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// Credit: https://github.com/paulmillr/es6-shim/
'use strict';
var pow = Math.pow;
module.exports = function (bytes, ebits, fbits) {
// Bytes to bits
var bits = [], i, j, b, str,
bias, s, e, f;
for (i = bytes.length; i; i -= 1) {
b = bytes[i - 1];
for (j = 8; j; j -= 1) {
bits.push(b % 2 ? 1 : 0);
b = b >> 1;
}
}
bits.reverse();
str = bits.join('');
// Unpack sign, exponent, fraction
bias = (1 << (ebits - 1)) - 1;
s = parseInt(str.substring(0, 1), 2) ? -1 : 1;
e = parseInt(str.substring(1, 1 + ebits), 2);
f = parseInt(str.substring(1 + ebits), 2);
// Produce number
if (e === (1 << ebits) - 1) return f !== 0 ? NaN : s * Infinity;
if (e > 0) return s * pow(2, e - bias) * (1 + f / pow(2, fbits));
if (f !== 0) return s * pow(2, -(bias - 1)) * (f / pow(2, fbits));
return s < 0 ? -0 : 0;
};
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