Random

Random numbers.

Usage

var ns = require( '@stdlib/random' );

ns

Namespace containing random number functionality.

var arr = ns.normal( [ 3, 3 ], 2.0, 5.0 );
// returns <ndarray>

The namespace exports the following functions to sample and shuffle elements from an array:

• sample( x[, options] ): sample elements from an array-like object.
• shuffle( arr[, options] ): shuffle elements of an array-like object.

The namespace contains the following functions for generating pseudorandom values drawn from probability distributions:

• arcsine( shape, a, b[, options] ): generate pseudorandom numbers drawn from an arcsine distribution.
• bernoulli( shape, p[, options] ): generate pseudorandom numbers drawn from a Bernoulli distribution.
• beta( shape, a, b[, options] ): generate pseudorandom numbers drawn from a beta distribution.
• betaprime( shape, alpha, beta[, options] ): generate pseudorandom numbers drawn from a betaprime distribution.
• binomial( shape, n, p[, options] ): generate pseudorandom numbers drawn from a binomial distribution.
• cauchy( shape, x0, gamma[, options] ): generate pseudorandom numbers drawn from a Cauchy distribution.
• chi( shape, k[, options] ): generate pseudorandom numbers drawn from a chi distribution.
• chisquare( shape, k[, options] ): generate pseudorandom numbers drawn from a chi-square distribution.
• cosine( shape, mu, s[, options] ): generate pseudorandom numbers drawn from a raised cosine distribution.
• discreteUniform( shape, a, b[, options] ): generate pseudorandom numbers drawn from a discrete uniform distribution.
• erlang( shape, k, lambda[, options] ): generate pseudorandom numbers drawn from an Erlang distribution.
• exponential( shape, lambda[, options] ): generate pseudorandom numbers drawn from an exponential distribution.
• f( shape, d1, d2[, options] ): generate pseudorandom numbers drawn from an F distribution.
• frechet( shape, alpha, s, m[, options] ): generate pseudorandom numbers drawn from a Fréchet distribution.
• gamma( shape, alpha, beta[, options] ): generate pseudorandom numbers drawn from a gamma distribution.
• geometric( shape, p[, options] ): generate pseudorandom numbers drawn from a geometric distribution.
• gumbel( shape, mu, beta[, options] ): generate pseudorandom numbers drawn from a Gumbel distribution.
• hypergeometric( shape, N, K, n[, options] ): generate pseudorandom numbers drawn from a hypergeometric distribution.
• invgamma( shape, alpha, beta[, options] ): generate pseudorandom numbers drawn from an inverse gamma distribution.
• kumaraswamy( shape, a, b[, options] ): generate pseudorandom numbers drawn from a Kumaraswamy distribution.
• laplace( shape, mu, b[, options] ): generate pseudorandom numbers drawn from a Laplace (double exponential) distribution.
• levy( shape, mu, c[, options] ): generate pseudorandom numbers drawn from a Lévy distribution.
• logistic( shape, mu, s[, options] ): generate pseudorandom numbers drawn from a logistic distribution.
• lognormal( shape, mu, sigma[, options] ): generate pseudorandom numbers drawn from a lognormal distribution.
• negativeBinomial( shape, r, p[, options] ): generate pseudorandom numbers drawn from a negative binomial distribution.
• normal( shape, mu, sigma[, options] ): generate pseudorandom numbers drawn from a normal distribution.
• pareto1( shape, alpha, beta[, options] ): generate pseudorandom numbers drawn from a Pareto (Type I) distribution.
• poisson( shape, lambda[, options] ): generate pseudorandom numbers drawn from a Poisson distribution.
• rayleigh( shape, sigma[, options] ): generate pseudorandom numbers drawn from a Rayleigh distribution.
• t( shape, v[, options] ): generate pseudorandom numbers drawn from a Student's t-distribution.
• triangular( shape, a, b, c[, options] ): generate pseudorandom numbers drawn from a triangular distribution.
• uniform( shape, a, b[, options] ): generate pseudorandom numbers drawn from a continuous uniform distribution.
• weibull( shape, k, lambda[, options] ): generate pseudorandom numbers drawn from a Weibull distribution.

The namespace contains the following sub-namespaces:

• array: pseudorandom number generator (PRNG) array creation functions.
• base: base (i.e., lower-level) pseudorandom number generators (PRNGs).
• iterators: pseudorandom number generator (PRNG) iterators.
• streams: pseudorandom number generator (PRNG) streams.
• strided: pseudorandom number generator (PRNG) strided array functions.

Examples

var logEach = require( '@stdlib/console/log-each' );
var ndarray2array = require( '@stdlib/ndarray/to-array' );
var ns = require( '@stdlib/random' );

// Create a function for generating arrays originating from the same state:
var random = ns.normal.factory({
    'state': ns.normal.state,
    'copy': true
});

// Generate 3 one-dimensional arrays:
var x1 = random( [ 5 ], 2.0, 5.0 );
var x2 = random( [ 5 ], 2.0, 5.0 );
var x3 = random( [ 5 ], 2.0, 5.0 );

// Print the contents:
logEach( '%f, %f, %f', ndarray2array( x1 ), ndarray2array( x2 ), ndarray2array( x3 ) );

// Create another function for generating random arrays with the original state:
random = ns.normal.factory({
    'state': ns.normal.state,
    'copy': true
});

// Generate a two-dimensional array which replicates the above pseudorandom number generation sequence:
var x4 = random( [ 3, 5 ], 2.0, 5.0 );

// Convert to a list of nested arrays:
var arr = ndarray2array( x4 );

// Print the contents:
console.log( '' );
logEach( '%f, %f, %f', arr[ 0 ], arr[ 1 ], arr[ 2 ] );