倍频程函数定义错误

Question

I am trying to use octave for the first time and I want to create a function as follows:

1;
 function test=calc(x)
         a=x^2;
         factorial(a)
 endfunction

 val = calc (3)

I saved this as calc.m and when I run it I get an error that variable x is not defined.

What am I doing wrong?

Update: The original question I managed to get working but now I ended up with another problem. Please consider the following code:

init = 5.;
function val=prodval(x)
  global init;
  val=x+init^2;
endfunction
fin=prodval(3)

When I save the script as test.m and run it i get the following error:

>> test

error: for x^A, A must be a square matrix.  Use .^ for elementwise power.
error: called from
    prodval at line 5 column 6
    test at line 7 column 4

What exactly is going on here? I do not see where I defined a matrix by mistake... I also realise that this may not be the best definition of a function but I am trying...

Answer 1

[UPDATE]

For each scope you want a global to be "visible" you have to declare it as global. Reference

global init = 5;
function val = prodval (x)
   global init;
   val = x + init^2;  
endfunction

fin=prodval(3)
fin =  28