# Python sum()

Published on August 3, 2022 By Pankaj
Developer and author at DigitalOcean. While we believe that this content benefits our community, we have not yet thoroughly reviewed it. If you have any suggestions for improvements, please let us know by clicking the “report an issue“ button at the bottom of the tutorial.

Python sum() function is used to get the sum of numbers of an iterable.

## Python sum()

Python sum() function syntax is:

``````sum(iterable[, start])
``````

start is an optional number with default value of 0. If start is provided, then the sum of start and all the numbers in the iterable is returned.

## Python sum() list of numbers

``````s = sum([1, 2, 3])
print(s)

s = sum([1, 2, 3], 10)
print(s)
``````

Output:

``````6
16
``````

Note that sum() method doesn’t take keyword arguments, so if we write `sum([1, 2, 3], start=10)` then it will throw exception as `TypeError: sum() takes no keyword arguments`.

## Python sum of a sequence of integers

Since sum accepts iterable as argument, we can pass tuple, bytes of numbers too.

``````s = sum(bytes([1, 2]))
print(s)

s = sum(bytearray([1, 2]), 10)
print(s)

# sum of integers in different formats, tuple of numbers
s = sum((1, 0b11, 0o17, 0xFF))
print(s)

s = sum((1, 0b11, 0o17, 0xFF), 0xF)
print(s)
``````

Output:

``````3
13
274
289
``````

## Python sum of floats

``````s = sum([1.5, 2.5, 3])
print(s)
``````

Output: `7.0` If you want to add floating point values with extended precision, you can use `math.fsum()` function.

## Python sum of complex numbers

sum() function works with complex numbers too.

``````s = sum([1 + 2j, 3 + 4j])
print(s)

s = sum([1 + 2j, 3 + 4j], 2 + 2j)
print(s)

s = sum([1 + 2j, 2, 1.5 - 2j])
print(s)
``````

Output:

``````(4+6j)
(6+8j)
(4.5+0j)
``````

You can checkout complete python script and more Python examples from our GitHub Repository.

Reference: Official Documentation Pankaj

author

Developer and author at DigitalOcean.