matlab代码

三维螺旋线图
t=0:pi/10:10*pi;
x=2.*cos(t);y=2.*sin(t);z=2.*t;
plot3(x,y,z);xlabel('x轴'),ylabel('y轴'),zlabel('z轴')

球面的网线图
[x,y,z]=sphere(30);
xx=2.*x;yy=2.*y;zz=2.*z;
mesh(xx,yy,zz),xlabel('x轴'),ylabel('y轴'),zlabel('z轴')


旋转抛物面
x=-2:0.01:2;y=-2:0.01:2;
[xx,yy]=meshgrid(x,y);zz=xx.^2+yy.^2;
ii=find(xx.^2+yy.^2>4);zz(ii)=NaN;
surf(xx,yy,zz)

墨西哥曲线
x=-10:0.5:10;y=-8:0.5:8;
[x,y]=meshgrid(x,y);
z=sin(sqrt(x.^2+y.^2))./sqrt(x.^2+y.^2);
mesh(x,y,z);


马鞍面与平面的交
[x,y]=meshgrid(-10:0.2:10,-10:0.2:10);
z1=(x.^2-2*y.^2)+eps;z2=-20*ones(size(x));
mesh(x,y,z1);
hold on;
mesh(x,y,z2);
hold off;

纸折的
const=0;
x=1:0.1:10;y=1:0.1:10;z=0:0.1:10;
[x,y,z]=meshgrid(x,y,z);
f=(x+y+z).*(x.*y+x.*z+y.*z)-10*x.*y.*z-const;
p=patch(isosurface(x,y,z,f,0));
set(p, 'FaceColor', 'red', 'EdgeColor', 'none');
daspect([1 1 1])
view(3)
camlight; lighting phong

心形图
[x,y,z]=meshgrid(linspace(-1.3,1.3));
val=(x.^2 + (9/4)*y.^2 + z.^2 - 1).^3 - x.^2.*z.^3 - (1/9)*y.^2.*z.^3;
isosurface(x,y,z,val,0)
axis equal
view(-10,24)

世界地图
h=worldmap('World'); setm(h,'Origin',[0 180 0]) land=shaperead('landareas','UseGeoCoords',true); geoshow(h,land,'FaceColor',[0.5 0.7 0.5]) lakes=shaperead('worldlakes','UseGeoCoords',true); geoshow(lakes,'FaceColor','blue') rivers=shaperead('worldrivers','UseGeoCoords',true); geoshow(rivers,'Color','blue') cities=shaperead('worldcities','UseGeoCoords',true); geoshow(cities,'Marker','.','Color','red')


中国地图
% 把台湾和大陆合成一个文件保存起来，这样画图用patch就是一种颜色（Zhou Feng, 2008-06-30, SOED, Hangzhou）。
%
% by ZHOU Feng
% zhoufeng@sio.org.cn
% SOED, 2nd Institute of Oceanography
% 2008-06-30

s1 = worldhi('china');
s2 = worldhi('taiwan');
disp(s1);

% add Taiwan together (ZHOU Feng)zhoufeng@sio.org.cn
s = s1;
s.lat = [s1.lat;NaN; s2.lat];
s.long= [s1.long; NaN;s2.long];

% add the Diaoyu Island (钓鱼岛)
% 钓鱼岛群岛由钓鱼岛、黄尾岛、赤尾岛、南小岛、北小岛、大南小岛、大北小岛和飞濑岛等岛屿组成，总面积约7平方公里。
% 地理位置：东经123°-124°34′北纬25°40′-26°。
%
% ---这里的分辨率只有两块 --
s3 = worldhi('japan'); %(ZHOU Feng)zhoufeng@sio.org.cn
x = s3.long;
y = s3.lat;
idx = find(x>123.0 & x<124.5);
idy = find(y> 25.5 & y< 26.0);
m = length(idy);
id=[];
for i=1:m
tmp=find(idx == idy(i));
if isempty(tmp)
else
id = [id; idx(tmp)]; %(ZHOU Feng)zhoufeng@sio.org.cn
end
end
%%longd = x(id);
%%latd = y(id);
%
% find nan
dtmp = find(diff(id)>1);
if isempty(dtmp)
disp('no change')
elseif length(dtmp)==1
idnew = [id(1:dtmp); id(dtmp+1)-1;id(dtmp+1:end)];
else
for j=1:length(dtmp)
idnew = [id(1:dtmp(j)+j-1); id(dtmp(j)+1)+j-1; id(dtmp(j)+j+1:end)]; % 未