Dear all, I have 2 measurement series from 2 different sensors and at different timestamps, that I do Grafana charts from, that works really nice.
Now I would like to “subtract one graph from the other and display the resulting graph” - but how to do?
The graphs I create/fill with this 2 queries:
SELECT “Temperatur” FROM “M41” WHERE (“Sensor” = ‘Beet’) AND $timeFilter
SELECT (“Wetness”) FROM “M41” WHERE (“Sensor” = ‘Feuchte’) AND $timeFilter
As mentioned, the measurements are done continuously, but at different timestamps…
Reason is to somehow “temperature-compensate” the wetness sensor (so other calculations may be wanted later)