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@stdlib/stats-base-dists-logistic-quantile

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Logistic distribution quantile function.

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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 quantile function for a logistic distribution. * * ## Notes * * - If `p < 0` or `p > 1`, the function returns `NaN`. * * @param p - input value * @returns evaluated quantile function */ type Unary = ( p: number ) => number; /** * Interface for the quantile function of a logistic distribution. */ interface Quantile { /** * Evaluates the quantile function for a logistic distribution with location parameter `mu` and scale parameter `s` at a probability `p`. * * ## Notes * * - If `p < 0` or `p > 1`, the function returns `NaN`. * - If provided `s < 0`, the function returns `NaN`. * * @param p - input value * @param mu - location parameter * @param s - scale parameter * @returns evaluated quantile function * * @example * var y = quantile( 0.8, 0.0, 1.0 ); * // returns ~1.386 * * @example * var y = quantile( 0.5, 4.0, 2.0 ); * // returns 4.0 * * @example * var y = quantile( 1.1, 0.0, 1.0 ); * // returns NaN * * @example * var y = quantile( -0.2, 0.0, 1.0 ); * // returns NaN * * @example * var y = quantile( NaN, 0.0, 1.0 ); * // returns NaN * * @example * var y = quantile( 0.0, NaN, 1.0 ); * // returns NaN * * @example * var y = quantile( 0.0, 0.0, NaN ); * // returns NaN * * @example * // Negative scale parameter: * var y = quantile( 0.5, 0.0, -1.0 ); * // returns NaN */ ( p: number, mu: number, s: number ): number; /** * Returns a function for evaluating the quantile function for a logistic distribution. * * @param mu - location parameter * @param s - scale parameter * @returns quantile function * * @example * var myQuantile = quantile.factory( 10.0, 2.0 ); * var y = myQuantile( 0.5 ); * // returns 10.0 * * y = myQuantile( 0.8 ); * // returns ~12.773 */ factory( mu: number, s: number ): Unary; } /** * Logistic distribution quantile function. * * @param p - input value * @param mu - location parameter * @param s - scale parameter * @returns evaluated quantile function * * @example * var y = quantile( 0.8, 0.0, 1.0 ); * // returns ~1.386 * * var myQuantile = quantile.factory( 10.0, 2.0 ); * y = myQuantile( 0.5 ); * // returns 10.0 */ declare var quantile: Quantile; // EXPORTS // export = quantile;