Class Exponential

java.lang.Object
cern.colt.PersistentObject
cern.jet.random.AbstractDistribution
cern.jet.random.AbstractContinousDistribution
cern.jet.random.Exponential
All Implemented Interfaces:
DoubleFunction, IntFunction, Serializable, Cloneable
public class Exponential extends AbstractContinousDistribution
Exponential Distribution (aka Negative Exponential Distribution); See the math definition animated definition.

p(x) = lambda*exp(-x*lambda) for x >= 0, lambda > 0.

Instance methods operate on a user supplied uniform random number generator; they are unsynchronized.

Static methods operate on a default uniform random number generator; they are synchronized.

Version:
1.0, 09/24/99
See Also:

  • Field Details

    • lambda

      protected double lambda

    • shared

      protected static Exponential shared

  • Constructor Details

    • Exponential

      public Exponential(double lambda, RandomEngine randomGenerator)
      Constructs a Negative Exponential distribution.

  • Method Details

    • cdf

      public double cdf(double x)
      Returns the cumulative distribution function.

    • nextDouble

      public double nextDouble()
      Returns a random number from the distribution.
      Specified by:
      nextDouble in class AbstractDistribution

    • nextDouble

      public double nextDouble(double lambda)
      Returns a random number from the distribution; bypasses the internal state.

    • pdf

      public double pdf(double x)
      Returns the probability distribution function.

    • setState

      public void setState(double lambda)
      Sets the mean.

    • staticNextDouble

      public static double staticNextDouble(double lambda)
      Returns a random number from the distribution with the given lambda.

    • toString

      public String toString()
      Returns a String representation of the receiver.
      Overrides:
      toString in class Object

    • xstaticSetRandomGenerator

      private static void xstaticSetRandomGenerator(RandomEngine randomGenerator)
      Sets the uniform random number generated shared by all static methods.
      Parameters:
      randomGenerator - the new uniform random number generator to be shared.