lix-website/themes/lix/assets/bootstrap/node_modules/es-abstract/helpers/bytesAsFloat32.js

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2024-04-27 03:39:10 +00:00
'use strict';
var GetIntrinsic = require('get-intrinsic');
var $pow = GetIntrinsic('%Math.pow%');
module.exports = function bytesAsFloat32(rawBytes) {
// return new $Float32Array(new $Uint8Array(rawBytes).buffer)[0];
/*
Let value be the byte elements of rawBytes concatenated and interpreted as a little-endian bit string encoding of an IEEE 754-2008 binary32 value.
If value is an IEEE 754-2008 binary32 NaN value, return the NaN Number value.
Return the Number value that corresponds to value.
*/
var sign = rawBytes[3] & 0x80 ? -1 : 1; // Check the sign bit
var exponent = ((rawBytes[3] & 0x7F) << 1)
| (rawBytes[2] >> 7); // Combine bits for exponent
var mantissa = ((rawBytes[2] & 0x7F) << 16)
| (rawBytes[1] << 8)
| rawBytes[0]; // Combine bits for mantissa
if (exponent === 0 && mantissa === 0) {
return sign === 1 ? 0 : -0;
}
if (exponent === 0xFF && mantissa === 0) {
return sign === 1 ? Infinity : -Infinity;
}
if (exponent === 0xFF && mantissa !== 0) {
return NaN;
}
exponent -= 127; // subtract the bias
if (exponent === -127) {
return sign * mantissa * $pow(2, -126 - 23);
}
return sign * (1 + (mantissa * $pow(2, -23))) * $pow(2, exponent);
};