JSci.maths.statistics
Class LognormalDistribution

java.lang.Object
  JSci.maths.statistics.ProbabilityDistribution
      JSci.maths.statistics.LognormalDistribution

public final class LognormalDistribution
extends ProbabilityDistribution

The LognormalDistribution class provides an object for encapsulating lognormal distributions.

Constructor Summary

LognormalDistribution()
Constructs a standard lognormal distribution.

LognormalDistribution(double mu, double sigma)
Constructs a lognormal distribution.

Method Summary

double	cumulative(double X) Cumulative lognormal distribution function.
double	getMuParameter() Returns the mu parameter.
double	getSigmaParameter() Returns the sigma parameter.
double	inverse(double probability) Inverse of the cumulative lognormal distribution function.
double	probability(double X) Probability density function of a lognormal distribution.

Methods inherited from class JSci.maths.statistics.ProbabilityDistribution

checkRange, checkRange, findRoot

Methods inherited from class java.lang.Object

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

Constructor Detail

LognormalDistribution

public LognormalDistribution()

Constructs a standard lognormal distribution.

LognormalDistribution

public LognormalDistribution(double mu,
                             double sigma)

Constructs a lognormal distribution.

Parameters:

mu - the mu parameter.

sigma - the sigma parameter.

Method Detail

getMuParameter

public double getMuParameter()

Returns the mu parameter.

getSigmaParameter

public double getSigmaParameter()

Returns the sigma parameter.

probability

public double probability(double X)

Probability density function of a lognormal distribution.

Specified by:

probability in class ProbabilityDistribution

Returns:

the probability that a stochastic variable x has the value X, i.e. P(x=X).

cumulative

public double cumulative(double X)

Cumulative lognormal distribution function.

Specified by:

cumulative in class ProbabilityDistribution

Returns:

the probability that a stochastic variable x is less then X, i.e. P(x<X).

inverse

public double inverse(double probability)

Inverse of the cumulative lognormal distribution function.

Specified by:

inverse in class ProbabilityDistribution

Returns:

the value X for which P(x<X).