MATLAB: Problem with the Code

code problemnewton's method

[EDIT: 20110512 17:03 EDT – reformat – WDR]
I keep getting the error Undefined function or method 'Newton' for input arguments of type 'inline'. I'm doing newtons method and I can't figure out what that error means and what part of my code is wrong.
function x = Newton(f, fp, x, nmax, error)
x=1;
e=2.71828;
f(x)=inline('(x)*(5000)*(e^(-x)))-((100)+(0.73)*(5000)*(e^(-x))');
fp(x)=inline('-5000*(e^(-x))*(x-1.73)');
nmax = 10;
error = 1.0e-15;
x = Newton(f,fp,x,nmax,error)
fprintf('x(0) = %10g \n', x)
for n = 1:nmax
      d = f(x)/fp(x);
      x = x - d;
      fprintf('x(%i) = %10g \n', n, x)
      if abs(d) < error
          fprintf('Converged! \n')
          return
      end
  end
  end

Best Answer

There's no Newton function on MATLAB current path or any other path that MATLAB is aware, you get the same error for
whateverfunctionisayso(inline('x'))
This should be your script:
x=1; 
f=inline('x*5000*exp(-x)-(100+0.73*5000*exp(-x))'); 
fp=inline('-5000*exp(-x)*(x-1.73)'); 
nmax = 10; 
error = 1.0e-15; 
x = Newton(f,fp,x,nmax,error) 
fprintf('x(0) = %10g \n', x)
And this is your function:
function x = Newton(f, fp, x, nmax, error)
for n = 1:nmax 
 d = f(x)/fp(x); 
 x = x - d; 
 fprintf('x(%i) = %10g \n', n, x) 
 if abs(d) < error 
 fprintf('Converged! \n') 
 return 
 end 
end 
end
Save the function to the current path or another that MATLAB is aware of and run the script.
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