Managing palette with PyROOT

From: Barbara Storaci <Barbara.Storaci_at_cern.ch>
Date: Mon, 18 Feb 2008 17:21:57 +0100

Dear ROOT experts,
I am using PyROOT and I would like to modify some characteristics of the palette of my 2D histogram. I am trying to set the range of the "palette axis" and to set the number of steps in which I would like to have my palette divided. The problem is that I do not know how to convert the command:

TPaletteAxis *palette=(TPaletteAxis*) h->FindObject("palette")

in Python.  

I tried to write:

    palette = h.FindObject("palette");
    axis = palette.GetAxis()

    axis.SetWmin(0) 
    axis.SetWmax(1.5) 
    axis.SetNdivisions(10) 

where "h" is a TH2F

but I obtain the following error:
" axis = palette.GetAxis()
AttributeError: 'NoneType' object has no attribute 'GetAxis' " while in C++ palette would have pointed to an existing object.

Have you got any suggestions?
Thanks a lot

      Barbara

---

Barbara Storaci                            mailto:Barbara.Storaci_at_cern.ch
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GSM(Italy): +39.349.7785671 Received on Mon Feb 18 2008 - 17:22:01 CET