sum() function in Python
Sum of numbers in the list is required everywhere. Python provide an inbuilt function sum() which sums up the numbers in the 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.
Possible two syntaxes:
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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 Python implementation of the sum()
# Python code to demonstrate the working of # sum() numbers = [1,2,3,4,5,1,4,5] # start parameter is not providedSum = sum(numbers)print(Sum) # start = 10Sum = sum(numbers, 10)print(Sum) |
Output:
25 35
Error and Exceptions
TypeError : This error is raised in the case when there is anything other then numbers in the list.
# Python code to demonstrate the exception of # sum()arr = ["a"] # start parameter is not providedSum = sum(arr)print(Sum) # start = 10Sum = 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 should contain numbers
Practical Application: Problems where we require sum to be calculated to do further operations such as finding out the average of numbers.
# Python code to demonstrate the practical application# of sum() numbers = [1,2,3,4,5,1,4,5] # start = 10Sum = sum(numbers)average= Sum/len(numbers) print (average) |
Output:
3
