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-rw-r--r--node_modules/es5-ext/math/_pack-ieee754.js88
1 files changed, 88 insertions, 0 deletions
diff --git a/node_modules/es5-ext/math/_pack-ieee754.js b/node_modules/es5-ext/math/_pack-ieee754.js
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+/* eslint no-bitwise: "off" */
+// Credit: https://github.com/paulmillr/es6-shim/
+
+"use strict";
+
+var abs = Math.abs
+ , floor = Math.floor
+ , log = Math.log
+ , min = Math.min
+ , pow = Math.pow
+ , LN2 = Math.LN2
+ , roundToEven;
+
+roundToEven = function (num) {
+ var whole = floor(num), fraction = num - whole;
+ if (fraction < 0.5) return whole;
+ if (fraction > 0.5) return whole + 1;
+ return whole % 2 ? whole + 1 : whole;
+};
+
+// eslint-disable-next-line max-statements
+module.exports = function (value, ebits, fbits) {
+ var bias = (1 << (ebits - 1)) - 1, sign, e, fraction, i, bits, str, bytes;
+
+ // Compute sign, exponent, fraction
+ if (isNaN(value)) {
+ // NaN
+ // http://dev.w3.org/2006/webapi/WebIDL/#es-type-mapping
+ e = (1 << ebits) - 1;
+ fraction = pow(2, fbits - 1);
+ sign = 0;
+ } else if (value === Infinity || value === -Infinity) {
+ e = (1 << ebits) - 1;
+ fraction = 0;
+ sign = value < 0 ? 1 : 0;
+ } else if (value === 0) {
+ e = 0;
+ fraction = 0;
+ sign = 1 / value === -Infinity ? 1 : 0;
+ } else {
+ sign = value < 0;
+ value = abs(value);
+
+ if (value >= pow(2, 1 - bias)) {
+ e = min(floor(log(value) / LN2), 1023);
+ fraction = roundToEven(value / pow(2, e) * pow(2, fbits));
+ if (fraction / pow(2, fbits) >= 2) {
+ e += 1;
+ fraction = 1;
+ }
+ if (e > bias) {
+ // Overflow
+ e = (1 << ebits) - 1;
+ fraction = 0;
+ } else {
+ // Normal
+ e += bias;
+ fraction -= pow(2, fbits);
+ }
+ } else {
+ // Subnormal
+ e = 0;
+ fraction = roundToEven(value / pow(2, 1 - bias - fbits));
+ }
+ }
+
+ // Pack sign, exponent, fraction
+ bits = [];
+ for (i = fbits; i; i -= 1) {
+ bits.push(fraction % 2 ? 1 : 0);
+ fraction = floor(fraction / 2);
+ }
+ for (i = ebits; i; i -= 1) {
+ bits.push(e % 2 ? 1 : 0);
+ e = floor(e / 2);
+ }
+ bits.push(sign ? 1 : 0);
+ bits.reverse();
+ str = bits.join("");
+
+ // Bits to bytes
+ bytes = [];
+ while (str.length) {
+ bytes.push(parseInt(str.substring(0, 8), 2));
+ str = str.substring(8);
+ }
+ return bytes;
+};