How to plot an Arc in 3D with Mathcad 15 ?

[lvl107]

Hello Everyone.
From :

How to plot an Arc in 3D with Mathcad 15 ?
Thanks in advance for your time and help.
Best Regards.
Loi.

[Werner_E]

Depends upon what is known from the arc.

But basically you would first have to find a parameter representation and then use CreateSpace().

[lvl107]

I greatly appreciate your time and explanation, Werner. 🤔 🙄

Sorry,.. my question is not clear :

How to plot an Arc go through 4 points ? ( start-point : red , end-point : orange )

Best regards.

Loi.

[Werner_E]

What kind of "arc"? You sure can't demand it to be part of a circle (which usually is defined by just three points)

In your example, by chance (?) all four points lie in a plane and on the same circle arc (with center in the origin). But this is not normally the case with four arbitrary points in space.
So if you want to envisage an arc of a circle, you must only specify three points, not four!

[lvl107]

Thanks for reminding me 😂 Werner . Now I realize that I must only specify three points for an Arc.

( start-point : red , end-point : orange )

Best Regards.

[ttokoro]

Check this!

Mathcad Community Challenge July 2022 - Area of a ... - PTC Community

[Werner_E]

Hmm, but what if the points are not given in the expected order, that is P and S are not start and end point of the arc?

And what if the arc has an angle of pi or more?

😈

[Werner_E]

Was not allowed to add the pic in the previous posting ...
Pic show the three possible ways for an arc through 3 points and also the case of collinear points (or identical points) where the "arc" actually is a straight line.

[ttokoro]