How to find the sum of all elements of a list or a Numpy array?

The numpy.sum() function calculates the sum of all the elements in a numpy array or list along a given axis.

Example

import numpy as np
arr = [5,2,6,21,63]
print("Our array: ", arr) 
print("Sum of array : ", np.sum(arr))

We can also calculate the sum across different axis such as rows or columns by specifying the axis parameter. Specifying axis = 0 means the sum will be calculated along the column and axis = 1 specifies to find the sum across the rows.

Example

import numpy as np  
  
arr = [[1, 17, 12, 12, 36],  
       [78, 16, 27, 70, 21], 
       [98, 45, 42, 11, 45, ]] 
     
# sum along the columns
print("sum of our array along the columns by setting axis = 0 : ", np.sum(arr, axis = 0)) 
   
# sum along the rows
print("sum  of our array along the rows by setting axis = 1 : ", np.sum(ar