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Distributions

beta_cdf (x a, b) Function File
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).

beta_inv (x a, b) Function File
For each component of x compute the quantile (the inverse of the CDF) at x of the Beta distribution with parameters a and b.

beta_pdf (x a, b) Function File
For each element of x returns the PDF at x of the beta distribution with parameters a and b.

beta_rnd (a b, r, c) Function File
beta_rnd (a b, sz) Function File
Return an r by c or size (sz) 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.

binomial_cdf (x n, p) Function File
For each element of x compute the CDF at x of the binomial distribution with parameters n and p.

binomial_inv (x n, p) Function File
For each element of x compute the quantile at x of the binomial distribution with parameters n and p.

binomial_pdf (x n, p) Function File
For each element of x compute the probability density function (PDF) at x of the binomial distribution with parameters n and p.

binomial_rnd (n p, r, c) Function File
binomial_rnd (n p, sz) Function File
Return an r by c or a size (sz) 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.

cauchy_cdf (x lambda, sigma) Function File
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.

cauchy_inv (x lambda, sigma) Function File
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.

cauchy_pdf (x lambda, sigma) Function File
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.

cauchy_rnd (lambda sigma, r, c) Function File
cauchy_rnd (lambda sigma, sz) Function File
Return an r by c or a size (sz) 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.

chisquare_cdf (x n) Function File
For each element of x compute the cumulative distribution function (CDF) at x of the chisquare distribution with n degrees of freedom.

chisquare_inv (x n) Function File
For each element of x compute the quantile (the inverse of the CDF) at x of the chisquare distribution with n degrees of freedom.

chisquare_pdf (x n) Function File
For each element of x compute the probability density function (PDF) at x of the chisquare distribution with k degrees of freedom.

chisquare_rnd (n r, c) Function File
chisquare_rnd (n sz) Function File
Return an r by c or a size (sz) 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.

discrete_cdf (x v, p) Function File
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.

discrete_inv (x v, p) Function File
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.

discrete_pdf (x v, p) Function File
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.

discrete_rnd (n v, p) Function File
discrete_rnd (v p, r, c) Function File
discrete_rnd (v p, sz) Function File
Generate a row vector containing a random sample of size n from the univariate distribution which assumes the values in v with probabilities p. n must be a scalar.

If r and c are given create a matrix with r rows and c columns. Or if sz is a vector create a matrix of size sz.

empirical_cdf (x data) Function File
For each element of x compute the cumulative distribution function (CDF) at x of the empirical distribution obtained from the univariate sample data.

empirical_inv (x data) Function File
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.

empirical_pdf (x data) Function File
For each element of x compute the probability density function (PDF) at x of the empirical distribution obtained from the univariate sample data.

empirical_rnd (n data) Function File
empirical_rnd (data r, c) Function File
empirical_rnd (data sz) Function File
Generate a bootstrap sample of size n from the empirical distribution obtained from the univariate sample data.

If r and c are given create a matrix with r rows and c columns. Or if sz is a vector create a matrix of size sz.

exponential_cdf (x lambda) Function File
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.

exponential_inv (x lambda) Function File
For each element of x compute the quantile (the inverse of the CDF) at x of the exponential distribution with parameter lambda.

exponential_pdf (x lambda) Function File
For each element of x compute the probability density function (PDF) of the exponential distribution with parameter lambda.

exponential_rnd (lambda r, c) Function File
exponential_rnd (lambda sz) Function File
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. Or if sz is a vector create a matrix of size sz.

If r and c are omitted the size of the result matrix is the size of lambda.

f_cdf (x m, n) Function File
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).

f_inv (x m, n) Function File
For each component of x compute the quantile (the inverse of the CDF) at x of the F distribution with parameters m and n.

f_pdf (x m, n) Function File
For each element of x compute the probability density function (PDF) at x of the F distribution with m and n degrees of freedom.

f_rnd (m n, r, c) Function File
f_rnd (m n, sz) Function File
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 sz is a vector the random samples are in a matrix of size sz.

If r and c are omitted the size of the result matrix is the common size of m and n.

gamma_cdf (x a, b) Function File
For each element of x compute the cumulative distribution function (CDF) at x of the Gamma distribution with parameters a and b.

gamma_inv (x a, b) Function File
For each component of x compute the quantile (the inverse of the CDF) at x of the Gamma distribution with parameters a and b.

gamma_pdf (x a, b) Function File
For each element of x return the probability density function (PDF) at x of the Gamma distribution with parameters a and b.

gamma_rnd (a b, r, c) Function File
gamma_rnd (a b, sz) Function File
Return an r by c or a size (sz) 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.

geometric_cdf (x p) Function File
For each element of x compute the CDF at x of the geometric distribution with parameter p.

geometric_inv (x p) Function File
For each element of x compute the quantile at x of the geometric distribution with parameter p.

geometric_pdf (x p) Function File
For each element of x compute the probability density function (PDF) at x of the geometric distribution with parameter p.

geometric_rnd (p r, c) Function File
geometric_rnd (p sz) Function File
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 given create a matrix with r rows and c columns. Or if sz is a vector create a matrix of size sz.

hypergeometric_cdf (x m, t, n) Function File
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.

hypergeometric_inv (x m, t, n) Function File
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.

hypergeometric_pdf (x m, t, n) Function File
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.

hypergeometric_rnd (n_size m, t, n) Function File
hypergeometric_rnd (m t, n, r, c) Function File
hypergeometric_rnd (m t, n, sz) Function File
Generate a row vector containing a random sample of size n_size from the hypergeometric distribution with parameters m t, and n.

