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.

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.

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

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.

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