n = 21;
map=copper(n);
colormap(map)
subplot(2,1,1)
x=0:n;
y=[0 1];
[xx,yy]=meshgrid(x,y);
c=[1:n+1;1:n+1];
pcolor(xx,yy,c)
set(gca,'Yticklabel','')
title('Figure 27.1a: Pcolor of Copper')
subplot(2,1,2)
rgbplot(map)
xlim([0,n])
title('Figure 27.1b: RGBplot of Copper')