"Not enough input arguments" Help Don't understand why?

When I try and use the fzero function but keep getting this error:

Error using fzero (line 289) FZERO cannot continue because user supplied

function_handle ==> SCC failed with the error below.

 Not enough input arguments.

 Error in a6q7 (line 10)

 q=fzero('SCC',1);

The script is as follows:

 clear all

 clc

 z=sqrt(2)*sin(pi/4);

 A =z*z;

 B =z^0.5;

 C =3+2*z;

 x=0:10;

 y=SCC(x,A,B,C);

 plot(x,y)

 q=fzero('SCC',1);

And the function SCC is:

 function  y = SCC(x,A,B,C)

 y=A.*sin(x).*cos(x)+B.*cos(C.*x);

 end

Thanks for any help!

Answer 1

[Geoff Hayes]

Liam - according to the documentation for fzero, the input function handle is to a function that a accepts a scalar x and returns a scalar fun(x). Note that your function accepts four inputs, and so the error message, Not enough input arguments, makes sense since there fsolve will only try to provide one.

If x is your only variable into SCC, and the remaining three parameters, A, B, and C, are constant, then I would replace your line of code

 q=fzero('SCC',1);

with an anonymous function that makes use of SCC as

 q=fzero(@(x)SCC(x,A,B,C),1);

In the above, we are now supplying a function to fzero that will accept a single input argument only, and use the A, B, and C that have been defined previously. See anonymous functions for more details.

Try the above and see what happens!

[L_B]

Thanks for the explanation really helped! I used the global function to get it to work after but thanks very much!