/* set this=-this */
public void neg()
{
if (is_infinity())
{
return;
}
y.neg();
y.reduce();
return;
}
/* Calculate RHS of twisted curve equation x^3+B/i */
public static FP2 RHS(FP2 x)
{
x.norm();
FP2 r = new FP2(x);
r.sqr();
FP2 b = new FP2(new BIG(ROM.CURVE_B));
b.div_ip();
r.mul(x);
r.add(b);
r.reduce();
return(r);
}
/* set this*=q, where q is Modulus, using Frobenius */
public void frob(FP2 X)
{
if (INF)
{
return;
}
FP2 X2 = new FP2(X);
X2.sqr();
x.conj();
y.conj();
z.conj();
z.reduce();
x.mul(X2);
y.mul(X2);
y.mul(X);
}
/* set to Affine - (x,y,z) to (x,y) */
public void affine()
{
if (is_infinity())
{
return;
}
FP2 one = new FP2(1);
if (z.Equals(one))
{
return;
}
z.inverse();
FP2 z2 = new FP2(z);
z2.sqr();
x.mul(z2);
x.reduce();
y.mul(z2);
y.mul(z);
y.reduce();
z.copy(one);
}
/* reduce all components of this mod Modulus */
public void reduce()
{
a.reduce();
b.reduce();
}