Hi Martin, thanks for the patch, I have added it.
cheers tobi Yesterday Martin Sperl wrote: > Hi! > > As promised in my libDBI Patch announcement a few days ago, I have now created > a patch with 2 new CDEFS that allow for some prediction/extrapolation of > values into the future by calculating averages of values from the previous > days/weeks. > > Here an example image of a series with the "prediction" and its uncertainty > borders: > example image for prediction > > The graph creation is achieved with: > rrdtool graph image.png --imgformat=PNG \ > --start=-7days --end=+3days --width=1000 --height=200 --alt-autoscale-max \ > DEF:value=value.rrd:value:AVERAGE:start=-14days \ > LINE1:value#ff0000:value \ > CDEF:predict=86400,-7,1800,value,PREDICT \ > CDEF:sigma=86400,-7,1800,value,PREDICTSIGMA \ > CDEF:upper=predict,sigma,3,*,+ \ > CDEF:lower=predict,sigma,3,*,- \ > LINE1:predict#00ff00:prediction \ > LINE1:upper#0000ff:upper\ certainty\ limit \ > LINE1:lower#0000ff:lower\ certainty\ limit \ > CDEF:exceeds=value,UN,0,value,lower,upper,LIMIT,UN,IF \ > TICK:exceeds#aa000080:1 > > The prediction is only valid for a few days into the future. > For longer term predictions another patch with a set of VDEFS/CDEFS is planned > that will use least square fitting of polynomials plus sums of sinuses to get > a reasonable prediction for time periods of 3 to 6 month into the future. This > will be based on some code that was written for my astronomy thesis several > years ago... > > Attached the patch, which only touches: src/rrd_rpncalc.h src/rrd_rpncalc.c > doc/rrdgraph_rpn.pod > It also contains the documentation for the 2 new CDEFS in rrdgraph_rpn - so in > case of questions regarding usage, please read the documentation in the patch. > > Please review and give feedback, so that it may get included into one of the > next releases of rrdtool. > > Thanks, > Martin > -- Tobi Oetiker, OETIKER+PARTNER AG, Aarweg 15 CH-4600 Olten, Switzerland http://it.oetiker.ch [EMAIL PROTECTED] ++41 62 775 9902 / sb: -9900 _______________________________________________ rrd-developers mailing list [email protected] https://lists.oetiker.ch/cgi-bin/listinfo/rrd-developers
