Package org.apache.commons.rng.sampling.distribution

Class LogNormalSampler

java.lang.Object

org.apache.commons.rng.sampling.distribution.LogNormalSampler

All Implemented Interfaces:

ContinuousSampler, SharedStateContinuousSampler, SharedStateSampler<SharedStateContinuousSampler>

public class LogNormalSampler
extends Object
implements SharedStateContinuousSampler

Sampling from a log-normal distribution.

Since:

1.1

Constructor Summary

Constructors

Constructor	Description
LogNormalSampler(NormalizedGaussianSampler gaussian, double scale, double shape)

Method Summary

Modifier and Type	Method	Description
static SharedStateContinuousSampler	of(NormalizedGaussianSampler gaussian, double scale, double shape)	Create a new log-normal distribution sampler.
double	sample()	Creates a sample.
String	toString()
SharedStateContinuousSampler	withUniformRandomProvider(UniformRandomProvider rng)	Create a new instance of the sampler with the same underlying state using the given uniform random provider as the source of randomness.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

LogNormalSampler

public LogNormalSampler(NormalizedGaussianSampler gaussian,
                        double scale,
                        double shape)

Parameters:

gaussian - N(0,1) generator.

scale - Scale of the log-normal distribution.

shape - Shape of the log-normal distribution.

Throws:

IllegalArgumentException - if scale < 0 or shape <= 0.

Method Detail

sample

public double sample()

Creates a sample.

Specified by:

sample in interface ContinuousSampler

Returns:

a sample.

toString

public String toString()

Overrides:

toString in class Object

withUniformRandomProvider

public SharedStateContinuousSampler withUniformRandomProvider(UniformRandomProvider rng)

Create a new instance of the sampler with the same underlying state using the given uniform random provider as the source of randomness.

Note: This function is available if the underlying NormalizedGaussianSampler is a SharedStateSampler. Otherwise a run-time exception is thrown.

Specified by:

withUniformRandomProvider in interface SharedStateSampler<SharedStateContinuousSampler>

Parameters:

rng - Generator of uniformly distributed random numbers.

Returns:

the sampler

Throws:

UnsupportedOperationException - if the underlying sampler is not a SharedStateSampler or does not return a NormalizedGaussianSampler when sharing state.

Since:

1.3

of

public static SharedStateContinuousSampler of(NormalizedGaussianSampler gaussian,
                                              double scale,
                                              double shape)

Create a new log-normal distribution sampler.

Note: The shared-state functionality is available if the NormalizedGaussianSampler is a SharedStateSampler. Otherwise a run-time exception will be thrown when the sampler is used to share state.

Parameters:

gaussian - N(0,1) generator.

scale - Scale of the log-normal distribution.

shape - Shape of the log-normal distribution.

Returns:

the sampler

Throws:

IllegalArgumentException - if scale < 0 or shape <= 0.

Since:

1.3

See Also:

withUniformRandomProvider(UniformRandomProvider)