Octave Statistical Distribution Functions


 - Function File:  beta_cdf (X, A, B)
     For each element of X, returns the CDF at X of the beta
     distribution with parameters A and B, i.e., PROB (beta (A, B) <=
     X).

 - Function File:  beta_inv (X, A, B)
     For each component of X, compute the quantile (the inverse of the
     CDF) at X of the Beta distribution with parameters A and B.

 - Function File:  beta_pdf (X, A, B)
     For each element of X, returns the PDF at X of the beta
     distribution with parameters A and B.

 - Function File:  beta_rnd (A, B, R, C)
     Return an R by C matrix of random samples from the Beta
     distribution with parameters A and B.  Both A and B must be scalar
     or of size R by C.

     If R and C are omitted, the size of the result matrix is the
     common size of A and B.

 - Function File:  binomial_cdf (X, N, P)
     For each element of X, compute the CDF at X of the binomial
     distribution with parameters N and P.

 - Function File:  binomial_inv (X, N, P)
     For each element of X, compute the quantile at X of the binomial
     distribution with parameters N and P.

 - Function File:  binomial_pdf (X, N, P)
     For each element of X, compute the probability density function
     (PDF) at X of the binomial distribution with parameters N and P.

 - Function File:  binomial_rnd (N, P, R, C)
     Return an R by C matrix of random samples from the binomial
     distribution with parameters N and P.  Both N and P must be scalar
     or of size R by C.

     If R and C are omitted, the size of the result matrix is the
     common size of N and P.

 - Function File:  cauchy_cdf (X, LAMBDA, SIGMA)
     For each element of X, compute the cumulative distribution
     function (CDF) at X of the Cauchy distribution with location
     parameter LAMBDA and scale parameter SIGMA.  Default values are
     LAMBDA = 0, SIGMA = 1.

 - Function File:  cauchy_inv (X, LAMBDA, SIGMA)
     For each element of X, compute the quantile (the inverse of the
     CDF) at X of the Cauchy distribution with location parameter
     LAMBDA and scale parameter SIGMA.  Default values are LAMBDA = 0,
     SIGMA = 1.

 - Function File:  cauchy_pdf (X, LAMBDA, SIGMA)
     For each element of X, compute the probability density function
     (PDF) at X of the Cauchy distribution with location parameter
     LAMBDA and scale parameter SIGMA > 0.  Default values are LAMBDA =
     0, SIGMA = 1.

 - Function File:  cauchy_rnd (LAMBDA, SIGMA, R, C)
     Return an R by C matrix of random samples from the Cauchy
     distribution with parameters LAMBDA and SIGMA which must both be
     scalar or of size R by C.

     If R and C are omitted, the size of the result matrix is the
     common size of LAMBDA and SIGMA.

 - Function File:  chisquare_cdf (X, N)
     For each element of X, compute the cumulative distribution
     function (CDF) at X of the chisquare distribution with N degrees
     of freedom.

 - Function File:  chisquare_inv (X, N)
     For each element of X, compute the quantile (the inverse of the
     CDF) at X of the chisquare distribution with N degrees of freedom.

 - Function File:  chisquare_pdf (X, N)
     For each element of X, compute the probability density function
     (PDF) at X of the chisquare distribution with K degrees of freedom.

 - Function File:  chisquare_rnd (N, R, C)
     Return an R by C matrix of random samples from the chisquare
     distribution with N degrees of freedom.  N must be a scalar or of
     size R by C.

     If R and C are omitted, the size of the result matrix is the size
     of N.

 - Function File:  discrete_cdf (X, V, P)
     For each element of X, compute the cumulative distribution
     function (CDF) at X of a univariate discrete distribution which
     assumes the values in v with probabilities P.

 - Function File:  discrete_inv (X, V, P)
     For each component of X, compute the quantile (the inverse of the
     CDF) at X of the univariate distribution which assumes the values
     in V with probabilities P.

 - Function File:  discrete_pdf (X, V, P)
     For each element of X, compute the probability density function
     (pDF) at X of a univariate discrete distribution which assumes the
     values in V with probabilities P.

 - Function File:  discrete_rnd (N, V, P)
     Generate a row vector containing a random sample of size N from
     the univariate distribution which assumes the values in V with
     probabilities P.

     Currently, N must be a scalar.

 - Function File:  empirical_cdf (X, DATA)
     For each element of X, compute the cumulative distribution
     function (CDF) at X of the empirical distribution obtained from
     the univariate sample DATA.

 - Function File:  empirical_inv (X, DATA)
     For each element of X, compute the quantile (the inverse of the
     CDF) at X of the empirical distribution obtained from the
     univariate sample DATA.

