Bug in the graphics display of velocity in the track/route statistics?

[hans1]

I'm a bit puzzled about the shape of the velocity curve displayed, when I call track statitics.

I put the Samsung S9 smartphone (Android 10) into my car, started ORUXMAP's tracking and drove a highway at constant velocity of 50km/h using the electronic speed control for more than 10km. During this trip,  I continuously checked the measured speed not only with my car's tachometer but also digital numbers displayed by ORUXMAP's Trip-Computer.  The speed was verified by both tools to be continuous in a range of 50,0 +-0,5km/h.

• At the end of the trip I looked at the stored route's statistics, splitting the trip into a big number of segments. The table confirmed, that I never left the speed range of 50,0 +-0,5km/h. So far no surprise.
  



• !! But activating the graphics displaying the speed. I saw a curve undulating between 48km/h and 57km/h. !!
  

So I'm a bit puzzled, what happens to the speed data at their transformation into the graphic display? (Is there some postprocessing applied to the data (like smoothing) to generate the plot, behaving crazily)

Anybody out there, who ever checked the graphic display for correctness and precision?


(I did this check, because I had been puzzled by the graphic display of my speed during running, where I couldn't believe my speed was varying so much up and down during a long run)