStream for use in the Stream API

Specified by:

getAsDouble in interface java.util.function.DoubleSupplier

Returns:

the generated random number using sample()

asDoubleStream

default java.util.stream.DoubleStream asDoubleStream()

Turns the doubles into a DoubleStream for the Stream API

Returns:

a DoubleStream representation of the random variable