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 Jun 2 awarded Nice Answer Apr 30 awarded Necromancer Apr 30 awarded Nice Answer Apr 30 revised Generating convex polyhedron from face planes? added 50 characters in body Apr 30 comment Generating convex polyhedron from face planes? @level1807 Good catch! Although I haven't tested it, it looks like a bug to me--evidently from a typographical error. The intention was to to compare the chopped values to zero, not to chop the results of a floating point comparison (which makes little sense anyway). I will go ahead and modify the code in this answer. Thanks again. Apr 30 comment Generating convex polyhedron from face planes? @level1807 I cannot say: as you can see from my example, I had no trouble with $50$ faces. The possible explanations for what you are encountering could range from differences among MMA versions through floating-point errors through some kind of bug in my code. It could be related to the limitations described in the introduction to this answer. If you want to resolve this you will need to find as simple as possible an example that can be reproduced and then offer it in a new question. Good luck! Feb 6 comment Plot a 2D vector path onto a surface @rm-rf Thank you for the tip and the kind words. I am over-extended moderating two other SE sites. Although both have elected two more moderators in the interim, the work is still too much. I hope to return here at some point. Jan 17 awarded Yearling Jan 16 comment How to check if a 3D point is in a planar polygon? @Rainer Assuming the points are very close to coplanar, the smallest eigenvalue will be close to zero and much smaller than the other two. The eigenvectors associated with the other eigenvalues--that is, the first two principal components--thereby span a plane passing close to most of the points. This gives two solutions: (1) The cross product of the first two principal components will be a normal vector for that plane. (2) The third principal component will be orthogonal to the other two, whence it too is a normal vector for the plane. Nov 7 comment NMinimize usage @Frederik You are right: I made that typo early on and because everything worked, I did not catch it. Your suggestion $x = 1+y^2$ accomplishes what was intended and everything goes through as planned. Thank you for reading this post so carefully and well! Nov 7 awarded Nice Answer Oct 24 comment Insert $+$, $-$, $\times$, $/$, $($, $)$ into $123456789$ to make it equal to $100$ @xzczd Thank you! That is a useful insight and looks to be a likely explanation for the failure. Oct 5 awarded Nice Answer Aug 24 awarded Good Answer Aug 3 awarded Nice Answer Jul 6 awarded Nice Answer Jun 12 awarded Good Answer Jun 11 awarded Enlightened Jun 11 awarded Nice Answer May 24 comment AstronomicalData and Planetary Heliocentric (x,y,z) Velocity Components +1 Consider a central difference instead: it should be more accurate. It makes a substantial difference, by the way: it affects the third sig. fig. in your example, because it reflects the net planetary acceleration during the course of 12 hours.