what is wrong in this code not executing .??????Error: File: ifSf.m Line: 2 Column: 22 Invalid expression. Check for missing multiplication operator, missing or unbalanced del

%Intuitionistic Fuzzy S-shaped Function (ifSf)
function[y,z]=ifSf(x,245131.735,16960.70,0)
y=zeros(1,length(x));
z=zeros(1,length(x));
for j=1:length(x)
    if(x(j)<=16960.70) 
        y(j)=0;
        z(j)=1;
    elseif(x(j)>16960.70)&&(x(j)<=((16960.70+245131.735)/2))
        y(j)=2*(((x(j)-16960.70)/(245131.735-16960.70))^2);
        z(j)=1-(2*(((x(j)-16960.70)/(245131.735-16960.70))^2));
    elseif(x(j)>=((16960.70+245131.735)/2))&&(x(j)<245131.735)
        y(j)=1-(2*(((x(j)-16960.70)/(245131.735-16960.70))^2));
        z(j)=2*(((x(j)-16960.70)/(245131.735-16960.70))^2);
    elseif(x(j)>=245131.735)
        y(j)=1;
        z(j)=0;
    end
    plot(x,y,x,z)
    legend('Membership function','Non-membership function')
end

[Stephen23]

The input arguments to a function must be variable names. It is not possible to specify numeric values like this:

function[y,z]=ifSf(x,245131.735,16960.70,0)
%                    ^^^^^^^^^^ ^^^^^^^^ ^ invalid syntax

https://www.mathworks.com/help/matlab/ref/function.html

Answer 1

[Chunru]

%function[y,z]=ifSf(x,245131.735,16960.70,0)
function[y,z]=ifSf(x)  % for function definition, arguments must be variables (not constants)

Answer 2

[Steven Lord]

To clarify what @Stephen23 and @Chunru said, when you define a function all the input arguments that you specify must be either variable names or varargin. When you call a function you must specify values to be assigned to those variable names inside your function.

As an example, I'm going to call the function myfun1783240 with inputs 1:5 and 3, but inside myfun1783240 those inputs will be referred to as x and banana.

myfun1783240(1:5, 3)

ans = 1×5

1 8 27 64 125

If you'd wanted a version of myfun1783240 that "fixed" the value of banana as 2, you could do so using an anonymous function.

banana2 = @(x) myfun1783240(x, 2);
banana2(1:5) % [1 4 9 16 25]

ans = 1×5

1 4 9 16 25

function out = myfun1783240(x, banana)
out = x.^banana;
end