public static IComplexPolynomial GCD(IComplexPolynomial left, IComplexPolynomial right)
{
IComplexPolynomial a = left.Clone();
IComplexPolynomial b = right.Clone();
if (b.Degree > a.Degree)
{
IComplexPolynomial swap = b;
b = a;
a = swap;
}
while (!(b.Degree == 0 || (b.Terms[0].CoEfficient.Real == 1 && b.Terms[0].CoEfficient.Imaginary == 0)))
{
IComplexPolynomial temp = a.Clone();
a = b.Clone();
b = ComplexPolynomial.Mod(temp, b);
}
if (a.Degree == 0)
{
return(ComplexPolynomial.One);
}
else
{
return(a);
}
}
/*
* public static IPoly ExponentiateMod(IPoly startPoly, Complex s2, IPoly f, Complex p)
* {
* IPoly result = ComplexPoly.One;
* if (s2 == 0) { return result; }
*
* IPoly A = startPoly.Clone();
*
* byte[] byteArray = s2.ToByteArray();
* bool[] bitArray = new BitArray(byteArray).Cast<bool>().ToArray();
*
* // Remove trailing zeros ?
* if (bitArray[0] == true)
* {
* result = startPoly;
* }
*
* int i = 1;
* int t = bitArray.Length;
* while (i < t)
* {
* A = ComplexPoly.ModMod(ComplexPoly.Square(A), f, p);
* if (bitArray[i] == true)
* {
* result = ComplexPoly.ModMod(ComplexPoly.Multiply(A, result), f, p);
* }
* i++;
* }
*
* return result;
* }
*/
#endregion
public static IComplexPolynomial ModPow(IComplexPolynomial poly, Complex exponent, IComplexPolynomial modulus)
{
//if (exponent.Sign() == -1)
//{
// throw new NotImplementedException("Raising a polynomial to a negative exponent not supported. Build this functionality if it is needed.");
//}
if (exponent == Complex.Zero)
{
return(ComplexPolynomial.One);
}
else if (exponent == Complex.One)
{
return(poly.Clone());
}
else if (exponent == 2)
{
return(ComplexPolynomial.Square(poly));
}
IComplexPolynomial total = ComplexPolynomial.Square(poly);
Complex counter = exponent - 2;
while (counter != 0)
{
total = Multiply(poly, total);
if (total.CompareTo(modulus) < 0)
{
total = ComplexPolynomial.Mod(total, modulus);
}
counter -= 1;
}
return(total);
}
public static IComplexPolynomial ModMod(IComplexPolynomial toReduce, IComplexPolynomial modPoly, Complex modPrime)
{
return(ComplexPolynomial.Modulus(ComplexPolynomial.Mod(toReduce, modPoly), modPrime));
}
