[rrd-users] Quantisation issues - how do i get the math right?

Andreas Schuldei andreas+rrdtool at schuldei.org
Fri Mar 10 16:51:26 CET 2017

I changed that and am puzzled.
how do i deal with the huge offset? In that setup, the value the device
returns is ~8000, and its a 64bit ever increasing counter...

In an other thread (
that seems to deal with a similar issue,  someone recommend:

"Alternatively, you could use Absolute and reset the counter each time -
then you don't need to worry about storing the total."

I can not reset the counter in the device. Or does that person refer to
some rrdtool counter that I can reset with some clever CDEF magic?

And how will the data, which "absolute" would give me, be usable in my
case? From the documentation (
https://oss.oetiker.ch/rrdtool/tut/rrd-beginners.en.html) I understand that
I would get an slowly ascending staircase. But in what way can i use that
to emulate my incoming power? Ever increasing power from my solar panels
would be awesome, but that is not what I experienced before using rrdtool

I just got an idea that there might be some confusion about the word

I am interested in both the engergy (Energie) and the power (Leistung)
output. Currently I am dealing with the power graph. Energy is the sum (or
integral over time) of the power. So ABSOLUTE (implemented as an ever
increasing staircase) would emulate the absorbed energy, but not the power.
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