find_length for window length only works for 1D data

[Blackandwhite23]

It seems to me, that the function "find_length" only works, when the data is one dimensional. If this is on purpose it would be nice to mention it in the docu.

def find_length(data):
if len(data.shape)>1:
return 0

[lcxyxz]

Is the time complexity too high?