Error when intializing FAMC filter without acc or mag samples.

[osskov]

Minor bug but when initializing an FAMC filter with no acc or mag entry, it throws: AttributeError: 'NoneType' object has no attribute 'copy'

Here is the version of the initialization call in the package: class FAMC: def init(self, acc: np.ndarray = None, mag: np.ndarray = None): self.acc = acc.copy() self.mag = mag.copy() self.Q = None if self.acc is not None and self.mag is not None: self.Q = self._compute_all()