In [1]:

    

import numpy as np


    

In [2]:

    

a = np.array([10, 20, 30])


    

In [3]:

    

print(a)


    

    




[10 20 30]

In [4]:

    

print(np.diag(a))


    

    




[[10  0  0]
 [ 0 20  0]
 [ 0  0 30]]

In [5]:

    

print(np.diag([100, 200, 300]))


    

    




[[100   0   0]
 [  0 200   0]
 [  0   0 300]]

In [6]:

    

print(np.diag(a, k=1))


    

    




[[ 0 10  0  0]
 [ 0  0 20  0]
 [ 0  0  0 30]
 [ 0  0  0  0]]

In [7]:

    

print(np.diag(a, k=-2))


    

    




[[ 0  0  0  0  0]
 [ 0  0  0  0  0]
 [10  0  0  0  0]
 [ 0 20  0  0  0]
 [ 0  0 30  0  0]]

In [8]:

    

print(np.diag([1, 1, 1]))


    

    




[[1 0 0]
 [0 1 0]
 [0 0 1]]

In [9]:

    

print(np.identity(3))


    

    




[[1. 0. 0.]
 [0. 1. 0.]
 [0. 0. 1.]]

In [10]:

    

print(np.identity(3, int))


    

    




[[1 0 0]
 [0 1 0]
 [0 0 1]]