How is the dataindex from the datacursormode calculated?

I'm trying to convert a MATLAB code for a GUI into python pyqt5 GUI. It seems like python doesn't really have a datacursormode like that in MATALB.

What I would do in MATLAB is

1. activate the datacursor mode
2. pick a point from the plot
3. obtain the dataindex
4. update the plot based on that data index

I think I would have to figure out how the dataindex from datacursormode in MATLAB is calculated and make another code for that in python. Is there a documentation that explains how the dataindex is calculated or some other source that I could get some help?

Answer 1

[Matt J]

In a 2D plot, the dataindex i is almost certainly the one such that XData(i),YData(i) is closest to where you clicked.