How do I pass a array/list to python if I know exactly how big it is going to be?-CodePudding

I have this code and it works and I can continue on with this so this is an efficiency question. I want to pass an array into this function and I know each time it is going to be 3x1. This works but I wondering I could save computation time if I could specify the size. I tried saying def FUNC(p0=[3]): but it does not work.

def FUNC(p0=[]):

    print(p0[1])
    pass

FUNC([1,1,2])

CodePudding user response：

One way is just to use three distinct variables, and unpack the list while calling the function, but I'm not sure about the efficiency:

def fn(x,y,z):
    print(x,y,z)

fn(*[2,3,4])
2 3 4

But it's also certain that there is no any other way to limit the number of values that can be passed to the function.

CodePudding user response：

Python does not copy the list before passing it to the function. Instead it passes a reference to the entire array, which takes the same amount of time whether the list is of length 3 or length 1000000. So you cannot reduce the computation time, and you should not try.

Computers are fast. Unless your program is too slow, don't worry about computation speed.