TRatioPlot multiple ratios

[Michele_Selvaggi]

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ROOT Version: 5.10
Platform: Slc6
Compiler:

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Hi,

I have tried to follow the instructions here:

Compare several histograms with TRatioPlot

Hello, I’d like to compare several histograms to a reference histogram and I started doing this using TRatioPlot (which I find a great update in the latest ROOT versions). I see that the TRatioPlot only supports two histograms in the constructor: TRatioPlot (TH1 *h1, TH1 *h2, Option_t *option="pois") so I tried to define a TRatioPlot for each histogram I want to compare to the reference but, as far as I understand, I can’t Draw more than one TRatioPlot on the same Canvas, e.g. (I am using py…

but it seems to me that given that the method GetLowerRefGraph() requires the TRatioPlot ratio2 to be drawn first. And If ratio2 is drawn then the whole Canvas gets messed up and the ratio2 is not drawn (h2 is however properly plotted on the upper pad). The macro I am using can be found here (*)

Thanks for your help

(*) —

/afs/cern.ch/work/s/selvaggi/public/tratio2.py

[couet]

May be you need a gPad->Update() before retrieving the lower pad.

[Wile_E_Coyote]

Try to draw these two ratio plots in two separate canvases (then extract what you need).