# How to identify a face is circle using it's vertices [closed]

Is there a way to identify whether a face is of circular shape and it's center?. All I have is the face and it's vertices.

## closed as unclear what you're asking by Hans Lundmark, Lord Shark the Unknown, KReiser, Rebellos, CesareoDec 7 '18 at 11:50

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• Are you asking, given the numerical coordinates of some points in the plane, how do you tell if they lie on a circle? If so, are you concerned about numerical imprecision? – kimchi lover Dec 6 '18 at 15:45
• Yes. I am not concerned. – Chandu Dec 6 '18 at 23:44

Given a list of $$(x_i,y_i)$$ pairs, representing points in the plain, see if you can predict $$x_i^2+y_i^2$$ with an affine function of $$(x_i,y_i)$$, by, say, least squares. If your points lie exactly on a circle, the residual sum of squares should equal 0.