multiple conditions in numpy.where [duplicate]

Question

With some numpy array a, what I'd like to do is

indices = np.where((a < 4) or (a > 12))

This isn't valid. It just returns "The truth value of an array with more than one element is ambiguous. Use a.any() or a.all()". But this expression isn't ambiguous, and any and all don't do what I want to do. (any and all can't take compound expressions either. But if can. Confused...)

Answer 1

You want to get a logical/boolean array as your argument for where

You can do x | y or np.logical_or(x,y) , where x and y are a < 4 and a > 12