% 實例23：視角的調整

function shili23
h0=figure('toolbar','none',...
    'position',[200 150 450 350],...
    'name','實例23');
x=-5:0.5:5;
[x,y]=meshgrid(x);
r=sqrt(x.^2+y.^2)+eps;
z=sin(r)./r;
subplot(2,2,1)
surf(x,y,z)
xlabel('X-axis')
ylabel('Y-axis')
zlabel('Z-axis')
title('Figure1')
view(-37.5,30)

subplot(2,2,2)
surf(x,y,z)
xlabel('X-axis')
ylabel('Y-axis')
zlabel('Z-axis')
title('Figure2')
view(-37.5+90,30)

subplot(2,2,3)
surf(x,y,z)
xlabel('X-axis')
ylabel('Y-axis')
zlabel('Z-axis')
title('Figure3')
view(-37.5,60)

subplot(2,2,4)
surf(x,y,z)
xlabel('X-axis')
ylabel('Y-axis')
zlabel('Z-axis')
title('Figure4')
view(180,0)

% 實例24：向量場的繪制

function shili24
h0=figure('toolbar','none',...
    'position',[200 150 450 350],...
    'name','實例24');
subplot(2,2,1)
z=peaks;
ribbon(z)
title('Figure1')

subplot(2,2,2)
[x,y,z]=peaks(15);
[dx,dy]=gradient(z,0.5,0.5);
contour(x,y,z,10)
hold on
quiver(x,y,dx,dy)
hold off
title('Figure2')

subplot(2,2,3)
[x,y,z]=peaks(15);
[nx,ny,nz]=surfnorm(x,y,z);
surf(x,y,z)
hold on
quiver3(x,y,z,nx,ny,nz)
hold off
title('Figure3')

subplot(2,2,4)
x=rand(3,5);
y=rand(3,5);
z=rand(3,5);
c=rand(3,5);
fill3(x,y,z,c)
grid on
title('Figure4')

% 實例25：燈光定位

function shili25
h0=figure('toolbar','none',...
    'position',[200 150 450 250],...
    'name','實例25');
vert=[1 1 1;1 2 1;
    2 2 1;2 1 1;
    1 1 2;1 2 2;
    2 2 2;2 1 2];
fac=[1 2 3 4;2 6 7 3;
    4 3 7 8;1 5 8 4;
    1 2 6 5;5 6 7 8];
grid off
sphere(36)
h=findobj('type','surface');
set(h,'facelighting','phong',...
    'facecolor',...
    'interp',...
    'edgecolor',[0.4 0.4 0.4],...
    'backfacelighting',...
    'lit')
hold on
patch('faces',fac,'vertices',vert,...
    'facecolor','y');
light('position',[1 3 2]);
light('position',[-3 -1 3]);
material shiny
axis vis3d off
hold off

% 實例26：柱狀圖

function shili26
h0=figure('toolbar','none',...
    'position',[200 50 450 450],...
    'name','實例26');
subplot(2,1,1)
x=[5 2 1
    8 7 3
    9 8 6
    5 5 5
    4 3 2];
bar(x)
xlabel('X軸');
ylabel('Y軸');
title('第一子圖');

subplot(2,1,2)
y=[5 2 1
    8 7 3
    9 8 6
    5 5 5
    4 3 2];
barh(y)
xlabel('X軸');
ylabel('Y軸');
title('第二子圖');

% 實例27：設置照明方式

function shili27
h0=figure('toolbar','none',...
    'position',[200 150 450 350],...
    'name','實例27');
subplot(2,2,1)
sphere
shading flat
camlight left
camlight right
lighting flat
colorbar
axis off
title('Figure1')

subplot(2,2,2)
sphere
shading flat
camlight left
camlight right
lighting gouraud
colorbar
axis off
title('Figure2')

subplot(2,2,3)
sphere
shading interp
camlight right
camlight left
lighting phong
colorbar
axis off
title('Figure3')

subplot(2,2,4)
sphere
shading flat
camlight left
camlight right
lighting none
colorbar
axis off
title('Figure4')

% 實例28：羽狀圖

function shili28
h0=figure('toolbar','none',...
    'position',[200 150 450 350],...
    'name','實例28');
subplot(2,1,1)
alpha=90:-10:0;
r=ones(size(alpha));
m=alpha*pi/180;
n=r*10;
[u,v]=pol2cart(m,n);
feather(u,v)
title('羽狀圖')
axis([0 20 0 10])

subplot(2,1,2)
t=0:0.5:10;
x=0.05+i;
y=exp(-x*t);
feather(y)
title('復數矩陣的羽狀圖')

