function splt(n,U);
hold off
tt=(0:1:n)/n;
x=tt;
%  surf(tt,x,U), shading interp, lighting phong, axis tight
%  view([-90 90]), colormap(spring); 
%  %set(gca,'zlim',[-5 50])
%  light('color',[1 1 0],'position',[-1,2,2])
% $$$ material([0.30 0.60 0.60 40.00 1.00]);
%mesh(tt,x,U);
surf(tt,x,U);
axis([0,1,0,1,0,1])
drawnow
