www.pudn.com > 实验7-线形拟合.rar > gradrosen.m

function [f,g]=gradrosen(x) 
f=100*(x(2)-x(1)^2)^2+(1-x(1))^2;% compute the function value at x 
if nargout > 1   % fun called with 2 output arguments 
   g(1)=-2*(1-x(1))-400*x(1)*(x(2)-x(1)^2);   % compute the gradient evaluated at x 
   g(2)=200*(x(2)-x(1)^2);     
end