Providing Data classes with numpy arrays throws ValueError

Created by: tsampazk

For example in Vector, the following code snippet throws ValueError from constructor:

vec = np.array([0 for _ in range(100)])
openDRVector= Vector(vec)

ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.all()

Numpy arrays can't be used in ctor as if data: ... We can't expect users to only provide python lists.

Fix: conditional needs to change to if data is not None: that i think covers all cases.