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@stdlib/stats-base-dists-discrete-uniform-logcdf

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Natural logarithm of the cumulative distribution function (CDF)for a discrete uniform distribution.

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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 discrete uniform 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 discrete uniform distribution. */ interface LogCDF { /** * Evaluates the natural logarithm of the cumulative distribution function (CDF) for a discrete uniform distribution with minimum support `a` and maximum support `b` at a value `x`. * * ## Notes * * - If `a > b`, the function returns `NaN`. * - If `a` or `b` is not an integer value, the function returns `NaN`. * * @param x - input value * @param a - minimum support * @param b - maximum support * @returns evaluated logCDF * * @example * var y = logcdf( 9.0, 0, 10 ); * // returns ~-0.095 * * @example * var y = logcdf( 0.5, 0, 2 ); * // returns ~-1.099 * * @example * var y = logcdf( +Infinity, 2, 4 ); * // returns 0.0 * * @example * var y = logcdf( -Infinity, 2, 4 ); * // returns -Infinity * * @example * var y = logcdf( NaN, 0, 1 ); * // returns NaN * * @example * var y = logcdf( 0.0, NaN, 1 ); * // returns NaN * * @example * var y = logcdf( 0.0, 0, NaN ); * // returns NaN * * @example * var y = logcdf( 2.0, 1, 0 ); * // returns NaN */ ( x: number, a: number, b: number ): number; /** * Returns a function for evaluating the natural logarithm of the cumulative distribution function (CDF) for a discrete uniform distribution with minimum support `a` and maximum support `b`. * * @param a - minimum support * @param b - maximum support * @returns logCDF * * @example * var mylogcdf = logcdf.factory( 0, 10 ); * var y = mylogcdf( 0.5 ); * // returns ~-2.398 * * y = mylogcdf( 8.0 ); * // returns ~-0.201 */ factory( a: number, b: number ): Unary; } /** * Discrete uniform distribution logarithm of cumulative distribution function (CDF). * * @param x - input value * @param a - minimum support * @param b - maximum support * @returns evaluated logCDF * * @example * var y = logcdf( 3.0, 0, 4 ); * // returns ~-0.223 * * var mylogcdf = logcdf.factory( 0, 10 ); * y = mylogcdf( 0.5 ); * // returns ~-2.398 * * y = mylogcdf( 8.0 ); * // returns ~-0.201 */ declare var logCDF: LogCDF; // EXPORTS // export = logCDF;