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- '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);
- };
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