Iirc there was just a discussion about wording and modification of the Circle Center,Point tool.

The old wording radius was meant to provide a point on the circumference, by click or command line, what is in fact the radius.

But because of the wording users entered a single number, which is not valid for a point, and failed. Therefore it was renamed from radius to point to avoid this irritation.

I don't remember that entering the radius was removed, but don't nail me down on that.

So entering the radius with Circle Center,Point tool requires a coordinate. With a relative coordinate the radius is part of the coordinate, e.g. @0,10 or @10,0 or 0..10 or 10..0.

This was probably used in the video you mentioned. If you post a link, we can check it.

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