private void DivTest()
{
Random rng = new Random();
for (int i = 0; i < 10; i++)
{
IntegerPolynomial poly = (IntegerPolynomial)PolynomialGeneratorForTesting.GenerateRandom(439, 10000);
// test special case: division by 2048
IntegerPolynomial a = poly.Clone();
a.Divide(2048);
for (int j = 0; j < poly.Coeffs.Length; j++)
{
if (!Compare.Equals((int)Math.Floor((((double)poly.Coeffs[j]) / 2048) + 0.5), a.Coeffs[j]))
{
throw new Exception("IntegerPolynomialTest division test failed!");
}
}
// test the general case
a = poly.Clone();
int k = rng.Next(2047) + 1;
a.Divide(k);
for (int j = 0; j < poly.Coeffs.Length; j++)
{
if (!Compare.Equals((int)Math.Floor(((double)poly.Coeffs[j] / k) + 0.5), a.Coeffs[j]))
{
throw new Exception("IntegerPolynomialTest division test failed!");
}
}
}
}
private IntegerPolynomial sign(IntegerPolynomial i, SignatureKeyPair kp)
{
int N = param.N;
int q = param.q;
int perturbationBases = param.B;
IntegerPolynomial s = new IntegerPolynomial(N);
int iLoop = perturbationBases;
while (iLoop >= 1)
{
IPolynomial f = kp.priv.getBasis(iLoop).f;
IPolynomial fPrime = kp.priv.getBasis(iLoop).fPrime;
IntegerPolynomial y = f.Multiply(i);
y.Divide(q);
y = fPrime.Multiply(y);
IntegerPolynomial x = fPrime.Multiply(i);
x.Divide(q);
x = f.Multiply(x);
IntegerPolynomial si = y;
si.Subtract(x);
s.Add(si);
IntegerPolynomial hi = kp.priv.getBasis(iLoop).h.Clone();
if (iLoop > 1)
{
hi.Subtract(kp.priv.getBasis(iLoop - 1).h);
}
else
{
hi.Subtract(kp.pub.h);
}
i = si.Multiply(hi, q);
iLoop--;
}
IPolynomial f2 = kp.priv.getBasis(0).f;
IPolynomial fPrime2 = kp.priv.getBasis(0).fPrime;
IntegerPolynomial y2 = f2.Multiply(i);
y2.Divide(q);
y2 = fPrime2.Multiply(y2);
IntegerPolynomial x2 = fPrime2.Multiply(i);
x2.Divide(q);
x2 = f2.Multiply(x2);
y2.Subtract(x2);
s.Add(y2);
s.ModPositive(q);
return(s);
}
