在matlab 画箭头

[转载]在matlab 画箭头

原文地址： 在matlab 画箭头 作者： 纯情小郎君

完整见链接http://www.mathworks.com/matlabcentral/fx_files/14056/1/content/arrow3_examples.html

ARROW3   EXAMPLES   (R13)

• Two-dimensional Quiver Plots
  • Example 1.
  • Example 2.
  • Example 3.
• Three-Dimensional Quiver Plots
  • Example 4.
  • Example 5.
• Cone Plots
  • Example 6.
  • Example 7.
• Feather Plots
  • Example 8.
  • Example 9.
• Compass Plots
  • Example 10.
  • Example 11.
• Reference Frames
  • Example 12.
  • Example 13.
  • Example 14.
• Named Colors
  • Example 15.
• Update (Modify and Restore)
  
  • Example 16.

Two-Dimensional Quiver Plots

Example 1. (cf.  Joukowski Airfoil Transformation)

t=10*pi/180; u=0.1; v=0.1; r=1.1; tol=8e-2;
s=u+i*v; k=2*r*sin(t); w=exp(i*t);
[x,y]=meshgrid(-2.5:0.1:3.5,-3:0.1:3);
z=x+i*y; z(abs(z-s)f=w*z+exp(-i*t)*r^2./(z-s)+i*k*log(z);
a=0:0.1:2*pi; zc=r*(cos(a)+i*sin(a))+s;
c1=-1.5; c2=2.5; c3=c2-c1;
c=contour(x,y,imag(f),c1:c3/16:c2);
set(gca,'color',0.5*[1 1 1])
hold on, daspect([1 1 1])
fill(real(zc),imag(zc),'y'), colorbar
map=get(gcf,'colormap');
domain=0:1/(size(map,1)-1):1; m=1;
while mif c(2,m)>9, p=c(:,m+1:n)';
    if p(end,1)>p(1,1), p=flipud(p); end
    ndx=10:10:length(p);
    p2=p(ndx,:); p1=p(ndx-3,:);
    cc=interp1(domain,map,(c(1,m)-c1)/c3);
    set(gca,'ColorOrder',cc)
    arrow3(p1,p2,'0o',0.8)
end, m=n+1;
end, hold off


Example 1. Joukowski Airfoil Transformation

Example 2. (cf.  Quiver)

[x,y]=meshgrid(-1:1/21:1);
z=x.*exp(-x.^2-y.^2);
[c,h]=contour(x,y,z);
set(h,'EdgeColor',0.45*[1 1 1])
ndx=1:3:length(x);
x=x(ndx,ndx); y=y(ndx,ndx); z=z(ndx,ndx);
[u,v]=gradient(z,1/7);
p1=[x(:),y(:)]; u=u(:); v=v(:);
m=abs(u+i*v); % gradient magnitude
daspect([1 1 1]), set(gca,'color',0.3*[1 1 1])
hold on, colormap hot, scale=0.4;
arrow3(p1,p1+scale*[u,v],'|',min(1.25*m,0.85))
hold off, h=colorbar;
set(h,'YTickLabel',num2str(str2num(get(h,...
'YTickLabel'))/scale))


Example 2. Surface Gradients

Example 3. (cf.  Two-Dimensional Quiver Plots)

[x,y,z]=peaks(-2:0.05:2);
contour(x,y,z,10); h=gca;
ndx=1:4:length(x);
x=x(ndx,ndx); y=y(ndx,ndx); z=z(ndx,ndx);
[u,v]=gradient(z,0.2);
p1=[x(:),y(:)]; u=u(:); v=v(:);
m=abs(u+i*v); % gradient magnitude
hold on, daspect([1 1 1]), scale=0.025;
arrow3(p1,p1+scale*[u,v],'|',0.9*m/max(m))
hold off, title('Dual Colormap')
h1=colorbar; h2=copyobj(h1,gcf);
set(h,'color',0.4*[1 1 1],...
'position',get(h,'position')+[0.05 0 0 0])
% ----------------------------------------------------- Right Colorbar
p=get(h1,'position');
set(h1,'position',[0.87,p(2),0.05,p(4)],...
'YTickLabel',num2str(str2num(get(h1,...
'YTickLabel'))/scale))                               % freeze labels
map=colormap; cdata=reshape(map,size(map,1),1,3);
set(get(h1,'children'),'cdata',cdata)              % freeze colors
set(get(h1,'title'),'string','Gradient')
% ------------------------------------------------------ Left Colorbar
caxis auto, colorbar, colormap autumn
set(h2,'YAxisLocation','left',...
'position',[0.08,p(2),0.05,p(4)])
set(get(h2,'title'),'string','Contour')


Example 3. Dual Colormap

Three-Dimensional Quiver Plots

Example 4. (cf.  Quiver3)

