Innovenergy_trunk/frontend/node_modules/qrcode-terminal/vendor/QRCode/QRPolynomial.js

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var QRMath = require('./QRMath');
function QRPolynomial(num, shift) {
if (num.length === undefined) {
throw new Error(num.length + "/" + shift);
}
var offset = 0;
while (offset < num.length && num[offset] === 0) {
offset++;
}
this.num = new Array(num.length - offset + shift);
for (var i = 0; i < num.length - offset; i++) {
this.num[i] = num[i + offset];
}
}
QRPolynomial.prototype = {
get : function(index) {
return this.num[index];
},
getLength : function() {
return this.num.length;
},
multiply : function(e) {
var num = new Array(this.getLength() + e.getLength() - 1);
for (var i = 0; i < this.getLength(); i++) {
for (var j = 0; j < e.getLength(); j++) {
num[i + j] ^= QRMath.gexp(QRMath.glog(this.get(i) ) + QRMath.glog(e.get(j) ) );
}
}
return new QRPolynomial(num, 0);
},
mod : function(e) {
if (this.getLength() - e.getLength() < 0) {
return this;
}
var ratio = QRMath.glog(this.get(0) ) - QRMath.glog(e.get(0) );
var num = new Array(this.getLength() );
for (var i = 0; i < this.getLength(); i++) {
num[i] = this.get(i);
}
for (var x = 0; x < e.getLength(); x++) {
num[x] ^= QRMath.gexp(QRMath.glog(e.get(x) ) + ratio);
}
// recursive call
return new QRPolynomial(num, 0).mod(e);
}
};
module.exports = QRPolynomial;