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@stdlib/math-base-special-factorialln

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Evaluate the natural logarithm of the factorial 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 natural logarithm of the factorial of `x`. * * @param x - input value * @returns natural logarithm of factorial of `x` * * @example * var v = factorialln( 3.0 ); * // returns ~1.792 * * @example * var v = factorialln( 2.4 ); * // returns ~1.092 * * @example * var v = factorialln( -1.0 ); * // returns NaN * * @example * var v = factorialln( -1.5 ); * // returns ~1.266 * * @example * var v = factorialln( NaN ); * // returns NaN */ declare function factorialln( x: number ): number; // EXPORTS // export = factorialln;