gusucode.com > demos工具箱matlab源码程序 > demos/penny.m

    %% Viewing a Penny
% This example shows four techniques to visualize the surface data of a
% penny. The file PENNY.MAT contains measurements made at the National
% Institute of Standards and Technology of the depth of the mold used to
% mint a U. S. penny, sampled on a 128-by-128 grid.

% Copyright 1984-2014 The MathWorks, Inc.

%% Drawing a Contour Plot
% Draw a contour plot with 15 copper colored contour lines.

load penny.mat
contour(P,15)
colormap(copper)
axis ij square


%% Drawing a Pseudocolor Plot
% Draw a pseudocolor plot with brightness proportional to height.

pcolor(P)
axis ij square
shading flat


%% Drawing a Pseudocolor Plot With a Colormap
% Draw a pseudocolor plot with brightness proportional to the Laplacian of the
% height. A cell is bright if its height is greater than the average of its
% four neighbors and dark if its height is less than the average of its four
% neighbors. This is an unusual "lighting model", but it produces an image
% that looks like a photograph of a penny.

D = -del2(P);
pcolor(D)
axis ij square
shading flat


%% Drawing a Surface Plot With a Colormap
% Finally, produce a 3-D, copper colored, surface plot with the Laplacian
% lighting model.

surf(P,D);
axis ij tight
shading flat
view(-20,75)