# How to Draw an ellipsoid between two 3d coordinates

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yaacov yehuda-zada on 25 Jul 2021
Commented: darova on 27 Jul 2021
Hi, I want to draw a 3d ellipsoid between two 3d coordinates x1,y1,z1 and x2,y2,z2. The ellipsoid need to be rotated so its top and buttom touch the coordinates. It should have height of r derived from square root and thickness of r/10.Any help please.so far I manage to draw the ellipsoid using ellipsoid() and draw it using surf in the center of axis. I dont know how to calculate and add the required angles to rotate it and the offset.Thanks.

darova on 26 Jul 2021
Use rotate to rotate the ellipsoid
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darova on 27 Jul 2021
Use cart2sph
p1 = [1 2 1]; % first point
p2 = [2 5 1]; % second point
[az,el,r] = cart2sph(p2-p1); % find two angles and distance

Matt J on 26 Jul 2021
Edited: Matt J on 26 Jul 2021
Another way would be to use the ellipsoidalFit.groundTruth method in this File Exchange submission.
P1=[x1,y1,z1]; P2=[x2,y2,z2];
center=(P1+P2)/2;
r=norm(P2-P1)/2;
ABC=[r, r/10 , r/10];
[az,el,~]=cart2sph(x2-x1,y2-y1,z2-z1);
plot( ellipsoidalFit.groundtruth([],center,ABC,[az,-el,0]*180/pi) );