import numpy as np

print(np.subtract.outer(np.array([1,2]),np.array([1,3])))

print(np.outer(1,1))

print(np.zeros((1,1)))

print(np.array([1,2]).size)

print(np.array([1,2,5])[[0,2]])
import numpy as np

print(np.subtract.outer(np.array([1,2]),np.array([1,3])))

print(np.outer(1,1))

print(np.zeros((1,1)))

print(np.array([1,2]).size)

print(np.array([1,2,5])[[0,2]])