fromulabimportnumpyasnpa=np.array(range(8))print(np.where(a<4,1,0))print(np.where(a<4,2*a,0))a=np.array(range(12)).reshape((3,4))print(np.where(a<6,a,-1))b=np.array(range(4))print(np.where(a<6,10+b,-1))# test upcasting hereb=np.array(range(4),dtype=np.uint8)c=np.array([25,25,25,25],dtype=np.int16)print(np.where(a<6,b,c))