[x,y]=meshgrid(-2:0.25:2,-1:0.25:1);
z=x.*exp(-x.^2-y.^2);
surf(x,y,z,'EdgeColor','none')
axis([-2.5 2.5 -1.5 1.5 -1 1]), daspect([1 1 1])
set(gca,'CameraViewAngle',7)
[u,v,w]=surfnorm(x,y,z);
p1=[x(:),y(:),z(:)]; N=[u(:),v(:),w(:)];
hold on
arrow3(p1,p1+0.5*N,'1.5_b')
hold off, colormap spring
light('position',[-1 -1 -1],'style','local')
light('position',[0 1 1]), lighting gouraud


Example 4. Surface Normals

Example 5. (cf.  Three-Dimensional Quiver Plots)

vx=2; vy=3; vz=10; a=-32; t=(0:.1:1)';
x=vx*t; y=vy*t; z=vz*t+1/2*a*t.^2;
r=[x,y,z]; v=gradient(r')';
axis([0 3 0 4 -10 2]), pbaspect([2 1 1])
hold on, grid on, view([70 18])
arrow3(r,r+v,'b',0.9)
hold off


Example 5. Velocity Vectors

Cone Plots

Example 6. (cf.  Coneplot)

load wind, wind_speed=sqrt(u.^2+v.^2+w.^2);
xmin=min(x(:)); xmax=max(x(:));
ymin=min(y(:)); ymax=max(y(:));
zmin=min(z(:));
hsurfaces=slice(x,y,z,wind_speed,[xmin,xmax],ymax,zmin);
set(hsurfaces,'FaceColor','interp','EdgeColor','none',...
              'AmbientStrength',0.6)
hold on, daspect([2,2,1]), view(30,40), axis tight
xrange=linspace(xmin,xmax,8);
yrange=linspace(ymin,ymax,8);
[cx cy cz]=meshgrid(xrange,yrange,3:4:15);
ui=interp3(x,y,z,u,cx,cy,cz);
vi=interp3(x,y,z,v,cx,cy,cz);
wi=interp3(x,y,z,w,cx,cy,cz);
m=sqrt(ui.^2+vi.^2+wi.^2); m=m(:)/30;
p1=[cx(:),cy(:),cz(:)]; p2=[ui(:),vi(:),wi(:)];
hcones=arrow3(p1,p2,'r',m,3*m,'cone');
set(hcones,'DiffuseStrength',0.8)
hold off, axis off
camproj perspective, camzoom(1.2)
camlight right, lighting phong


Example 6. Wind Speed and Direction

Example 7. (cf.  Vector Field Displayed with Cone Plots)

load wind, wind_speed=sqrt(u.^2+v.^2+w.^2);
hiso=patch(isosurface(x,y,z,wind_speed,40),...
          'FaceColor','red','EdgeColor','none');
isonormals(x,y,z,wind_speed,hiso)
hcap=patch(isocaps(x,y,z,wind_speed,40),...
          'FaceColor','interp','EdgeColor','none',...
          'AmbientStrength',0.6);
hold on, colormap hsv, daspect([1,1,1]), view(65,45)
[f verts]=reducepatch(isosurface(x,y,z,wind_speed,30),0.07);
cx=verts(:,1); cy=verts(:,2); cz=verts(:,3);
ui=interp3(x,y,z,u,cx,cy,cz);
vi=interp3(x,y,z,v,cx,cy,cz);
wi=interp3(x,y,z,w,cx,cy,cz);
m=sqrt(ui.^2+vi.^2+wi.^2); m=m(:)/40;
p1=[cx(:),cy(:),cz(:)]; p2=[ui(:),vi(:),wi(:)];
h1=arrow3(p1,p2,'b',m,3*m,'cone');
xrange=linspace(min(x(:)),max(x(:)),10);
yrange=linspace(min(y(:)),max(y(:)),10);
[cx,cy,cz]=meshgrid(xrange,yrange,3:4:15);
ui=interp3(x,y,z,u,cx,cy,cz);
vi=interp3(x,y,z,v,cx,cy,cz);
wi=interp3(x,y,z,w,cx,cy,cz);
m=sqrt(ui.^2 + vi.^2 + wi.^2); m=m(:)/50;
p1=[cx(:),cy(:),cz(:)]; p2=[ui(:),vi(:),wi(:)];
h2=arrow3(p1,p2,'g',m,3*m,'cone');
hold off, axis tight, box on
set(gca,'xtick',[],'ytick',[],'ztick',[])
camproj perspective, camzoom(1.2)
camlight(-45,45), lighting phong


Example 7. Wind Speed and Direction

Feather Plots

Example 8. (cf.  Feather)

theta=(-90:10:90)'*pi/180;
n=length(theta); p1=[1:n;zeros(1,n)]';
r=2*ones(n,1); [u,v]=pol2cart(theta,r);
plot([1 n],[0 0],'r')
axis([0 20 -2 2]), daspect([8 2 1])
hold on, grid on
arrow3(p1,p1+[u,v],'r',0.9)
hold off


