JSci.maths.statistics
Class FDistribution

java.lang.Object
  extended by JSci.maths.statistics.ProbabilityDistribution
      extended by JSci.maths.statistics.FDistribution

public final class FDistribution
extends ProbabilityDistribution

The FDistribution class provides an object for encapsulating F-distributions.


Constructor Summary
FDistribution(double dgrP, double dgrQ)
          Constructs an F-distribution.
 
Method Summary
 double cumulative(double X)
          Cumulative F-distribution function.
 double getDegreesOfFreedomP()
          Returns the degrees of freedom p.
 double getDegreesOfFreedomQ()
          Returns the degrees of freedom q.
 double inverse(double probability)
          Inverse of the cumulative F-distribution function.
 double probability(double X)
          Probability density function of an F-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

FDistribution

public FDistribution(double dgrP,
                     double dgrQ)
Constructs an F-distribution.

Parameters:
dgrP - degrees of freedom p.
dgrQ - degrees of freedom q.
Method Detail

getDegreesOfFreedomP

public double getDegreesOfFreedomP()
Returns the degrees of freedom p.


getDegreesOfFreedomQ

public double getDegreesOfFreedomQ()
Returns the degrees of freedom q.


probability

public double probability(double X)
Probability density function of an F-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 F-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 F-distribution function.

Specified by:
inverse in class ProbabilityDistribution
Returns:
the value X for which P(x<X).