Is there a way the define the starting and end point of an annotation object such as an arrow in terms of the data being plotted and not as either "normalized" coordinates (x- and y-positions between 0 and 1) or a physical length measurement such as cm?
E.g. I am plotting a time from 0 to 180 s on the x-axis and a concentration between 0 and 0.1 concentration units on the y-axis. Now I would like to draw an arrow starting at 90 s, 0.04 concentration units and going to 120 s, 0.09 concentration units.
I have already considered to simply "normalize" those positions myself (e.g. 90 s/180 s = 0.5 --> x-position in normalized coordinates). This does, however, not work, since 0 and 1 refer to points in the whole figure (the window in which the plot appears) and not to the area of the plot itself.
Thanks for any input! Clemens