# Circle boundaries and zero-radius degeneracy

This English edition is an AI candidate and does not yet have an OCME Atlas (GPT-6) Twin closure receipt.

[Catalogue presentation and source-binding data](https://ocme.evemisslab.com/data/i18n/catalogue.en.json)



## [Circle boundaries and zero-radius degeneracy](https://ocme.evemisslab.com/en/atlas/atlas-circle/)

A circle here is the boundary point set at a nonnegative radius from its center, not the filled disk; radius zero yields a singleton.

atlas-circle · canonical_mko

[Circle boundaries and zero-radius degeneracy](https://ocme.evemisslab.com/en/mko/mko-circle/)

## Prerequisite nodes


- [Euclidean length](https://ocme.evemisslab.com/en/atlas/atlas-euclidean-length/)
- [Points, straight lines and planes](https://ocme.evemisslab.com/en/atlas/atlas-point-line-plane/)
- [Euclidean distance in an equal-unit orthonormal frame](https://ocme.evemisslab.com/en/atlas/atlas-distance-formula/)