@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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TypeScript
/*
* @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;