15 lines
313 B
JavaScript
15 lines
313 B
JavaScript
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"use strict";
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var log = Math.log, LOG2E = Math.LOG2E;
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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 < 0) return NaN;
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if (value === 0) return -Infinity;
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if (value === 1) return 0;
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if (value === Infinity) return Infinity;
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return log(value) * LOG2E;
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};
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