[PYTHON] A memo explaining the axis specification of axis

a = np.array([
   [1, 1, 1],
   [1, 0, 1],
   [1, 0, 0],
   ])


print(np.all(a, axis=0)) #Row direction(From line 1 to line m)To see
print(np.all(a, axis=1)) #Column direction(From the 1st column to the nth column)
)To see

print(a)
a[2,0] = 0

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

>>> [ True False False]
>>> [ True False False]
>>> 
[[1 1 1]
 [1 0 1]
 [1 0 0]]
>>> [False False False] #From line 1 to line m
Look at True,False has been decided
>>> [ True False False] #From the 1st column to the nth column
Look at True,False has been decided

a = np.array([[1,2,3],
             [4,5,6]])
print(a)
np.sum(a, axis=0)
np.sum(a, axis=1)

>>> [[1 2 3]
 [4 5 6]]
>>> array([5, 7, 9]) #It is added along the 1st line to the mth line
>>> array([ 6, 15]) #It is added along the 1st to nth columns

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