<!-- @license Apache-2.0 Copyright (c) 2018 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. --> # xlog1py > Compute `x * ln(y+1)` so that the result is `0` if `x = 0`. <section class="usage"> ## Usage ```javascript var xlog1py = require( '@stdlib/math/base/special/xlog1py' ); ``` #### xlog1py( x, y ) Computes `x * ln(y+1)` so that the result is `0` if `x = 0`. ```javascript var out = xlog1py( 3.0, 2.0 ); // returns ~3.296 out = xlog1py( 1.5, 5.9 ); // returns ~2.897 out = xlog1py( 0.9, 1.0 ); // returns ~0.624 out = xlog1py( 1.0, 0.0 ); // returns 0.0 out = xlog1py( 0.0, -2.0 ); // returns 0.0 out = xlog1py( 1.5, NaN ); // returns NaN out = xlog1py( 0.0, NaN ); // returns NaN out = xlog1py( NaN, 2.3 ); // returns NaN ``` </section> <!-- /.usage --> <section class="examples"> ## Examples <!-- eslint no-undef: "error" --> ```javascript var randu = require( '@stdlib/random/base/randu' ); var xlog1py = require( '@stdlib/math/base/special/xlog1py' ); var x; var y; var i; for ( i = 0; i < 100; i++ ) { x = randu(); if ( x < 0.5 ) { x = 0.0; } y = ( randu() * 20.0 ) - 5.0; console.log( 'xlog1py(%d, %d) = %d', x, y, xlog1py( x, y ) ); } ``` </section> <!-- /.examples --> <section class="links"> </section> <!-- /.links -->