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- "use strict";
- Object.defineProperty(exports, "__esModule", {
- value: true
- });
- exports.read = read;
- exports.write = write;
- function read(buffer, offset, isLE, mLen, nBytes) {
- var e, m;
- var eLen = nBytes * 8 - mLen - 1;
- var eMax = (1 << eLen) - 1;
- var eBias = eMax >> 1;
- var nBits = -7;
- var i = isLE ? nBytes - 1 : 0;
- var d = isLE ? -1 : 1;
- var s = buffer[offset + i];
- i += d;
- e = s & (1 << -nBits) - 1;
- s >>= -nBits;
- nBits += eLen;
- for (; nBits > 0; e = e * 256 + buffer[offset + i], i += d, nBits -= 8) {}
- m = e & (1 << -nBits) - 1;
- e >>= -nBits;
- nBits += mLen;
- for (; nBits > 0; m = m * 256 + buffer[offset + i], i += d, nBits -= 8) {}
- if (e === 0) {
- e = 1 - eBias;
- } else if (e === eMax) {
- return m ? NaN : (s ? -1 : 1) * Infinity;
- } else {
- m = m + Math.pow(2, mLen);
- e = e - eBias;
- }
- return (s ? -1 : 1) * m * Math.pow(2, e - mLen);
- }
- function write(buffer, value, offset, isLE, mLen, nBytes) {
- var e, m, c;
- var eLen = nBytes * 8 - mLen - 1;
- var eMax = (1 << eLen) - 1;
- var eBias = eMax >> 1;
- var rt = mLen === 23 ? Math.pow(2, -24) - Math.pow(2, -77) : 0;
- var i = isLE ? 0 : nBytes - 1;
- var d = isLE ? 1 : -1;
- var s = value < 0 || value === 0 && 1 / value < 0 ? 1 : 0;
- value = Math.abs(value);
- if (isNaN(value) || value === Infinity) {
- m = isNaN(value) ? 1 : 0;
- e = eMax;
- } else {
- e = Math.floor(Math.log(value) / Math.LN2);
- if (value * (c = Math.pow(2, -e)) < 1) {
- e--;
- c *= 2;
- }
- if (e + eBias >= 1) {
- value += rt / c;
- } else {
- value += rt * Math.pow(2, 1 - eBias);
- }
- if (value * c >= 2) {
- e++;
- c /= 2;
- }
- if (e + eBias >= eMax) {
- m = 0;
- e = eMax;
- } else if (e + eBias >= 1) {
- m = (value * c - 1) * Math.pow(2, mLen);
- e = e + eBias;
- } else {
- m = value * Math.pow(2, eBias - 1) * Math.pow(2, mLen);
- e = 0;
- }
- }
- for (; mLen >= 8; buffer[offset + i] = m & 0xff, i += d, m /= 256, mLen -= 8) {}
- e = e << mLen | m;
- eLen += mLen;
- for (; eLen > 0; buffer[offset + i] = e & 0xff, i += d, e /= 256, eLen -= 8) {}
- buffer[offset + i - d] |= s * 128;
- }
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