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@stdlib/stats-base-dists-geometric-logcdf

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Geometric distribution logarithm of 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 natural logarithm of the cumulative distribution function (CDF) for a geometric distribution. * * @param x - input value * @returns evaluated logCDF */ type Unary = ( x: number ) => number; /** * Interface for the logarithm of the cumulative distribution function (CDF) of a geometric distribution. */ interface LogCDF { /** * Evaluates the logarithm of the cumulative distribution function (CDF) for a geometric distribution with success probability `p` at a value `x`. * * ## Notes * * - If `p < 0` or `p > 1`, the function returns `NaN`. * * @param x - input value * @param p - success probability * @returns evaluated logCDF * * @example * var y = logcdf( 2.0, 0.5 ); * // returns ~-0.134 * * @example * var y = logcdf( 2.0, 0.1 ); * // returns ~-1.306 * * @example * var y = logcdf( -1.0, 0.5 ); * // returns -Infinity * * @example * var y = logcdf( NaN, 0.5 ); * // returns NaN * * @example * var y = logcdf( 0.0, NaN ); * // returns NaN * * @example * // Invalid probability * var y = logcdf( 2.0, 1.4 ); * // returns NaN */ ( x: number, p: number ): number; /** * Returns a function for evaluating the logarithm of the cumulative distribution function (CDF) for a geometric distribution with success probability `p`. * * @param p - success probability * @returns logCDF * * @example * var mylogcdf = logcdf.factory( 0.5 ); * var y = mylogcdf( 3.0 ); * // returns ~-0.065 * * y = mylogcdf( 1.0 ); * // returns ~-0.288 */ factory( p: number ): Unary; } /** * Geometric distribution logarithm of cumulative distribution function (CDF). * * @param x - input value * @param p - success probability * @returns evaluated logCDF * * @example * var y = logcdf( 2.0, 0.5 ); * // returns ~-0.134 * * y = logcdf( 2.0, 0.1 ); * // returns ~-1.306 * * var mylogcdf = logcdf.factory( 0.5 ); * y = mylogcdf( 3.0 ); * // returns ~-0.065 * * y = mylogcdf( 1.0 ); * // returns ~-0.288 */ declare var logCDF: LogCDF; // EXPORTS // export = logCDF;