 - Function File:  empirical_pdf (X, DATA)
     For each element of X, compute the probability density function
     (PDF) at X of the empirical distribution obtained from the
     univariate sample DATA.

 - Function File:  empirical_rnd (N, DATA)
     Generate a bootstrap sample of size N from the empirical
     distribution obtained from the univariate sample DATA.

 - Function File:  exponential_cdf (X, LAMBDA)
     For each element of X, compute the cumulative distribution
     function (CDF) at X of the exponential distribution with parameter
     LAMBDA.

     The arguments can be of common size or scalar.

 - Function File:  exponential_inv (X, LAMBDA)
     For each element of X, compute the quantile (the inverse of the
     CDF) at X of the exponential distribution with parameter LAMBDA.

 - Function File:  exponential_pdf (X, LAMBDA)
     For each element of X, compute the probability density function
     (PDF) of the exponential distribution with parameter LAMBDA.

 - Function File:  exponential_rnd (LAMBDA, R, C)
     Return an R by C matrix of random samples from the exponential
     distribution with parameter LAMBDA, which must be a scalar or of
     size R by C.

     If R and C are omitted, the size of the result matrix is the size
     of LAMBDA.

 - Function File:  f_cdf (X, M, N)
     For each element of X, compute the CDF at X of the F distribution
     with M and N degrees of freedom, i.e., PROB (F (M, N) <= X).

 - Function File:  f_inv (X, M, N)
     For each component of X, compute the quantile (the inverse of the
     CDF) at X of the F distribution with parameters M and N.

 - Function File:  f_pdf (X, M, N)
     For each element of X, compute the probability density function
     (PDF) at X of the F distribution with M and N degrees of freedom.

 - Function File:  f_rnd (M, N, R, C)
     Return an R by C matrix of random samples from the F distribution
     with M and N degrees of freedom.  Both M and N must be scalar or
     of size R by C.

     If R and C are omitted, the size of the result matrix is the
     common size of M and N.

 - Function File:  gamma_cdf (X, A, B)
     For each element of X, compute the cumulative distribution
     function (CDF) at X of the Gamma distribution with parameters A
     and B.

 - Function File:  gamma_inv (X, A, B)
     For each component of X, compute the quantile (the inverse of the
     CDF) at X of the Gamma distribution with parameters A and B.

 - Function File:  gamma_pdf (X, A, B)
     For each element of X, return the probability density function
     (PDF) at X of the Gamma distribution with parameters A and B.

 - Function File:  gamma_rnd (A, B, R, C)
     Return an R by C matrix of random samples from the Gamma
     distribution with parameters A and B.  Both A and B must be scalar
     or of size R by C.

     If R and C are omitted, the size of the result matrix is the
     common size of A and B.

 - Function File:  geometric_cdf (X, P)
     For each element of X, compute the CDF at X of the geometric
     distribution with parameter P.

 - Function File:  geometric_inv (X, P)
     For each element of X, compute the quantile at X of the geometric
     distribution with parameter P.

 - Function File:  geometric_pdf (X, P)
     For each element of X, compute the probability density function
     (PDF) at X of the geometric distribution with parameter P.

 - Function File:  geometric_rnd (P, R, C)
     Return an R by C matrix of random samples from the geometric
     distribution with parameter P, which must be a scalar or of size R
     by C.

     If R and C are omitted, the size of the result matrix is the size
     of P.

 - Function File:  hypergeometric_cdf (X, M, T, N)
     Compute the cumulative distribution function (CDF) at X of the
     hypergeometric distribution with parameters M, T, and N.  This is
     the probability of obtaining not more than X marked items when
     randomly drawing a sample of size N without replacement from a
     population of total size T containing M marked items.

     The parameters M, T, and N must positive integers with M and N not
     greater than T.

 - Function File:  hypergeometric_inv (X, M, T, N)
     For each element of X, compute the quantile at X of the
     hypergeometric distribution with parameters M, T, and N.

     The parameters M, T, and N must positive integers with M and N not
     greater than T.

 - Function File:  hypergeometric_pdf (X, M, T, N)
     Compute the probability density function (PDF) at X of the
     hypergeometric distribution with parameters M, T, and N. This is
     the probability of obtaining X marked items when randomly drawing
     a sample of size N without replacement from a population of total
     size T containing M marked items.

     The arguments must be of common size or scalar.

 - Function File:  hypergeometric_rnd (N_SIZE, M, T, N)
     Generate a row vector containing a random sample of size N_SIZE
     from the hypergeometric distribution with parameters M, T, and N.

