mirror of https://github.com/jkjoy/sunpeiwen.git
24 lines
739 B
JavaScript
24 lines
739 B
JavaScript
// 20.2.2.16 Math.fround(x)
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var sign = require('./_math-sign');
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var pow = Math.pow;
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var EPSILON = pow(2, -52);
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var EPSILON32 = pow(2, -23);
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var MAX32 = pow(2, 127) * (2 - EPSILON32);
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var MIN32 = pow(2, -126);
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var roundTiesToEven = function (n) {
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return n + 1 / EPSILON - 1 / EPSILON;
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};
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module.exports = Math.fround || function fround(x) {
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var $abs = Math.abs(x);
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var $sign = sign(x);
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var a, result;
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if ($abs < MIN32) return $sign * roundTiesToEven($abs / MIN32 / EPSILON32) * MIN32 * EPSILON32;
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a = (1 + EPSILON32 / EPSILON) * $abs;
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result = a - (a - $abs);
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// eslint-disable-next-line no-self-compare
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if (result > MAX32 || result != result) return $sign * Infinity;
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return $sign * result;
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};
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