In [1]:

    

import numpy as np


    

In [2]:

    

a = np.arange(12).reshape(3, 4)
print(a.shape)
print(a)


    

    




(3, 4)
[[ 0  1  2  3]
 [ 4  5  6  7]
 [ 8  9 10 11]]

In [3]:

    

print(np.sum(a))


    

    




66

In [4]:

    

print(np.sum(a, axis=0))
print(np.sum(a, axis=1))


    

    




[12 15 18 21]
[ 6 22 38]

In [5]:

    

print(a.sum())


    

    




66

In [6]:

    

print(a.sum(axis=0))
print(a.sum(axis=1))


    

    




[12 15 18 21]
[ 6 22 38]

In [7]:

    

print(np.mean(a))


    

    




5.5

In [8]:

    

print(np.mean(a, axis=0))
print(np.mean(a, axis=1))


    

    




[ 4.  5.  6.  7.]
[ 1.5  5.5  9.5]

In [9]:

    

print(a.mean())


    

    




5.5

In [10]:

    

print(a.mean(axis=0))
print(a.mean(axis=1))


    

    




[ 4.  5.  6.  7.]
[ 1.5  5.5  9.5]

In [11]:

    

print(np.min(a))
print(np.min(a, axis=0))


    

    




0
[0 1 2 3]

In [12]:

    

print(a.max())
print(a.max(axis=1))


    

    




11
[ 3  7 11]

In [13]:

    

b = np.arange(24).reshape(2, 3, 4)
print(b.shape)
print(b)


    

    




(2, 3, 4)
[[[ 0  1  2  3]
  [ 4  5  6  7]
  [ 8  9 10 11]]

 [[12 13 14 15]
  [16 17 18 19]
  [20 21 22 23]]]

In [14]:

    

print(b.sum(axis=0))


    

    




[[12 14 16 18]
 [20 22 24 26]
 [28 30 32 34]]

In [15]:

    

print(b[0, :, :] + b[1, :, :])


    

    




[[12 14 16 18]
 [20 22 24 26]
 [28 30 32 34]]

In [16]:

    

print(b.sum(axis=1))


    

    




[[12 15 18 21]
 [48 51 54 57]]

In [17]:

    

print(b[:, 0, :] + b[:, 1, :] + b[:, 2, :])


    

    




[[12 15 18 21]
 [48 51 54 57]]

In [18]:

    

print(b.sum(axis=2))


    

    




[[ 6 22 38]
 [54 70 86]]

In [19]:

    

print(b[:, :, 0] + b[:, :, 1] + b[:, :, 2] + b[:, :, 3])


    

    




[[ 6 22 38]
 [54 70 86]]

In [20]:

    

print(b.sum(axis=(0, 1)))


    

    




[60 66 72 78]

In [21]:

    

print(b.sum(axis=(0, 2)))


    

    




[ 60  92 124]

In [22]:

    

print(b.sum(axis=(1, 2)))


    

    




[ 66 210]