     The parameters M, T, and N must positive integers with M and N not
     greater than T.

 - Function File:  kolmogorov_smirnov_cdf (X, TOL)
     Return the CDF at X of the Kolmogorov-Smirnov distribution,
                   Inf
          Q(x) =   SUM    (-1)^k exp(-2 k^2 x^2)
                 k = -Inf

     for X > 0.

     The optional parameter TOL specifies the precision up to which the
     series should be evaluated;  the default is TOL = `eps'.

 - Function File:  laplace_cdf (X)
     For each element of X, compute the cumulative distribution
     function (CDF) at X of the Laplace distribution.

 - Function File:  laplace_inv (X)
     For each element of X, compute the quantile (the inverse of the
     CDF) at X of the Laplace distribution.

 - Function File:  laplace_pdf (X)
     For each element of X, compute the probability density function
     (PDF) at X of the Laplace distribution.

 - Function File:  laplace_rnd (R, C)
     Return an R by C matrix of random numbers from the Laplace
     distribution.

 - Function File:  logistic_cdf (X)
     For each component of X, compute the CDF at X of the logistic
     distribution.

 - Function File:  logistic_inv (X)
     For each component of X, compute the quantile (the inverse of the
     CDF) at X of the logistic distribution.

 - Function File:  logistic_pdf (X)
     For each component of X, compute the PDF at X of the logistic
     distribution.

 - Function File:  logistic_rnd (R, C)
     Return an R by C matrix of random numbers from the logistic
     distribution.

 - Function File:  lognormal_cdf (X, A, V)
     For each element of X, compute the cumulative distribution
     function (CDF) at X of the lognormal distribution with parameters
     A and V.  If a random variable follows this distribution, its
     logarithm is normally distributed with mean `log (A)' and variance
     V.

     Default values are A = 1, V = 1.

 - Function File:  lognormal_inv (X, A, V)
     For each element of X, compute the quantile (the inverse of the
     CDF) at X of the lognormal distribution with parameters A and V.
     If a random variable follows this distribution, its logarithm is
     normally distributed with mean `log (A)' and variance V.

     Default values are A = 1, V = 1.

 - Function File:  lognormal_pdf (X, A, V)
     For each element of X, compute the probability density function
     (PDF) at X of the lognormal distribution with parameters A and V.
     If a random variable follows this distribution, its logarithm is
     normally distributed with mean `log (A)' and variance V.

     Default values are A = 1, V = 1.

 - Function File:  lognormal_rnd (A, V, R, C)
     Return an R by C matrix of random samples from the lognormal
     distribution with parameters A and V. Both A and V must be scalar
     or of size R by C.

     If R and C are omitted, the size of the result matrix is the
     common size of A and V.

 - Function File:  normal_cdf (X, M, V)
     For each element of X, compute the cumulative distribution
     function (CDF) at X of the normal distribution with mean M and
     variance V.

     Default values are M = 0, V = 1.

 - Function File:  normal_inv (X, M, V)
     For each element of X, compute the quantile (the inverse of the
     CDF) at X of the normal distribution with mean M and variance V.

     Default values are M = 0, V = 1.

 - Function File:  normal_pdf (X, M, V)
     For each element of X, compute the probability density function
     (PDF) at X of the normal distribution with mean M and variance V.

     Default values are M = 0, V = 1.

 - Function File:  normal_rnd (M, V, R, C)
     Return an R by C matrix of random samples from the normal
     distribution with parameters M and V.  Both M and V must be scalar
     or of size R by C.

     If R and C are omitted, the size of the result matrix is the
     common size of M and V.

 - Function File:  pascal_cdf (X, N, P)
     For each element of X, compute the CDF at x of the Pascal
     (negative binomial) distribution with parameters N and P.

     The number of failures in a Bernoulli experiment with success
     probability P before the N-th success follows this distribution.

 - Function File:  pascal_inv (X, N, P)
     For each element of X, compute the quantile at X of the Pascal
     (negative binomial) distribution with parameters N and P.

     The number of failures in a Bernoulli experiment with success
     probability P before the N-th success follows this distribution.

 - Function File:  pascal_pdf (X, N, P)
     For each element of X, compute the probability density function
     (PDF) at X of the Pascal (negative binomial) distribution with
     parameters N and P.

     The number of failures in a Bernoulli experiment with success
     probability P before the N-th success follows this distribution.

 - Function File:  pascal_rnd (N, P, R, C)
     Return an R by C matrix of random samples from the Pascal
     (negative binomial) distribution with parameters N and P.  Both N
     and P must be scalar or of size R by C.

