[rrd-users] Combining Multi-RRD Datapoints in Graph

[Fernando Di Nucci]

William R. Lorenz ha scritto:
> Hi,
> 
> I'm looking to take 2-4 unique RRD files that plot the same data from 
> different perspectives (i.e. temperature readings from four different 
> sensors) and average all the data points together into one graph line.
> 
> Is there a CDEF, VDEF, or other such function that will allow me to 
> average more than one data source together for this rrdgraph purpose?
> 
> If someone could point me to the applicable section of documentation 
> and/or has an example, I'd be very appreciative.  Thanks, in advance.
> 

Hi,
try this way

if t1, t2, t3, t4 are the 4 temperatures,

CDEF:med=t1,t2,+,t3,+,t4,+,4,/

then plot

LINE1:med#FF0000........

Hope this helps