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@stdlib/simulate-iter-awun

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Create an iterator which introduces additive white uniform noise.

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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 { Iterator as Iter, IterableIterator } from '@stdlib/types/iter'; import * as random from '@stdlib/types/random'; // Define a union type representing both iterable and non-iterable iterators: type Iterator = Iter | IterableIterator; /** * Interface defining function options. */ interface Options { /** * Pseudorandom number generator which generates uniformly distributed pseudorandom numbers on the interval `[0,1)`. * * ## Notes * * - If provided, the `state` and `seed` options are ignored. In order to seed the returned iterator, one must seed the provided `prng` (assuming the provided `prng` is seedable). */ prng?: random.PRNG; /** * Pseudorandom number generator state. * * ## Notes * * - If provided, the `seed` option is ignored. */ state?: random.PRNGStateMT19937; /** * Pseudorandom number generator seed. */ seed?: random.PRNGSeedMT19937; /** * Specifies whether to copy a provided pseudorandom number generator state. * * ## Notes * * - Setting this option to `false` allows sharing state between two or more pseudorandom number generators. Setting this option to `true` ensures that a returned iterator has exclusive control over its internal state. */ copy?: boolean; } /** * Interface defining a returned iterator. */ interface ExtendedIter extends Iter { /** * Underlying PRNG. */ readonly PRNG: random.PRNG; /** * PRNG seed. */ readonly seed: random.PRNGSeedMT19937 | null; /** * PRNG seed length. */ readonly seedLength: number | null; /** * PRNG state. */ state: random.PRNGStateMT19937 | null; /** * PRNG state length. */ readonly stateLength: number | null; /** * PRNG state size (in bytes). */ readonly byteLength: number | null; } /** * Interface defining a returned iterable iterator. */ interface ExtendedIterableIterator extends ExtendedIter { /** * Returns a new iterable iterator. * * @returns iterable iterator */ [Symbol.iterator](): IterableIterator; } // Define a union type representing both iterable and non-iterable returned iterators: type ExtendedIterator = ExtendedIter | ExtendedIterableIterator; /** * Returns an iterator which introduces additive white uniform noise with standard deviation `sigma`. * * @param iterator - input iterator * @param sigma - standard deviation of the noise * @param options - function options * @param options.prng - pseudorandom number generator for generating uniformly distributed pseudorandom numbers on the interval `[0,1)` * @param options.state - pseudorandom number generator state * @param options.seed - pseudorandom number generator seed * @param options.copy - boolean indicating whether to copy a provided pseudorandom number generator state (default: true) * @throws `sigma` must be a positive number * @throws must provide a valid state * @returns iterator * * @example * var iterSineWave = require( '@stdlib/simulate-iter-sine-wave' ); * * var sine = iterSineWave({ * 'iter': 100 * }); * * var it = iterawun( sine, 0.5 ); * * var v = it.next().value; * // returns <number> * * v = it.next().value; * // returns <number> * * v = it.next().value; * // returns <number> * * // ... */ declare function iterawun( iterator: Iterator, sigma: number, options?: Options ): ExtendedIterator; // EXPORTS // export = iterawun;