     If R and C are omitted, the size of the result matrix is the
     common size of N and P.

 - Function File:  poisson_cdf (X, LAMBDA)
     For each element of X, compute the cumulative distribution
     function (CDF) at X of the Poisson distribution with parameter
     lambda.

 - Function File:  poisson_inv (X, LAMBDA)
     For each component of X, compute the quantile (the inverse of the
     CDF) at X of the Poisson distribution with parameter LAMBDA.

 - Function File:  poisson_pdf (X, LAMBDA)
     For each element of X, compute the probability density function
     (PDF) at X of the poisson distribution with parameter LAMBDA.

 - Function File:  poisson_rnd (LAMBDA, R, C)
     Return an R by C matrix of random samples from the Poisson
     distribution with parameter LAMBDA, which must be a scalar or of
     size R by C.

     If R and C are omitted, the size of the result matrix is the size
     of LAMBDA.

 - Function File:  stdnormal_cdf (X)
     For each component of X, compute the CDF of the standard normal
     distribution at X.

 - Function File:  stdnormal_inv (X)
     For each component of X, compute compute the quantile (the inverse
     of the CDF) at X of the standard normal distribution.

 - Function File:  stdnormal_pdf (X)
     For each element of X, compute the probability density function
     (PDF) of the standard normal distribution at X.

 - Function File:  stdnormal_rnd (R, C)
     Return an R by C matrix of random numbers from the standard normal
     distribution.

 - Function File:  t_cdf (X, N)
     For each element of X, compute the CDF at X of the t (Student)
     distribution with N degrees of freedom, i.e., PROB (t(N) <= X).

 - Function File:  t_inv (X, N)
     For each component of X, compute the quantile (the inverse of the
     CDF) at X of the t (Student) distribution with parameter N.

 - Function File:  t_pdf (X, N)
     For each element of X, compute the probability density function
     (PDF) at X of the T (Student) distribution with N degrees of
     freedom.

 - Function File:  t_rnd (N, R, C)
     Return an R by C matrix of random samples from the t (Student)
     distribution with N degrees of freedom.  N must be a scalar or of
     size R by C.

     If R and C are omitted, the size of the result matrix is the size
     of N.

 - Function File:  uniform_cdf (X, A, B)
     Return the CDF at X of the uniform distribution on [A, B], i.e.,
     PROB (uniform (A, B) <= x).

     Default values are A = 0, B = 1.

 - Function File:  uniform_inv (X, A, B)
     For each element of X, compute the quantile (the inverse of the
     CDF) at X of the uniform distribution on [A, B].

     Default values are A = 0, B = 1.

 - Function File:  uniform_pdf (X, A, B)
     For each element of X, compute the PDF at X of the uniform
     distribution on [A, B].

     Default values are A = 0, B = 1.

 - Function File:  uniform_rnd (A, B, R, C)
     Return an R by C matrix of random samples from the uniform
     distribution on [A, B].  Both A and B must be scalar or of size R
     by C.

     If R and C are omitted, the size of the result matrix is the
     common size of A and B.

 - Function File:  weibull_cdf (X, ALPHA, SIGMA)
     Compute the cumulative distribution function (CDF) at X of the
     Weibull distribution with shape parameter ALPHA and scale
     parameter SIGMA, which is

          1 - exp(-(x/sigma)^alpha)

     for X >= 0.

 - Function File:  weibull_inv (X, LAMBDA, ALPHA)
     Compute the quantile (the inverse of the CDF) at X of the Weibull
     distribution with shape parameter ALPHA and scale parameter SIGMA.

 - Function File:  weibull_pdf (X, ALPHA, SIGMA)
     Compute the probability density function (PDF) at X of the Weibull
     distribution with shape parameter ALPHA and scale parameter SIGMA
     which is given by

             alpha * sigma^(-alpha) * x^(alpha-1) * exp(-(x/sigma)^alpha)

     for X > 0.

 - Function File:  weibull_rnd (ALPHA, SIGMA, R, C)
     Return an R by C matrix of random samples from the Weibull
     distribution with parameters ALPHA and SIGMA which must be scalar
     or of size R by C.

     If R and C are omitted, the size of the result matrix is the
     common size of ALPHA and SIGMA.

 - Function File:  wiener_rnd (T, D, N)
     Return a simulated realization of the D-dimensional Wiener Process
     on the interval [0,T].  If D is omitted, D = 1 is used. The first
     column of the return matrix contains time, the remaining columns
     contain the Wiener process.

     The optional parameter N gives the number of summands used for
     simulating the process over an interval of length 1.  If N is
     omitted, N = 1000 is used.

 

&nbps