I have an error on the following code.how to rectify the error ?

if true
clc;
clear all;
close all;
c = Ns;
d= 8;
z = f(c, d)
function z = f(c,d)
if ~mod(c,d)
  z=0
else
  z=d-mod(c,d);
end
end
end

Answer 1

[KSSV]

function z =  myfunction(Ns)
c = Ns;
d= 8;
z = f(c, d)
end
function z = f(c,d)
if ~mod(c,d)
  z=0
else
  z=d-mod(c,d);
end
end

Call the function:

Ns = rand ;  % any value
z = myfunction(Ns) ;

[PLACEIUS NISHIGA G]

Thank you sir.still I have a error likr this.

Error: File: file.m Line: 104 Column: 1

Function definitions are not permitted in this context.

how to clear this error?