public static bool secp256k1_ge_set_xo_var(Ge r, Fe x, bool odd) { if (!Group.secp256k1_ge_set_xquad(r, x)) { return(false); } Field.NormalizeVar(r.Y); if (Field.IsOdd(r.Y) != odd) { Field.Negate(r.Y, r.Y, 1U); } return(true); }