[metapost] Constructing ellipse from 4 points
lfinsto1 at gwdg.de
Wed Nov 2 20:10:12 CET 2005
On Wed, 2 Nov 2005, Brooks Moses wrote:
> A Google search on "ellipse construct 'four points'" finds the following links:
Aha! I just searched for "ellipse constructions" and found a lot of sites
that didn't look too promising. Thanks.
> The short form is that, to construct an ellipse, you need either five
> points, four points and a tangent line, or four points and knowledge of the
> direction of the major and minor axes.
I can get more points by finding the intersections of the plane with more
of the ellipses on the ellipsoid, and I can get as many of those as I
> Beyond that, I don't know. My guess is that finding the direction of the
> major and minor axes and using that construction is the way to go.
Thank you for your quick answer.
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