public void PlaneAngleToPlaneTest2()
{
Point3d p1 = new Point3d(1, 0, 0);
Vector3d v1 = new Vector3d(0, 1, 1);
Plane3d s1 = new Plane3d(p1, v1);
Matrix3d m = Matrix3d.RotationMatrix(new Vector3d(0, -1, 1), 10 * PI / 180);
v1 = m * v1;
Plane3d s2 = new Plane3d(p1, -v1);
Assert.IsTrue(Abs(s1.AngleToDeg(s2) - 10) < GeometRi3D.Tolerance);
}