I need an illustration of a translucent ellipsoid so that I can also see a vector form the origin to an offset center and a vector from that point to somewhere on the surface of the ellipsoid. Something like the lovely old illustrations in Halliday and Resnick would be great but I have no artistic talent.

I have tried the usual Open Source and web based applications, including the Wikipedia recommendations on how to make illustrations for Wikipedia, and can't find a way to get what I would call textbook or tutorial quality figures that clearly illustrate what I can clumsily draw.

The old potato surface and Gauss's Law in Arfken or the stereo pairs in Morse and Feshbach are heads and shoulders above anything I have been able to get from Mathematica's online tools, or Geogebra, or other StackExhange answers etc.

Here is an illustration from Simon's Mechanics that has some of the features. It has a translucent surface and vectors and notation are visible inside. enter image description here

The case I need to draw will show 3 axis, an offset vector from the origin and a vector from the offset to a point on the surface. (It would be a sphere centered on the origin if ideal. There are three offset errors and 3 gain errors).

This may not qualify as a physics question unless I ask for the path the pencil will take to get a projection of the object onto a page. If there is a good list of apps or examples or an answer I have missed, much appreciated.

  • $\begingroup$ Can you link to an image of the kind that you would like to make? $\endgroup$ – CuriousOne Feb 8 '16 at 5:13
  • $\begingroup$ I am, too, unsure about what exactly you need, but I would prefer using error bars of any kind instead of a translucent ellipsoid. As a matter of fact, the latter always projects to an ellipse, making it harder to interpret in 3D. $\endgroup$ – dominecf Feb 8 '16 at 10:06
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    $\begingroup$ I'm voting to close this question as off-topic because it's about computer software for making duagrams $\endgroup$ – innisfree Feb 9 '16 at 8:52
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    $\begingroup$ 1. I second the motion to close the question 2. If you just want illustrate a concept without needing special values, do it by hand ! You will waste so much time if you try to find a good way to come up with a "correct" solution (i.e. one gathered from a projection of 3d objects). I would suggest inkscape. $\endgroup$ – Bort Feb 9 '16 at 9:03
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    $\begingroup$ @C.TowneSpringer I am really not that talented at arts, but this also not that difficult of a drawing.. heres a rough sketch (inkscape.. maybe 10 minutes) imgur.com/tYxDLWw . The most important advice I would give you: always do a fake lighting / shadowing. Doesnt need to be good, but still really helps the image $\endgroup$ – Bort Feb 9 '16 at 9:41

For what it's worth,

here is some Mathematica code to produce an opaque sphere (i'm plotting two nested ones so that the opacity is more clearly shown).

 a = 1; b = 2; c = 3
 ParametricPlot3D[{{b Cos[u] Sin[v], c Sin[u] Sin[v], 
   a Cos[v]}, {a Cos[u] Sin[v], b Sin[u] Sin[v], c Cos[v]}}, {u, 0, 
   2 Pi}, {v, 0, 2 Pi}, Mesh -> 5, PlotStyle -> Opacity[0.5]]

Error-bars and other objects would then need to be added using the Graphics3D wrapper.


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