18 lines
445 B
JavaScript
18 lines
445 B
JavaScript
// Thanks: https://github.com/monolithed/ECMAScript-6/blob/master/ES6.js
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"use strict";
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var log = Math.log;
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module.exports = function (value) {
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if (isNaN(value)) return NaN;
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value = Number(value);
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if (value < -1) return NaN;
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if (value === -1) return -Infinity;
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if (value === 0) return value;
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if (value === Infinity) return Infinity;
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if (value > -1.0e-8 && value < 1.0e-8) return value - (value * value) / 2;
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return log(1 + value);
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};
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