If r and c are given create a matrix with r rows and c columns. Or if sz is a vector create a matrix of size sz.

The parameters m t, and n must positive integers with m and n not greater than t.

kolmogorov_smirnov_cdf (x tol) Function File
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.

laplace_cdf (x) Function File
For each element of x compute the cumulative distribution function (CDF) at x of the Laplace distribution.

laplace_inv (x) Function File
For each element of x compute the quantile (the inverse of the CDF) at x of the Laplace distribution.

laplace_pdf (x) Function File
For each element of x compute the probability density function (PDF) at x of the Laplace distribution.

laplace_rnd (r c) Function File
laplace_rnd (sz); Function File
Return an r by c matrix of random numbers from the Laplace distribution. Or is sz is a vector create a matrix of sz.

logistic_cdf (x) Function File
For each component of x compute the CDF at x of the logistic distribution.

logistic_inv (x) Function File
For each component of x compute the quantile (the inverse of the CDF) at x of the logistic distribution.

logistic_pdf (x) Function File
For each component of x compute the PDF at x of the logistic distribution.

logistic_rnd (r c) Function File
logistic_rnd (sz) Function File
Return an r by c matrix of random numbers from the logistic distribution. Or is sz is a vector create a matrix of sz.

lognormal_cdf (x a, v) Function File
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.

lognormal_inv (x a, v) Function File
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.

lognormal_pdf (x a, v) Function File
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.

lognormal_rnd (a v, r, c) Function File
lognormal_rnd (a v, sz) Function File
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. Or if sz is a vector create a matrix of size sz.

If r and c are omitted the size of the result matrix is the common size of a and v.

normal_cdf (x m, v) Function File
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.

normal_inv (x m, v) Function File
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.

normal_pdf (x m, v) Function File
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.

normal_rnd (m v, r, c) Function File
normal_rnd (m v, sz) Function File
Return an r by c or size (sz) 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.

pascal_cdf (x n, p) Function File
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.

pascal_inv (x n, p) Function File
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.

pascal_pdf (x n, p) Function File
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.

pascal_rnd (n p, r, c) Function File
pascal_rnd (n p, sz) Function File
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. Or if sz is a vector create a matrix of size sz.

poisson_cdf (x lambda) Function File
For each element of x compute the cumulative distribution function (CDF) at x of the Poisson distribution with parameter lambda.

poisson_inv (x lambda) Function File
For each component of x compute the quantile (the inverse of the CDF) at x of the Poisson distribution with parameter lambda.

poisson_pdf (x lambda) Function File
For each element of x compute the probability density function (PDF) at x of the poisson distribution with parameter lambda.

poisson_rnd (lambda r, c) Function File
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.

stdnormal_cdf (x) Function File
For each component of x compute the CDF of the standard normal distribution at x.

stdnormal_inv (x) Function File
For each component of x compute compute the quantile (the inverse of the CDF) at x of the standard normal distribution.

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

stdnormal_rnd (r c) Function File
stdnormal_rnd (sz) Function File
Return an r by c or size (sz) matrix of random numbers from the standard normal distribution.

t_cdf (x n) Function File
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).

t_inv (x n) Function File
For each component of x compute the quantile (the inverse of the CDF) at x of the t (Student) distribution with parameter n.

t_pdf (x n) Function File
For each element of x compute the probability density function (PDF) at x of the t (Student) distribution with n degrees of freedom.

t_rnd (n r, c) Function File
t_rnd (n sz) Function File
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. Or if sz is a vector create a matrix of size sz.

If r and c are omitted the size of the result matrix is the size of n.

uniform_cdf (x a, b) Function File
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.

uniform_inv (x a, b) Function File
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.

uniform_pdf (x a, b) Function File
For each element of x compute the PDF at x of the uniform distribution on [a b].

Default values are a = 0 b = 1.

uniform_rnd (a b, r, c) Function File
uniform_rnd (a b, sz) Function File
Return an r by c or a size (sz) 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.

weibull_cdf (x alpha, sigma) Function File
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.

weibull_inv (x lambda, alpha) Function File
Compute the quantile (the inverse of the CDF) at x of the Weibull distribution with shape parameter alpha and scale parameter sigma.

weibull_pdf (x alpha, sigma) Function File
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.

weibull_rnd (alpha sigma, r, c) Function File
weibull_rnd (alpha sigma, sz) Function File
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. Or if sz is a vector return a matrix of size sz.

If r and c are omitted the size of the result matrix is the common size of alpha and sigma.

wiener_rnd (t d, n) Function File
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.