How to separate coordinates in a numpy array belonging to different quadrant?

Question

I have a NumPy array containing small arrays of [x,y] coordinate. I want to separate the coordinates belonging to different quadrants.I have tried to use NumPy.where like this:

 row,col=np.where(sort_list[0]>0 and sort_list[1]>0)
    postive_values=sort_list[row,col]

row,col=np.where(sort_list[0]<0 and sort_list[1]<0)
        negetive_values=sort_list[row,col]

However, I get an error as follows:

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

How do I do this?