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18 lines
400 B
18 lines
400 B
6 years ago
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"use strict";
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var exp = Math.exp;
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module.exports = function (value) {
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var num1, num2;
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if (isNaN(value)) return NaN;
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value = Number(value);
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if (value === 0) return value;
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if (value === Infinity) return 1;
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if (value === -Infinity) return -1;
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num1 = exp(value);
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if (num1 === Infinity) return 1;
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num2 = exp(-value);
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if (num2 === Infinity) return -1;
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return (num1 - num2) / (num1 + num2);
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};
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