[mrtg] maths in mrtg

[Nick price]

For my incoming mains power supply I have a monitor box that gives me kVA
and kVAR values via SNMP  I need to get kW into a graph.

 

I need to do the following maths  kW=(kVA^2-kVAR^2)^0.5 how do I get mrtg to
do this

 

Many thanks in advance

 

Nick

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