# Help with TGaxis

I have two histograms. I plotted one histogram and using TGaxis I added one new x axis on the top of the pad. My second histogram is for that new axis. How do I plot second histogram on the same pad. More specifically, My first histogram has x axis from -10 to 10 and my second histogram has x axis from 0 to 100.When I plot second histogram it is shown up to 10 not up to 100.Y axis in both is just counts. In one sense -10 of first histogram corresponds to 0 for second histogram.
This is the process I used

``````TCanvas *c= new TCanvas();
r1->Draw();//r1 is my first histogram from -10 to 10
TF1 *f1 = new TF1("f1","x",0,100);
TGaxis *A = new TGaxis(-10,25,10,25,"f1",10,"+",5);
A->Draw();
r2->Draw("hist same");//r2 is my second histogram
``````

Any Help will be appreciated.
Thank You
KB

Hello,

Could you post your full macro so that we can try to reproduce what you’re getting?

Cheers,
Jakbo

Hi Jakbo,
Here is the code.test.C (927 Bytes)

Thank You
KBUnderAllNW_VWBar18_VWPosAndTDCHistogramWithWithoutNWForGatingof12.root (10.4 KB)

Thank you! I see the problem now, actually I’m not sure if you can easily combine two x axis in the same plot. For two y axis, there is a tutorial.

@couet Are the different x axis possible?

Try (you will need to “convert” it to use histograms instead of graphs):

BTW. Maybe you simply want:

``````{
TCanvas *c = new TCanvas("c", "c");
c->DrawFrame(-10, 0., 100., 25., "My Title;My X;My Y"); // draw the frame
TF1 *f1 = new TF1("f1", "x", 0., 100.);
f1->Draw("SAME"); // draw the function
r1->Draw("HIST SAME"); // r1 is my first histogram from -10 to 10
r2->Draw("HIST SAME"); // r2 is my second histogram
}
``````
1 Like

Thank You all for your help

This topic was automatically closed 14 days after the last reply. New replies are no longer allowed.