Sujet : Re: The Circles
De : dohduhdah (at) *nospam* yahoo.com (sobriquet)
Groupes : sci.mathDate : 01. Jul 2025, 22:16:30
Autres entêtes
Organisation : A noiseless patient Spider
Message-ID : <1041j7e$3221b$2@dont-email.me>
References : 1 2 3 4 5
User-Agent : Mozilla Thunderbird
Op 01/07/2025 om 21:23 schreef Chris M. Thomasson:
On 7/1/2025 4:29 AM, sobriquet wrote:
Op 01/07/2025 om 07:16 schreef Ross Finlayson:
On 06/30/2025 11:29 AM, Chris M. Thomasson wrote:
On 6/28/2025 8:38 PM, Ross Finlayson wrote:
Oh, been a while, figure I'll post.
[...]
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An ellipse is nothing more than a circle projected in 3d? ;^)
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That's frivolous.
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An ellipse is constructible from a loop of string and two pegs.
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An image of a circle onto a plane as projected from
an incident angle via 3D: is not an ellipse, either.
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Ask your shadow.
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Looks like an ellipse to me:
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https://www.desmos.com/3d/syqqdp9cef?translucentSurfaces
:^)
An ellipse, take a parametric circle and use different x and y radii in the 2d plane. However, Think of rotating a circle in a 3d projection. It visually looks like an ellipse. So, I always found that interesting. If I take an ellipse in 2d, it has a rotated circle "counterpart" in 3d? Fair enough, kind of? ;^)
I dunno.. seems complicated because it might depend on the perspective or angle of view, which can distort things.
https://i.imgur.com/5XiKI7u.png
The Circles
Re: The Circles