Upper half of TGraph Polar only


I have to create polar plots as shown in the attachment. It is obviously not necessary to plot the whole range of theta from 0 to 2pi. Is there a possibility to plot only the upper half of the circle from 0 to pi?

I know that there is a way to change the polar range, but then i still get the whole circle. The only difference is that pi/2 is at ‘9 o’clock’ now and so on. So this only skews the picture.

test.pdf (43.3 KB)


have you tried:
root.cern.ch/doc/master/classTG … 65f0f5ea70

About this SetMaxPolar method, I think the description could be clearer. Maybe, you may improve it.


Thank you for your reply. Sorry that i answer so late. I tried it like this:

TGraphPolar * grP1 = new TGraphPolar(9, theta, radius, etheta, eradius); grP1->SetMaxPolar(TMath::Pi()); grP1->Draw("PE");

This had no effect at all. But I am not sure if i used SetMaxPolar correctly.

Actually TGraphPolar always draw a full circle… You wanted half of it ?

Exactly, that is what i want to do. Sorry, i might have expressed myself somewhat unclear.

So that’s not possible right now.

Nevertheless, thank you!