68 lines
1.3 KiB
JavaScript
68 lines
1.3 KiB
JavaScript
var math = require('./math');
|
|
|
|
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] ^= math.gexp(math.glog(this.get(i) ) + math.glog(e.get(j) ) );
|
|
}
|
|
}
|
|
|
|
return new QRPolynomial(num, 0);
|
|
},
|
|
|
|
mod : function(e) {
|
|
|
|
if (this.getLength() - e.getLength() < 0) {
|
|
return this;
|
|
}
|
|
|
|
var ratio = math.glog(this.get(0) ) - math.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 i = 0; i < e.getLength(); i++) {
|
|
num[i] ^= math.gexp(math.glog(e.get(i) ) + ratio);
|
|
}
|
|
|
|
// recursive call
|
|
return new QRPolynomial(num, 0).mod(e);
|
|
}
|
|
};
|
|
|
|
module.exports = QRPolynomial;
|