function drawrosenbrock(allx)
% show path taken in minimizing Rosenbrock's function

% Rosenbrock-specifc part: plot contours and minimum
xx = [-1.5:.04:1.5];
yy = [-0.5:.04:1.5];
[x,y] = meshgrid(xx,yy);
meshd = 100.*(y-x.*x).^2 + (1-x).^2; 
hold off;
contour(xx,yy,meshd,3.^(1:6),':')
hold on;
plot(1,1,'*');

% path-plotting part
plot(allx(1,1),allx(2,1),'o');
plot(allx(1,:),allx(2,:),'.-');