I am looking for a way to select points in the following plot with an elliptical shape. There are “Box Select” and “Lasso Select”, but unfortunately these are not suitable for my purposes, as the freehand drawing of “Lasso Select” is too imprecise.
For example, in the example plot I would like to select the points in the red area with a kind of ellipse. What is the best way to do this
Hi @Flox ,
Based on link below there are just 2 selection mode that available in plotly (Box Select or select2d and Lasso Select or lasso2d).
Maybe you are interested to add drawcircle on the modebar as alternative. This button enable draw circle shape.
Here the example:
Welcome to the forums @Flox .
What do you mean by that? I guess your are referring to “too cumbersome to draw”. We had a similar topic about selecting in a circular shape instead of a box shape.
For both questions, IMHO applies the same answer: This functionality is not built in. You might try writing custom JS functions.
I could imagine workarounds in dash but it all depends on how you want to define the ellipse.
Thanks, I’ve already seen that too. It comes a bit closer to my goal, but it’s still not quite right because you can’t rotate the circle. For example, it is not possible to recreate the circle as in the plot.
On the one hand too cumbersome, on the other too imprecise. I am developing a gating interface at my university that will be used to analyze clinical cell data. Of course, it is important that the evaluations are reproducible. In my previous post there is a plot that I want to reproduce in a similar way, as this is essential for the application. Here it would of course be nice to have a circle with exact coordinates, radius and rotation instead of just points selected according to best guess.
Do you have a link for it by any chance, otherwise I’ll have to look myself to see if I can find the discussion? Would certainly be helpful 
Just for completeness. Found the other post
Circle selection tool
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