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- 'use strict';
- var GetIntrinsic = require('get-intrinsic');
- var $pow = GetIntrinsic('%Math.pow%');
- module.exports = function bytesAsFloat32(rawBytes) {
-
-
- var sign = rawBytes[3] & 0x80 ? -1 : 1;
- var exponent = ((rawBytes[3] & 0x7F) << 1)
- | (rawBytes[2] >> 7);
- var mantissa = ((rawBytes[2] & 0x7F) << 16)
- | (rawBytes[1] << 8)
- | rawBytes[0];
- 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;
- if (exponent === -127) {
- return sign * mantissa * $pow(2, -126 - 23);
- }
- return sign * (1 + (mantissa * $pow(2, -23))) * $pow(2, exponent);
- };
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