97 lines
1.7 KiB
Markdown
97 lines
1.7 KiB
Markdown
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@license Apache-2.0
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Copyright (c) 2018 The Stdlib Authors.
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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-->
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# xlogy
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> Compute `x * ln(y)` so that the result is `0` if `x = 0`.
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<section class="usage">
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## Usage
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```javascript
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var xlogy = require( '@stdlib/math/base/special/xlogy' );
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```
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#### xlogy( x, y )
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Computes `x * ln(y)` so that the result is `0` if `x = 0`.
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```javascript
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var out = xlogy( 3.0, 2.0 );
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// returns ~2.079
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out = xlogy( 1.5, 5.9 );
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// returns ~2.662
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out = xlogy( 0.9, 1.0 );
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// returns 0.0
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out = xlogy( 0.0, -2.0 );
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// returns 0.0
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out = xlogy( 1.5, NaN );
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// returns NaN
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out = xlogy( 0.0, NaN );
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// returns NaN
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out = xlogy( NaN, 2.3 );
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// returns NaN
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```
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</section>
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<!-- /.usage -->
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<section class="examples">
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## Examples
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<!-- eslint no-undef: "error" -->
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```javascript
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var randu = require( '@stdlib/random/base/randu' );
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var xlogy = require( '@stdlib/math/base/special/xlogy' );
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var x;
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var y;
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var i;
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for ( i = 0; i < 100; i++ ) {
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x = randu();
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if ( x < 0.5 ) {
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x = 0.0;
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}
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y = ( randu() * 20.0 ) - 5.0;
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console.log( 'xlogy(%d, %d) = %d', x, y, xlogy( x, y ) );
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}
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```
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</section>
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<!-- /.examples -->
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<section class="links">
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</section>
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<!-- /.links -->
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