Plot ellipsoid with only principal section lines

I have always used the Matlab function ellipsoid as follows:

[X,Y,Z] = ellipsoid(0,0,0,1,2,3,16);

figure
surf(X,Y,Z,'facecolor','none')
axis equal; grid off;

And it gives the following image:

I'd like to plot an ellipsoid like the following one:

Is there a way on Matlab?

Answer 1

[Adam Danz]

This solution produces a white ellipsoid surface with transparency so that lines in the back are faded. Then it adds the major circumferential lines by computing them manually.

% Define center and radii
cnt = [0 0 0]; % center point, row vec
xyzR = [1 2 3]; % radii, row vec

% Compute major circumferential lines.
th = linspace(0,2*pi,150)'; % column vec
ex = @(r,c)c+r*cos(th); % r=radius (scalar), c=center (Scalar)
ey = @(r,c)c+r*sin(th); % r=radius (scalar), c=center (Scalar)
ez = @(c)repmat(c,size(th)); % c=center (scalar)

xy = [ex(xyzR(1),cnt(1)), ey(xyzR(2),cnt(2)), ez(cnt(3))        ];
xz = [ex(xyzR(1),cnt(1)), ez(cnt(2)),         ey(xyzR(3),cnt(3))];
yz = [ez(cnt(1)),         ey(xyzR(2),cnt(2)), ex(xyzR(3),cnt(3))];

% Plot white, partially transparent ellipsoid
clf
[X,Y,Z] = ellipsoid(cnt(1),cnt(2),cnt(3),xyzR(1),xyzR(2),xyzR(3),16);
sh = surf(X,Y,Z,'facecolor','w','EdgeColor','none','FaceAlpha',.33); 
hold on; 
xlabel('x'); ylabel('y'); zlabel('z')

% Add circumferential lines
plot3(cnt(1), cnt(2), cnt(3), 'ko','MarkerSize',8,'MarkerFaceColor','k')  % center point
lw = 2; % line widths
plot3(xy(:,1), xy(:,2), xy(:,3), 'k-','LineWidth',lw)
plot3(xz(:,1), xz(:,2), xz(:,3), 'k-','LineWidth',lw)
plot3(yz(:,1), yz(:,2), yz(:,3), 'k-','LineWidth',lw)

% Add origin lines
endPoints = (cnt + xyzR).*[-1 -1 1];
plot3([cnt(1),endPoints(1)],cnt([2,2]), cnt([3,3]), 'b-','LineWidth',lw)
plot3(cnt([1,1]), [cnt(2),endPoints(2)],cnt([3,3]), 'b-','LineWidth',lw)
plot3(cnt([1,1]), cnt([2,2]),[cnt(3),endPoints(3)], 'b-','LineWidth',lw)

axis equal
view(-60, 23)
grid off

edit: no content change; cleaned up code by aligning xy, xz, yx matrices.

[chicken vector]

This is very good. Somehow I did not think about drawing the lines manually.

Thank you very much!

[Adam Danz]

I'm still not convinced it's the smoothest solution but it does the job. I'd be happy to see alternatives.