numpy.sum () in Python

numpy.sum (arr, axis, dtype, out) : This function returns the sum of the array elements along the specified axis.

Parameters:
arr: input array.
axis: axis along which we want to calculate the sum value. Otherwise, it will consider arr to be flattened (works on all the axis). axis = 0 means along the column and axis = 1 means working along the row.
out: Different array in which we want to place the result. The array must have same dimensions as expected output. Default is None.
initial: [scalar, optional] Starting value of the sum.

Return: Sum of the array elements ( a scalar value if axis is none) or array with sum values ​​along the specified axis.

Code # 1:

# Python program illustrating
# numpy.sum () method

import numpy as np 

 
# 1D array

arr = [ 20 , 2 ,. 2 , 10 , 4

  

print ( "Sum of arr : " , np. sum (arr)) 

 

print ( "Sum of arr (uint8):" , np. sum (arr, dtype = np.uint8)) 

print ( "Sum of arr (float32):" , np. sum (arr, dtype = np.float32))

  

print ( " Is np.sum (arr) .dtype == np.uint: "

  np. sum (arr) .dtype = = np.uint) 

 

print ( "Is np.sum (arr) .dtype == np.uint:"

np. sum (arr) .dtype = = np. float

Output:

 Sum of arr: 36.2 Sum of arr (uint8): 36 Sum of arr (float32): 36.2 Is np.sum (arr) .dtype == np.uint : False Is np.sum (arr) .dtype == np.uint: True 

Code # 2:

# Python program illustrating
# numpy.sum () method

import numpy as np 

 
# 2D array

arr = [[ 14 , 17 , 12 , 33 , 44 ], < / code>

[ 15 , 6 , 27 , 8 , 19 ], 

[ 23 , 2 , 54 , 1 , 4 ,]] 

 

print ( "Sum of arr:" , np. sum (arr)) 

< code class = "undefined spaces">  

print ( " Sum of arr (uint8): " , np. sum (arr, dtype = np.uint8)) 

print ( "Sum of arr (float32):" , np. sum (arr, dtype = np.float32))

 

print ( " Is np.sum (arr) .dtype == np.uint: "

np. sum (arr) .dtype = = np.uint) 

 

print ( "Is np.sum (arr) .dtype == np.uint:"

  np. sum (arr) .dtype = = np. float

Output:

 Sum of arr: 279 Sum of arr (uint8): 23 Sum of arr (float32): 279.0 Is np.sum (arr) .dtype == np.uint : False Is np.sum (arr) .dtype == np.uint: False 

Code # 3:

# Python program illustrating
# numpy.sum () method

 

import numpy as np 

  
# 2D array

arr = [[ 14 , 17 , 12 , 33 , 44 ] , 

[ 15 , 6 , 27 , 8 , 19 ], 

  [ 23 , 2 , 54 , 1 , 4 ,]] 

 

print ( "Sum of arr:" , np. sum (arr)) 

print ( "Sum of arr (axis = 0):" , np. sum (arr, axis = 0 )) 

print ( "Sum of arr (axis = 1):" , np. sum (arr, axis = 1 ))

 

print ( "Sum of arr (keepdimension is True):" ,

  np. sum (arr, axis = 1 , keepdims = True ))

Exit :

 Sum of arr: 279 Sum of arr (axis = 0) : [52 25 93 42 67] Sum of arr (axis = 1): [120 75 84] Sum of arr (keepdimension is True): [[120] [75] [84]]