How to use colors from Color Wheel?

SetFillColor(kBlue-1) returns Green color…

The color wheel was introduced in version 5.16. Move to this version or newer if you want to use the color codes from the color wheel.


ok, thank you
another question: why gStyle->SetHistLineWidth(3) doesnt work?
Line still has width=1.

I do not see any problem with gStyle->SetHistLineWidth(), ie

gStyle->SetHistLineWidth(3) TH1F h("h","h",100,-3,4) h.FillRandom("gaus",400) h.Draw()

It looks like you are calling gStyle->SetHistLineWidth after having created the histogram. If this is the case, call

h.UseCurrentStyle(); to import the current style in the histogram.


I gues the problem was that I take historgam from file

I do it after gStyle->SetHistLineWidth(3).
Anyway UseCurrentStyle(); function helped me.
Thank you