hello, i want to solve a nonlinear matrix using newton Raphson method but i have some problems with my code. does anybody know what and where is the problem?

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jorge alejandro guerrero díaz 2017-12-10

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评论： Torsten 2017-12-11

function y=newtonsistema
 xo=[0;0;0];
 syms x y z
 mi = rand;
 fname=[1/pi*(cos(x)-cos(y)+cos(z))- mi;cos(5*x)-cos(5*y)+cos(5*z);cos(7*x)-cos(8*y)+cos(7*z)];
 fprima=(jacobian(fname));
 tolerancia=1.e-10;
maxiter = 20;
 iter = 1;
 f=inline(fname);
 jf=inline(fprima);
 error=norm(f(xo(1),xo(2),xo(3)),2);
 fprintf('error=%12.8f\n', error);
 while error >= tolerancia
    fxo=f(xo(1),xo(2),xo(3));
    fpxo=jf(xo(1),xo(2),xo(3));
    x1=xo-pinv(fpxo)*fxo;
    fx1=f(x1(1),x1(2),x1(3));
    error =norm((fx1),2);
    fprintf(' Iter %2d  raiz x=(%14.9f,%14.9f,%14.9f) f(x)=(%14.9f,%14.9f,%14.9f)\n',iter,x1(1),x1(2),x1(3),fx1(1),fx1(2),fx1(3));
    if iter > maxiter
        fprintf('Max number of iter' \n');
    return;
    end
    xo=x1;
    iter=iter+1;
      if true
        % code
      end
   end