@MathdudeMan thanks for your contribution.

I can see that you have changed the type of the input function in the constructor for the ParametricFunction class, so it will be function: Callable[[float | np.ndarray], Point3DLike].

Can you describe why the np.ndarray part was added to the type annotation?
On my computer it seems to work well with only the float part of the type annotation.

On line 168, that same self.function is called with a Numpy array rather than a float, thus the need for an extra type.

@MathdudeMan
Good catch, I missed that the class ParametricFunction also supported vectorized functions.
In that case I think that you need to do something like

def internal_parametric_function(
    t: float | np.ndarray,
) -> Point3D | Point3D_Array:

to specify that the output of the internal_parametric_function could be an array.

@chopan050 What is your take on this? To me it seems like MathdudeMan has found a potential typing issue that is not detected by mypy. I can follow his logic but I don't understand why mypy think it is ok.