Method Detail

• probability

  double probability(int x)

  For a random variable X whose values are distributed according to this distribution, this method returns P(X = x). In other words, this method represents the probability mass function (PMF) for the distribution.

  Parameters:

  x - the point at which the PMF is evaluated

  Returns:

  the value of the probability mass function at x

• cumulativeProbability

  double cumulativeProbability(int x)

  For a random variable X whose values are distributed according to this distribution, this method returns P(X <= x). In other words, this method represents the (cumulative) distribution function (CDF) for this distribution.

  Parameters:

  x - the point at which the CDF is evaluated

  Returns:

  the probability that a random variable with this distribution takes a value less than or equal to x

• cumulativeProbability

  double cumulativeProbability(int x0,
                             int x1)
                               throws NumberIsTooLargeException

  For a random variable X whose values are distributed according to this distribution, this method returns P(x0 < X <= x1).

  Parameters:

  x0 - the exclusive lower bound

  x1 - the inclusive upper bound

  Returns:

  the probability that a random variable with this distribution will take a value between x0 and x1, excluding the lower and including the upper endpoint

  Throws:

  NumberIsTooLargeException - if x0 > x1

• inverseCumulativeProbability

  int inverseCumulativeProbability(double p)
                                   throws OutOfRangeException

  Computes the quantile function of this distribution. For a random variable X distributed according to this distribution, the returned value is

  • inf{x in Z | P(X<=x) >= p} for 0 < p <= 1,
  • inf{x in Z | P(X<=x) > 0} for p = 0.

  If the result exceeds the range of the data type int, then Integer.MIN_VALUE or Integer.MAX_VALUE is returned.

  Parameters:

  p - the cumulative probability

  Returns:

  the smallest p-quantile of this distribution (largest 0-quantile for p = 0)

  Throws:

  OutOfRangeException - if p < 0 or p > 1

• getNumericalMean

  double getNumericalMean()

  Use this method to get the numerical value of the mean of this distribution.

  Returns:

  the mean or Double.NaN if it is not defined

• getNumericalVariance

  double getNumericalVariance()

  Use this method to get the numerical value of the variance of this distribution.

  Returns:

  the variance (possibly Double.POSITIVE_INFINITY or Double.NaN if it is not defined)

• getSupportLowerBound

  int getSupportLowerBound()

  Access the lower bound of the support. This method must return the same value as inverseCumulativeProbability(0). In other words, this method must return

  inf {x in Z | P(X <= x) > 0}.

  Returns:

  lower bound of the support (Integer.MIN_VALUE for negative infinity)

• getSupportUpperBound

  int getSupportUpperBound()

  Access the upper bound of the support. This method must return the same value as inverseCumulativeProbability(1). In other words, this method must return

  inf {x in R | P(X <= x) = 1}.

  Returns:

  upper bound of the support (Integer.MAX_VALUE for positive infinity)

• isSupportConnected

  boolean isSupportConnected()

  Use this method to get information about whether the support is connected, i.e. whether all integers between the lower and upper bound of the support are included in the support.

  Returns:

  whether the support is connected or not

• reseedRandomGenerator

  void reseedRandomGenerator(long seed)

  Reseed the random generator used to generate samples.

  Parameters:

  seed - the new seed

  Since:

  3.0

• sample

  int sample()

  Generate a random value sampled from this distribution.

  Returns:

  a random value

  Since:

  3.0

• sample

  int[] sample(int sampleSize)

  Generate a random sample from the distribution.

  Parameters:

  sampleSize - the number of random values to generate

  Returns:

  an array representing the random sample

  Throws:

  NotStrictlyPositiveException - if sampleSize is not positive

  Since:

  3.0