% Steffensens Method

clear;
% Generating a sequence from a functional iteration

itmax=input('itmax=');
p1=input('p1='); 
p2=feval('gnn',p1); 
p3=feval('gnn',p2);

% Generating a Steffensen seq. from ps

for l=1:itmax
   pa(l)=p1-(p2-p1)^2/(p3-2*p2+p1); 
   p1=pa(l);
   p2=feval('gnn',p1); 
	 p3=feval('gnn',p2);
end
disp(pa');