Color names in python

Newbie
1

hello, I am in lxplus (alma9) and I have an old python script that I used to plot some histograms and diagrams.
originaly I was using “from ROOT import *” but now I’ve got a message saying I need to specify what I want to import. Fine. Now I set it to “from ROOT import TH1, TBox”

This works, but if I try to set the color of the box with
box.SetFillColor(kGray)
the error I get is:
NameError: name ‘kGray’ is not defined.

I tried with “from ROOT import TH1, TBox, TColor”

but it does not work either.

Then I found the same error for the markers: kOpenCircle is not recognized :frowning:

How can I set all the colors and marker styles by name (enum)?

Thanks
Salva

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2

I would use:
box.SetFillColor(ROOT.kGray)
This should work.

Alternatively, try import TH1, kGray, ...

3

Try importing EColor (defined in ROOT: core/base/inc/Rtypes.h Source File). With ROOT 6.32.08 this works:

>>> from ROOT import TBox, EColor
>>> b = TBox(0.2,0.2,0.5,0.5)
>>> b.SetFillColor(EColor.kTeal)
>>> b.Draw()
Info in <TCanvas::MakeDefCanvas>:  created default TCanvas with name c1
>>>
4

Thanks for the tips!

Both of this options work:
from ROOT import TH1, kGray
from ROOT import TBox, EColor

But I recommend the second one (from ROOT import TBox, EColors) as will have all colors in hand.

Thanks
Salva

5

Hi! FYI, in the upcoming ROOT 6.36, you will be able to simply use strings like "kBlack":