How can i make a changeable function input in a matlab function.

I got this function made to calculate the radical of a standard function f(x)=x^4-x-3 and works fine.. But i want to know if its possible to make my f(x) changeable some way, so i can use this function to calculate any f(x) type.

 function xi = midpointf(a,b,N)
ai(1)=a; bi(1)=b;
for i=2:N+1;
xi=(ai(i-1)+bi(i-1))/2;
fx=xi^4-xi-3;
fa=ai(i-1)^4-ai(i-1)-3;
if fx==0
    'radical'
    xi
elseif fx*fa >0
    ai(i)=xi; bi(i)=bi(i-1);
else
    ai(i)=ai(i-1); bi(i)=xi;
end
end
'radical'
xi

Answer 1

[Sean de Wolski]

Sure. You'll need to use function handles.

http://www.mathworks.com/help/releases/R2013b/matlab/ref/function_handle.html

[pan]

you mean i should create a handle before running the function and use the handle as an input, right?

[Sean de Wolski]

Yup!

Pass in the function handle and then your solver above will do the same set of instructions on it regardless of what it's actually calculating.

[pan]

It worked fine, ty! :) I knew about handle but didn't know how to use it properly :P Had to read more careful.. thanks again