Example 8. Feather Plot

Example 9. (cf.  Plotting Complex Numbers)

t=(0:0.5:10)'; s=0.05+i; Z=exp(-s*t);
n=length(Z); p1=[1:n;zeros(1,n)]';
plot([1 n],[0 0],'b')
axis([0 22 -1 1]), daspect([8 1 1])
hold on, grid on
arrow3(p1,p1+[real(Z),imag(Z)],'b',0.8)
hold off


Example 9. Complex Number Plot

Compass Plots

Example 10. (cf.  Compass Plots)

wdir =[45 90 90 45 360 335 360 270 335 270 335 335];
knots=[ 6 6 8 6   5   9   8   8   9 10 14 12];
[x,y]=pol2cart(wdir*pi/180,knots);
polar(0,15), axis(15.9*[-1 1 -1 1])
hold on
arrow3(zeros(length(x),2),[x',y'],'r',1.25)
hold off


Example 10. Wind Speed and Direction

Example 11. (cf.  Compass)

Z=eig(randn(20)); m=abs(Z);
R=ceil(max(m)); r=R+0.3;
polar(0,R), axis(r*[-1 1 -1 1])
hold on
arrow3(zeros(length(Z),2),[real(Z),imag(Z)],'b',1.75*m/R)
hold off


Example 11. Complex Number Plot

Reference Frames

Example 12. Coordinate Axes

p=[4 2 1]; axis([-6 6 0 5 -1 1])
pbaspect([2 1.5 1]), view(55,15)
hold on
arrow3(repmat([p(1:2),0],4,1),...
[0 p(2) 0;p(1) 0 0;p;0 0 0],'--o',0,0,0.5)
arrow3(zeros(3),diag([7,5,1]),'o')
arrow3([0 0 0],p,'2.5s',1.5,[],0)
hold off, axis off, camlight left
set(gca,'CameraViewAngle',4)
text(7.1,0,0,'X'), text(0,5.05,0,'Y')
text(0,0,1,'Z','VerticalAlignment','bottom',...
'HorizontalAlignment','center')


Example 12. Coordinate Axes

Example 13. Eigenvectors

n=500; % generate test data
newz=[ 1 1 1]/sqrt(3);
newy=[ 0 -1 1]/sqrt(2);
newx=cross(newy,newz);
R=[newx;newy;newz]; % rotation matrix
U=randn(n,3)*diag([1,2,3])*R;
u=U(:,1)+10; v=U(:,2)+20; w=U(:,3)+30;
% plot eigenvectors with mean origin
plot3(u,v,w,'r.')
axis([0 20 10 29 20 40]), daspect([1 1 1])
view([-70,15]), set(gca,'CameraViewAngle',8)
hold on, grid on
mu=repmat(mean([u,v,w]),3,1);
[V,D]=eig(cov([u,v,w]));
p=9*V'+mu;
arrow3(mu,p,[],1.25,[],0)
p=p+ones(3);
text(p(1,1),p(1,2),p(1,3),'bfU')
text(p(2,1),p(2,2),p(2,3),'bfV')
text(p(3,1),p(3,2),p(3,3),'bfW')
hold off


Example 13. Eigenvectors

Example 14. (cf.  Frenet)

z=(0:2/99:2)'; t=2*pi*z; r=2+z;
x=r.*cos(t); y=r.*sin(t);
R=[x,y,z]; dR=gradient(R')';
m=repmat(sqrt(sum(dR.*dR,2)),1,3);
T=dR./m; dT=gradient(T')';
m=repmat(sqrt(sum(dT.*dT,2)),1,3);
N=dT./m; B=cross(T,N);
plot3(x,y,z,'color',0.5*[1 1 1])
axis([-4 4 -4 4 0 2.5])
hold on, grid on, pbaspect([1 1 1])
set(gca,'CameraViewAngle',7)
plot3(0,0,0,'r'), plot3(0,0,0,'color',[0 0.5 0])
plot3(0,0,0,'b')
legend('Curve','Tangent','Normal','Binormal',2)
ndx=1:4:length(x); R=R(ndx,:);
arrow3(R,R+1.4*T(ndx,:),'r',0.9)
arrow3(R,R+1.4*N(ndx,:),'e',0.9)
arrow3(R,R+0.4*B(ndx,:),'b',0.9)
hold off, view(-50,5)
set(gcf,'renderer','zbuffer')


Example 14. Frenet Frames

Named Colors

Example 15. Named Color Table

arrow3('colors',0.4) % 24 named colors with 44 adjustable shades


Example 15. Named Color Table

Color Equivalencies
ColorOrder            Arrow3	Simulink          Arrow3
Color1		Blue	LightBlue		aZure
Color2		Evergreen	DarkGreen		Asparagus
Color3		Red	Orange		kumQuat
Color4		Sky blue	Gray		Light gray
Color5		Violet
Color6		Pear
Color7		Dark gray

转载于:https://www.cnblogs.com/Kermit-Li/p/4071830.html