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@stdlib/random-base-hypergeometric

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Hypergeometric distributed pseudorandom numbers.

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/* * @license Apache-2.0 * * Copyright (c) 2019 The Stdlib Authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ // TypeScript Version: 4.1 /// <reference types="@stdlib/types"/> import * as random from '@stdlib/types/random'; /** * Interface defining `factory` options. */ interface Options { /** * Pseudorandom number generator which generates uniformly distributed pseudorandom numbers. */ prng?: random.PRNG; /** * Pseudorandom number generator seed. */ seed?: random.PRNGSeedMT19937; /** * Pseudorandom number generator state. */ state?: random.PRNGStateMT19937; /** * Specifies whether to copy a provided pseudorandom number generator state. */ copy?: boolean; } /** * Interface for PRNG properties and methods. */ interface PRNG { /** * Generator name. */ readonly NAME: string; /** * Underlying pseudorandom number generator. */ readonly PRNG: random.PRNG; /** * PRNG seed. */ readonly seed: random.PRNGSeedMT19937; /** * PRNG seed length. */ readonly seedLength: number; /** * PRNG state. */ state: random.PRNGStateMT19937; /** * PRNG state length. */ readonly stateLength: number; /** * PRNG state size (in bytes). */ readonly byteLength: number; /** * Serializes the pseudorandom number generator as a JSON object. * * @returns JSON representation */ toJSON(): string; } /** * Interface for generating pseudorandom numbers from a hypergeometric distribution with pre-specified parameter values. */ interface NullaryFunction extends PRNG { /** * Returns a pseudorandom number drawn from a hypergeometric distribution. * * @returns pseudorandom number */ (): number; } /** * Interface for generating pseudorandom numbers from a hypergeometric distribution without pre-specified parameter values. */ interface TernaryFunction extends PRNG { /** * Returns a pseudorandom number drawn from a hypergeometric distribution. * * @param N - population size * @param K - subpopulation size * @param n - number of draws * @returns pseudorandom number */ ( N: number, K: number, n: number ): number; } /** * Interface for generating pseudorandom numbers drawn from a hypergeometric distribution. */ interface Random extends PRNG { /** * Returns pseudorandom number drawn from a hypergeometric distribution. * * ## Notes * * - `N`, `K`, and `n` must all be nonnegative integers; otherwise, the function returns `NaN`. * - If `n > N` or `K > N`, the function returns `NaN`. * * @param N - population size * @param K - subpopulation size * @param n - number of draws * @returns pseudorandom number * * @example * var v = hypergeometric( 10, 5, 7 ); * // returns <number> * * @example * var v = hypergeometric( 5, 3, 2 ); * // returns NaN */ ( N: number, K: number, n: number ): number; /** * Returns a pseudorandom number generator for generating random numbers from a hypergeometric distribution. * * ## Notes * * - When provided `N`, `K`, and `n`, the returned PRNG returns random variates drawn from the specified distribution. * * @param N - population size * @param K - subpopulation size * @param n - number of draws * @param options - function options * @param options.prng - pseudorandom number generator which generates uniformly distributed pseudorandom numbers * @param options.seed - pseudorandom number generator seed * @param options.state - pseudorandom number generator state * @param options.copy - boolean indicating whether to copy a provided pseudorandom number generator state (default: true) * @throws `N` must be a nonnegative integer * @throws `K` must be a nonnegative integer * @throws `n` must be a nonnegative integer * @throws `n` must be less than or equal to `N` * @throws `K` must be less than or equal to `N` * @throws must provide a valid state * @returns pseudorandom number generator * * @example * var rand = hypergeometric.factory( 10, 5, 7 ); * var v = rand(); * // returns <number> * * @example * var rand = hypergeometric.factory( 5, 3, 2, { * 'seed': 297 * }); * var v = rand(); * // returns <number> */ factory( N: number, K: number, n: number, options?: Options ): NullaryFunction; /** * Returns a pseudorandom number generator for generating random numbers from a hypergeometric distribution. * * ## Notes * * - When not provided `N`, `K`, and `n`, the returned PRNG requires that `N`, `K`, and `n` be provided at each invocation. * * @param options - function options * @param options.prng - pseudorandom number generator which generates uniformly distributed pseudorandom numbers * @param options.seed - pseudorandom number generator seed * @param options.state - pseudorandom number generator state * @param options.copy - boolean indicating whether to copy a provided pseudorandom number generator state (default: true) * @throws must provide a valid state * @returns pseudorandom number generator * * @example * var rand = hypergeometric.factory(); * var v = rand( 10, 5, 7 ); * // returns <number> * * @example * var rand = hypergeometric.factory({ * 'seed': 297 * }); * var v = rand( 5, 3, 2 ); * // returns <number> */ factory( options?: Options ): TernaryFunction; } /** * Returns pseudorandom number drawn from a hypergeometric distribution. * * ## Notes * * - `N`, `K`, and `n` must all be nonnegative integers; otherwise, the function returns `NaN`. * - If `n > N` or `K > N`, the function returns `NaN`. * * @param N - population size * @param K - subpopulation size * @param n - number of draws * @returns pseudorandom number * * @example * var v = hypergeometric( 10, 5, 7 ); * // returns <number> * * @example * var rand = hypergeometric.factory({ * 'seed': 297 * }); * var v = rand( 5, 3, 2 ); * // returns <number> */ declare var hypergeometric: Random; // EXPORTS // export = hypergeometric;