% 實例29：立體透視（1）

function shili29
h0=figure('toolbar','none',...
    'position',[200 150 450 250],...
    'name','實例29');
[x,y,z]=meshgrid(-2:0.1:2,...
    -2:0.1:2,...
    -2:0.1:2);
v=x.*exp(-x.^2-y.^2-z.^2);
grid on
for i=-2:0.5:2;
    h1=surf(linspace(-2,2,20),...
        linspace(-2,2,20),...
        zeros(20)+i);
    rotate(h1,[1 -1 1],30)
    dx=get(h1,'xdata');
    dy=get(h1,'ydata');
    dz=get(h1,'zdata');
    delete(h1)
    slice(x,y,z,v,[-2 2],2,-2)
    hold on
    slice(x,y,z,v,dx,dy,dz)
    hold off
    axis tight
    view(-5,10)
    drawnow
end

% 實例30：立體透視（2）

function shili30
h0=figure('toolbar','none',...
    'position',[200 150 450 250],...
    'name','實例30');
[x,y,z]=meshgrid(-2:0.1:2,...
    -2:0.1:2,...
    -2:0.1:2);
v=x.*exp(-x.^2-y.^2-z.^2);
[dx,dy,dz]=cylinder;
slice(x,y,z,v,[-2 2],2,-2)
for i=-2:0.2:2
    h=surface(dx+i,dy,dz);
    rotate(h,[1 0 0],90)
    xp=get(h,'xdata');
    yp=get(h,'ydata');
    zp=get(h,'zdata');
    delete(h)
    hold on
    hs=slice(x,y,z,v,xp,yp,zp);
    axis tight
    xlim([-3 3])
    view(-10,35)
    drawnow
    delete(hs)
    hold off
end

% 實例31：表面圖形

function shili31
h0=figure('toolbar','none',...
    'position',[200 150 550 250],...
    'name','實例31');
subplot(1,2,1)
x=rand(100,1)*16-8;
y=rand(100,1)*16-8;
r=sqrt(x.^2+y.^2)+eps;
z=sin(r)./r;
xlin=linspace(min(x),max(x),33);
ylin=linspace(min(y),max(y),33);
[X,Y]=meshgrid(xlin,ylin);
Z=griddata(x,y,z,X,Y,'cubic');
mesh(X,Y,Z)
axis tight
hold on
plot3(x,y,z,'.','Markersize',20)

subplot(1,2,2)
k=5;
n=2^k-1;
theta=pi*(-n:2:n)/n;
phi=(pi/2)*(-n:2:n)'/n;
X=cos(phi)*cos(theta);
Y=cos(phi)*sin(theta);
Z=sin(phi)*ones(size(theta));
colormap([0 0 0;1 1 1])
C=hadamard(2^k);
surf(X,Y,Z,C)
axis square

% 實例32：沿曲線移動的小球

h0=figure('toolbar','none',...
    'position',[198 56 408 468],...
    'name','實例32');
h1=axes('parent',h0,...
    'position',[0.15 0.45 0.7 0.5],...
    'visible','on');
t=0:pi/24:4*pi;
y=sin(t);
plot(t,y,'b')
n=length(t);
h=line('color',[0 0.5 0.5],...
    'linestyle','.',...
    'markersize',25,...
    'erasemode','xor');
k1=uicontrol('parent',h0,...
    'style','pushbutton',...
    'position',[80 100 50 30],...
    'string','開始',...
    'callback',[...
        'i=1;',...
        'k=1;,',...
        'm=0;,',...
        'while 1,',...
        'if k==0,',...
        'break,',...
        'end,',...
        'if k~=0,',...
        'set(h,''xdata'',t(i),''ydata'',y(i)),',...
        'drawnow;,',...
        'i=i+1;,',...
        'if i>n,',...
        'm=m+1;,',...
        'i=1;,',...
        'end,',...
        'end,',...
        'end']);
k2=uicontrol('parent',h0,...
    'style','pushbutton',...
    'position',[180 100 50 30],...
    'string','停止',...
    'callback',[...
        'k=0;,',...
        'set(e1,''string'',m),',...
        'p=get(h,''xdata'');,',...
        'q=get(h,''ydata'');,',...        
        'set(e2,''string'',p);,',...
        'set(e3,''string'',q)']);
k3=uicontrol('parent',h0,...
    'style','pushbutton',...
    'position',[280 100 50 30],...
    'string','關閉',...
    'callback','close');
e1=uicontrol('parent',h0,...
    'style','edit',...
    'position',[60 30 60 20]);
t1=uicontrol('parent',h0,...
    'style','text',...
    'string','循環次數',...
    'position',[60 50 60 20]);
e2=uicontrol('parent',h0,...
    'style','edit',...
    'position',[180 30 50 20]);
t2=uicontrol('parent',h0,...
    'style','text',...
    'string','終點的X坐標值',...
    'position',[155 50 100 20]);
e3=uicontrol('parent',h0,...
    'style','edit',...
    'position',[300 30 50 20]);
t3=uicontrol('parent',h0,...
    'style','text',...
    'string','終點的Y坐標值',...
    'position',[275 50 100 20]);