13 lines
289 B
JavaScript
13 lines
289 B
JavaScript
"use strict";
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var log = Math.log, sqrt = Math.sqrt;
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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 0;
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if (value === Infinity) return value;
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return log(value + sqrt(value * value - 1));
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};
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