In a file named addme.m, create a function that accepts up to two inputs. Use nargin in the body of the function to determine the number of inputs.

type addme.m

function c = addme(a,b)
    switch nargin
        case 2
            c = a + b;
        case 1
            c = a + a;
        otherwise
            c = 0;
    end
end

At the command prompt, call the addme function with two inputs.

c = addme(13,42)

c = 55

Call the function with one input.

c = addme(13)

c = 26

Determine how many inputs a function accepts.

The function addme created in the previous example, has two inputs in its declaration statement (a and b). Define the name of the function as a character vector and use it as input for nargin.

fun = 'addme';
nargin(fun)

ans = 2

Determine how many inputs a function that uses varargin can accept.

In a file named mynewplot.m, create a function that accepts numeric inputs x and y and any number of additional plot inputs using varargin.

type mynewplot.m

function mynewplot(x,y,varargin)
    figure
    plot(x,y,varargin{:})
    title('My New Plot')
end

Query how many inputs newplot can accept.

fx = 'mynewplot';
nargin(fx)

ans = -3

The minus sign indicates that the third input is varargin. The mynewplot function can accept an indeterminate number of additional input arguments.