All files / math/base/special/powf/lib x_is_zerof.js

100% Statements 106/106
100% Branches 14/14
100% Functions 1/1
100% Lines 106/106

Press n or j to go to the next uncovered block, b, p or k for the previous block.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 1072x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 2x 447x 447x 2x 2x 447x 2x 2x 447x 236x 106x 106x 130x 130x 207x 447x 104x 104x 103x 447x 2x 2x 2x 2x 2x  
/**
* @license Apache-2.0
*
* Copyright (c) 2025 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.
*
*
* ## Notice
*
* The following copyright and license were part of the original implementation available as part of [FreeBSD]{@link https://svnweb.freebsd.org/base/release/9.3.0/lib/msun/src/s_pow.c}. The implementation follows the original, but has been modified for JavaScript.
*
* ```text
* Copyright (C) 2004 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ```
*/
 
'use strict';
 
// MODULES //
 
var isOddf = require( '@stdlib/math/base/assert/is-oddf' );
var copysignf = require( '@stdlib/math/base/special/copysignf' );
var f32 = require( '@stdlib/number/float64/base/to-float32' );
var NINF = require( '@stdlib/constants/float32/ninf' );
var PINF = require( '@stdlib/constants/float32/pinf' );
 
 
// VARIABLES //
 
var ZERO = f32( 0.0 );
 
 
// MAIN //
 
/**
* Evaluates the exponential function when \\(|x| = 0\\).
*
* @private
* @param {number} x - base
* @param {number} y - exponent
* @returns {number} function value
*
* @example
* var v = powf( 0.0, 2 );
* // returns 0.0
*
* @example
* var v = powf( -0.0, -9 );
* // returns -Infinity
*
* @example
* var v = powf( 0.0, -9 );
* // returns Infinity
*
* @example
* var v = powf( -0.0, 9 );
* // returns 0.0
*
* @example
* var v = powf( 0.0, -Infinity  );
* // returns Infinity
*
* @example
* var v = powf( 0.0, Infinity );
* // returns 0.0
*/
function powf( x, y ) {
	if ( y === NINF ) {
		return PINF;
	}
	if ( y === PINF ) {
		return ZERO;
	}
	if ( y > ZERO ) {
		if ( isOddf( y ) ) {
			return x; // handles +-0
		}
		return ZERO;
	}
	// y < 0.0
	if ( isOddf( y ) ) {
		return copysignf( PINF, x ); // handles +-0
	}
	return PINF;
}
 
 
// EXPORTS //
 
module.exports = powf;