here is a Ellipse drawn from Spline command Tangent doesn't work right on this is there a way to find the point that is the farthest X east and the farthest west X point and same North and South with Y
The farthest X point and Y point
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john.uhden wrote:Agreed, except for the interesting part.
The attachment in post #22 makes the Op's intent quite clear – that is, if the reader has a background in art. That background would probably have exposed the reader to a One Point Perspective setup, and the general technique for approximating a circle.
I know that art and CAD are not necessarily associate with each other, but that shouldn’t be the case. Certainly, we’d expect a cad operator to understand geometry. Perspective, via Camera or pencil (or AutoCAD), is manipulation of geometry. Circles, ellipses, polylines, rays, angles – we Cad jockeys eat this stuff up. The process should be interesting.
Sure, Splines are the bane of all AutoCAD users past and present, but that just because they are the new kid on the block. Once we stop picking on them we’ll see that they’re quite helpful.
@john.uhden wrote:
The Horizontal Elliptical Reinforced Concrete Pipe (HERCP) that we design is not an ellipse at all. It has two larger radii and two smaller radii that sort of look like an ellipse. All that matters is the area and wetted perimiter as a function of depth of flow within the pipe.
Eventually they will be. The discontinuity will prove failure prone, and generate unnecessary turbulence.
@john.uhden wrote:
My apologies for having an incorrect opinion.
I will try to inform the ASCE, ACI, ASTM, USACE, US Army, US Navy, US Air Force, US Coast Guard, US Air National Guard, US Dept. of the Interior, US Dept. of Veteran Affairs, USEPA, NJDEP, and other local agencies of your warning.
Surely that is not an accusation of my goading you preemptively. I'm gonna guess that it was an emoji not up to the task.
By the way, all of those agencies are well aware of the relationship between stress concentration and crack propagation. They're all also aware of the impact discontinuity has on laminar flow. You won't see a multi arc facsimile on the nose of the new fast attack submarine.
The grim reality is that the designer of the original Horizontal Elliptical Reinforced Concrete Pipe didn’t realize he had the PELLIPSE System Variable set to 1.
@stevor wrote:
How about a bounding box to make 4 lines,
then the closest point of the 'ellipse' to each LINE?
That's what Post 6 is about. But that's a rectangular/orthogonal outline, which Post 14 suggests is not what's wanted.
Kent Cooper, AIA 
@SEANT61 wrote. "The grim reality is that the designer of the original Horizontal Elliptical Reinforced Concrete Pipe didn’t realize he had the PELLIPSE System Variable set to 1.
"
I think the designer has probably been dead for at least 20 years, probably more like 40. There was no PELLIPSE even while he was alive because there was no AutoCAD nor even a computer on which to run it. Even without computers, it's sounds amazing but they built things like pyramids, bridges, tunnels, dams, and other things that have all crumbled because they weren't true ellipses, or maybe circles in some obliqued UCS.
