Método de la Secante- en Scilab

function y=f(x)
y=exp(-x^2)-x;
endfunction

function x = secante(x0,x1,tol)
j=2;
i=1;
x(1)=x0;
x(2)=x1;
ea(i)=100;
while abs(ea(i))>=tol
   x(j+1)=(x(j-1)*f(x(j))-x(j)*f(x(j-1)))/(f(x(j))-f(x(j-1)));
   ea(i+1)=abs((x(j+1)-x(j))/x(j+1))*100;
   j=j+1;
   i=i+1;     
end

printf(' i \t\t x(i) \t Error aprox (i) \n');
printf('%2d \t %11.7f \t \n',0,x(1));

for k=2:j;
    printf('%2d \t %11.7f \t %7.3f \n',k-1,x(k),ea(k-1));
end

endfunction