public void RotateY()
{
var rotMtx = Matrix3d.IDRotateY(Math.PI * 0.5); //rotate 90 degrees
var rotvec = rotMtx.Transform(testVectorX);
Assert.AreEqual(0, rotvec.X, 1.5e-15, "X should be 0, \r The vector is: " + rotvec);
Assert.AreEqual(0, rotvec.Y, 1.5e-15, "Y should be 0, \r The vector is: " + rotvec);
Assert.AreEqual(-testVectorX.X, rotvec.Z, 1.5e-15, "Z should be " + (-testVectorY.X) + ", \r The vector is: " + rotvec);
}