@stdlib/random-base-hypergeometric
Version:
Hypergeometric distributed pseudorandom numbers.
248 lines (223 loc) • 6.35 kB
TypeScript
/*
* @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;