circle modelisation

[MAthou26]

Hello to all of you,

I am currently in the middle of a data analysis. I started by plotting my data. I would like to know the radius of the circle passing through some points of my curves. I was thinking of drawing corresponding circles to get the radius. I tried to draw the curves directly with the smooth function but it doesn't seem to work.
Do you have any ideas that could help me please?
Do I have to use another software ?

Thank you for your help.
Here is the example of data curves used

[nirgrahamuk]

Hi!

To help us help you, could you please prepare a reproducible example (reprex) illustrating your issue? Please have a look at this guide, to see how to create one:

FAQ: How to do a minimal reproducible example ( reprex ) for beginners

A minimal reproducible example consists of the following items: A minimal dataset, necessary to reproduce the issue The minimal runnable code necessary to reproduce the issue, which can be run on the given dataset, and including the necessary information on the used packages. Let's quickly go over each one of these with examples: Minimal Dataset (Sample Data) You need to provide a data frame that is small enough to be (reasonably) pasted on a post, but big enough to reproduce your issue. Let's say, as an example, that you are working with the iris data frame head(iris) #> Sepal.Length Sepal.Width Petal.Length Petal.Width Species #> 1 5.1 3.5 1.4 0.…