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sum () function in python

The sum of the numbers in the list is required everywhere. Python provides a built-in function sum () that sums the numbers in a list. 

Syntax:

  sum (iterable, start)   iterable:  iterable can be anything list, tuples or dictionaries, but most importantly it should be numbers.  start : this start is added to the sum of numbers in the iterable. If start is not given in the syntax, it is assumed to be 0. 

Two syntaxes are possible:

  sum (a)  a is the list, it adds up all the numbers in the list a and takes start to be 0, so returning only the sum of the numbers in the list.  sum (a, start)  this returns the sum of the list + start 

Below is the implementation of sum () in Python

# Python code to demonstrate how it works
# sum ()

 

numbers = [ 1 , 2 , 3 , 4 , 5 , 1 , 4 , 5 ]

 
< code class = "comments"> # no launch parameter specified

Sum = sum (numbers)

print ( Sum )

 
# start = 10

Sum = sum (numbers, 10 )

print ( Sum )

Output:

 25 35 

Errors and exceptions

error type: this error occurs if the list contains something other than digits.

# Python code to demonstrate the exception
# sum ()

arr = [ "a" ]

 
# no launch parameter specified

Sum = sum (arr)

print ( Sum )

 
# start = 10

Sum = sum (arr,  10 )

print ( Sum )

Runtime Error:

 Traceback (most recent call last): File "/home/23f0f6c9e022aa96d6c560a7eb4cf387.py" , line 6, in Sum = sum (arr) TypeError: unsupported operand type (s) for +: `int` and` str` 

So the list must contain numbers

Practical Application: problems when we need to calculate the amount to perform further operations, such as determining the average.

# Python code to demonstrate practical use
Amount # ()

  

nu mbers = [ 1 , 2 , 3 , 4 , 5 , 1 , 4 , 5 ]

 
# start = 10

Sum = sum (numbers)

average = Sum / len (numbers) 

p rint average

Output:

 3 
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