How to create a function of n variables (python)

Question

I would like to create a function of n variables in python, such as

n=3
def func(n1,n2,n3):
    return sum(n1+n2+n3)

func(1,2,3) = 6
func(3,3,3)=9

or if n=4,

n=4
def func(n1,n2,n3,n4):
    return sum(n1+n2+n3+n4)

func(1,2,3,4) = 10

There is a perfect example of someone doing this in julia: How to create a function of n variables (Julia)

using this solution

function f(x...)
     sum(x)
end

julia> f(1,2,3)
6

However I do not know how to translate the ellipses type input to python

the `args` keyword is used in Python, see [can-a-variable-number-of-arguments-be-passed-to-a-function](https://stackoverflow.com/questions/919680/can-a-variable-number-of-arguments-be-passed-to-a-function). — Krishna Chaurasia, Mar 04 '21 at 09:08
@KrishnaChaurasia, `args` is not a keyword - it's a regular name of the argument — ForceBru, Mar 04 '21 at 09:12

score 1 · Accepted Answer · answered Mar 04 '21 at 09:08

Python supports variable arguments too

def f(*x):
    return sum(x)

The x inside the function will also be a tuple, like in Julia.

Julia:

julia> function f(x...)
        x
       end

f (generic function with 1 method)

julia> f(2,4,5)
(2, 4, 5)

Python:

>>> def f(*x):
...  return x
... 
>>> f(2,4,5)
(2, 4, 5)

Daweo · Answer 2 · 2021-03-04T09:10:50.017

0

Use unpacking operator (*):

def func(*x):
    return sum(x)

Note that when using this notation x is tuple inside func, which sum happilly accepts.

edited Mar 04 '21 at 09:10

answered Mar 04 '21 at 09:08

Daweo

1

You actually aren't using the unpacking operator. – CryptoFool Mar 04 '21 at 09:12

2 Answers2