What is sum () sum () in python?

❮ Built-in Functions


Example

Add all items in a tuple, and return the result:

a = (1, 2, 3, 4, 5)
x = sum(a)

Try it Yourself »


Definition and Usage

The sum() function returns a number, the sum of all items in an iterable.


Syntax

Parameter Values

ParameterDescription
iterable Required. The sequence to sum
start Optional. A value that is added to the return value

More Examples

Example

Start with the number 7, and add all the items in a tuple to this number:

a = (1, 2, 3, 4, 5)
x = sum(a, 7)

Try it Yourself »


❮ Built-in Functions


The sum() function adds the items of an iterable and returns the sum.

Example

marks = [65, 71, 68, 74, 61]

# find sum of all marks total_marks = sum(marks)

print(total_marks) # Output: 339


sum() Syntax

The syntax of the sum() function is:

sum(iterable, start)

The sum() function adds start and items of the given iterable from left to right.


sum() Parameters

  • iterable - iterable (list, tuple, dict, etc). The items of the iterable should be numbers.
  • start (optional) - this value is added to the sum of items of the iterable. The default value of start is 0 (if omitted)

sum() Return Value

sum() returns the sum of start and items of the given iterable.


Example: Working of Python sum()

numbers = [2.5, 3, 4, -5]

# start parameter is not provided

numbers_sum = sum(numbers)

print(numbers_sum) # start = 10

numbers_sum = sum(numbers, 10)

print(numbers_sum)

Output

4.5
14.5

If you need to add floating-point numbers with exact precision, then you should use math.fsum(iterable) instead.

If you need to concatenate items of the given iterable (items must be strings), then you can use the join() method.

'string'.join(sequence)

Visit this page to learn about, Python join() Method

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    Sum of numbers in the list is required everywhere. Python provides 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:

    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() 

    Python3

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

    Sum = sum(numbers)

    print(Sum)

    Sum = sum(numbers, 10)

    print(Sum)

    Output:

    25
    35

    Error and Exceptions

    TypeError : This error is raised in the case when there is anything other than numbers in the list. 

    Python3

    arr = ["a"]

    Sum = sum(arr)

    print(Sum)

    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'

    What is sum () sum () in python?
    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. 

    Python3

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

    Sum = sum(numbers)

    average= Sum/len(numbers)

    print (average)

    Output:

    3

    What is sum () in Python?

    Python sum() Function The sum() function returns a number, the sum of all items in an iterable.

    How do you write a sum function in Python?

    The sum() function is used to get the sum of all items in an iterable..
    Version: ... .
    Syntax: sum(iterable[, start]).
    Parameter: ... .
    Return value: ... .
    Example: Python sum() num = [3.5, 5, 2, -5] # start parameter is not provided numSum = sum(num) print(numSum) # start = 15 numSum = sum(num, 15) print(numSum) ... .
    Pictorial Presentation:.

    Does sum return an int Python?

    Returns an integer indicating the total of all values of the iterable.

    What is sum of series in Python?

    n=int(input("Enter the number of terms:")) x=int(input("Enter the value of x:")) sum1=1 for i in range(2,n+1): sum1=sum1+((x**i)/i) print("The sum of series is",round(sum1,2))