MATLAB Newton-Raphson ve yanlış pozisyon metoduyla ilgili yardım

x(1)=input('Enter Initial Guess:');
error=input('Enter allowed Error:');
f=inline(a)
dif=diff(sym(a));
d=inline(dif);
for i=1:100
x(i+1)=x(i)-((f(x(i))/d(x(i))));
err(i)=abs((x(i+1)-x(i))/x(i));
if err(i)<error
break
end
end
root=x(i)

clc 
 a=input('Please enter a function: ' , 's'); 
 epsilon = input('Please enter a tolerance: '); 
  
 f=inline('a','x'); 
  
  
 i=0; x0=0; h=0.5; 
  
 while abs(f(x0))> epsilon 
     x0=x0-(f(x0)*h/f(x0+h)-f(x0)); 
     fprintf('x=%.7f\n',x0); 
     i=i+1; 
 end 
  
 fprintf('root=%.7f',x0);