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I’m using mathematica 9.0 and want to draw an Ellipse in 3D. I notice that there is “Sphere”, but not ellipse... what is the easy way do draw one?

Thanks

rhermans
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david
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    Look for Ellipsoid in the documentation... – Fraccalo Jul 10 '18 at 14:42
  • as in Graphics3D[Ellipsoid[{0, 0, 0}, {4, 3, 2}]]? or Graphics3D[ Table[{Hue[RandomReal[]], Ellipsoid[RandomReal[50, {3}], RandomReal[{1, 5}, 3]]}, {100}]] – chris Jul 10 '18 at 14:43
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  • @rhermans He wrote ellipse, not ellipsoid. I do not think we should try to second guess what people mean. It is entirely reasonable to want to draw an ellipse in 3D (after all it's a conic section, it's often drawn in 3D to illustrate that). (Also, the edit made my answer look pretty stupid and prompted people to point that out.) – Szabolcs Jul 10 '18 at 16:11
  • Another way: Graphics3D[{Scale[Sphere[], {3, 1, 10}]}] – Jens Jul 10 '18 at 16:22
  • @Szabolcs You are correct, I did a very bad edit. I have reverted it now. Apologies for my mistake, I will be more careful in the future, and try to not do more than three things at the same time. – rhermans Jul 10 '18 at 16:27
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    @rhermans I did wonder if OP meant ellipse or ellipsoid because he mentions Sphere. It is entirely possible that he meant ellipsoid ... but he wrote ellipse (twice). He should clarify. – Szabolcs Jul 10 '18 at 16:29

2 Answers2

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When I wrote this answer the question clearly asked for an ellipse.

Look up ParametricPlot3D and use the equation of an ellipse.

ParametricPlot3D[{2 Cos[u], Sin[u], 0}, {u, 0, 2 Pi}]

enter image description here

Szabolcs
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  • Ellipse =!= Ellipsoid... – Jens Jul 10 '18 at 16:08
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    @Jens Of course it's not the same. The original poster wrote ellipse (not once but twice). Then someone else edited the post and changed it to ellipsoid (only after I wrote the answer). The original poster also mentioned Sphere[], so he might have meant ellipsoid, but I am not going to play that kind of guessing game. If he asked for an ellipse, he will get an ellipse from me. – Szabolcs Jul 10 '18 at 16:10
  • Sorry - didn't know this, but have been annoyed by the same issue several times before. In this case it would be a dupe of https://mathematica.stackexchange.com/q/6526/245. – Jens Jul 10 '18 at 16:16
  • Sorry, it was my fault. – rhermans Jul 10 '18 at 16:28
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ParametricPlot3D[{3 Cos[u] Cos[v], 2 Cos[u] Sin[v], 1 Sin[u]}  (*-(\[Pi]/2)<u<\[Pi]/2,0<v<2\[Pi] *), {u, -Pi/2,Pi/2}, {v, 0, 2 Pi}]

enter image description here

plots an ellipsoid!

Ulrich Neumann
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