%% Newton method matlab code animation
%Dejen Ketema,  March,2019. 
function p=newton_plot_2019(f,df,p0,xmin,xmax,tol)
xx=linspace(xmin,xmax,1000);
plot(xx,f(xx),'linewidth',2)
line([xmin,xmax],[0,0],'linewidth',2,'color','b');
grid on

fprintf(' n         p          |p-p0|   \n');
fprintf('-------------------------------\n');
for n=1:100
  p=p0-f(p0)/df(p0);
  fprintf('%2d  %12.8f  %12.8f\n',n,p,abs(p-p0));
  line([p0,p0],[0,f(p0)],'color','r','linewidth',2);
  line(p0,f(p0),'marker','.','color','r'); pause(1);
  line([p0,p],[f(p0),0],'color','r','linewidth',2); pause(1);
   if abs(p-p0)<tol
      break;
  end
  p0=p;
end