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@stdlib/stats-base-dists-t-cdf

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Student's t distribution cumulative distribution function (CDF).

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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 cumulative distribution function (CDF) for a Student's t distribution. * * @param x - input value * @returns evaluated CDF */ type Unary = ( x: number ) => number; /** * Interface for the cumulative distribution function (CDF) of a Student's t distribution. */ interface CDF { /** * Evaluates the cumulative distribution function (CDF) for a Student's t distribution with degrees of freedom `v` at a value `x`. * * ## Notes * * - If provided a non-positive value for `v`, the function returns `NaN`. * * @param x - input value * @param v - degrees of freedom * @returns evaluated CDF * * @example * var y = cdf( 2.0, 0.1 ); * // returns ~0.611 * * @example * var y = cdf( 1.0, 2.0 ); * // returns ~0.789 * * @example * var y = cdf( -1.0, 4.0 ); * // returns ~0.187 * * @example * var y = cdf( NaN, 1.0 ); * // returns NaN * * @example * var y = cdf( 0.0, NaN ); * // returns NaN * * @example * var y = cdf( 2.0, -1.0 ); * // returns NaN */ ( x: number, v: number ): number; /** * Returns a function for evaluating the cumulative distribution function (CDF) for a Student's t distribution with degrees of freedom `v`. * * @param v - degrees of freedom * @returns CDF * * @example * var mycdf = cdf.factory( 0.5 ); * var y = mycdf( 3.0 ); * // returns ~0.816 * * y = mycdf( 1.0 ); * // returns ~0.699 */ factory( v: number ): Unary; } /** * Student's t distribution cumulative distribution function (CDF). * * @param x - input value * @param v - degrees of freedom * @returns evaluated CDF * * @example * var y = cdf( 2.0, 0.1 ); * // returns ~0.611 * * y = cdf( 1.0, 2.0 ); * // returns ~0.789 * * y = cdf( -1.0, 4.0 ); * // returns ~0.187 * * var mycdf = cdf.factory( 0.5 ); * y = mycdf( 3.0 ); * // returns ~0.816 * * y = mycdf( 1.0 ); * // returns ~0.699 */ declare var cdf: CDF; // EXPORTS // export = cdf;