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@stdlib/stats-base-dists-normal-mgf

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Normal distribution moment-generating function (MGF).

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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 /** * Evaluates the moment-generating function (MGF) of a normal distribution. * * @param t - input value * @returns evaluated MGF */ type Unary = ( t: number ) => number; /** * Interface for the moment-generating function (MGF) of a normal distribution. */ interface MGF { /** * Evaluates the moment-generating function (MGF) for a normal distribution with mean `mu` and standard deviation `sigma` at a value `t`. * * ## Notes * * - If provided `sigma < 0`, the function returns `NaN`. * * @param t - input value * @param mu - mean * @param sigma - standard deviation * @returns evaluated MGF * * @example * var y = mgf( 2.0, 0.0, 1.0 ); * // returns ~7.389 * * @example * var y = mgf( 0.0, 0.0, 1.0 ); * // returns 1.0 * * @example * var y = mgf( -1.0, 4.0, 2.0 ); * // returns ~0.1353 * * @example * var y = mgf( NaN, 0.0, 1.0 ); * // returns NaN * * @example * var y = mgf( 0.0, NaN, 1.0 ); * // returns NaN * * @example * var y = mgf( 0.0, 0.0, NaN ); * // returns NaN * * @example * var y = mgf( 2.0, 0.0, 0.0 ); * // returns NaN */ ( t: number, mu: number, sigma: number ): number; /** * Returns a function for evaluating the moment-generating function (MGF) of a normal distribution with mean `mu` and standard deviation `sigma`. * * @param mu - mean * @param sigma - standard deviation * @returns MGF * * @example * var mymgf = mgf.factory( 4.0, 2.0 ); * * var y = mymgf( 1.0 ); * // returns ~403.429 * * y = mymgf( 0.5 ); * // returns ~12.182 */ factory( mu: number, sigma: number ): Unary; } /** * Normal distribution moment-generating function (MGF). * * @param t - input value * @param mu - mean * @param sigma - standard deviation * @returns evaluated MGF * * @example * var y = mgf( 2.0, 0.0, 1.0 ); * // returns ~7.389 * * y = mgf( 0.0, 0.0, 1.0 ); * // returns 1.0 * * y = mgf( -1.0, 4.0, 2.0 ); * // returns ~0.1353 * * var mymgf = mgf.factory( 4.0, 2.0 ); * * y = mymgf( 1.0 ); * // returns ~403.429 * * y = mymgf( 0.5 ); * // returns ~12.182 */ declare var mgf: MGF; // EXPORTS // export = mgf;