I am adding a vertical line to a ratio plot TPad and want it to go from bottom all the way up to the top of the pad. I successfully achieved this either by getting the y range via pad->GetUymin() / max() or by pad->GetRangeAxis(xmin, ymin, xmax, ymax). However, in our framework we can switch from ratio plot to signal significance plot in which case, I have some difficulties getting the range correctly. The only difference I see in the code, is that in the significance case, a TH1 is plotted to the pad via TH1 *frame = pad->DrawFrame(...) and then, its range is set as frame->GetYaxis()->SetRangeUser(0, maxValue). In this case, with my settings, the vertical line is always drawn only in (0, 1) range for both of my approaches. Is this the desired behaviour or should GetUymin() / max() and GetRangeAxis() return the true y limits?
How can I retrieve the right y range from the TH1 embedded to my pad then?
It seems ok for me but may be that’s not the problem you encounter:
void lineonpad() {
auto C = new TCanvas();
gPad->DrawFrame(4.,0., 10.,5.);
auto l = new TLine();
l->DrawLine(7.,gPad->GetUymin(),7., gPad->GetUymax());
}
Hi, thank you for your prompt reply. This also works for me, but in the code, the DrawFrame() is assigned to a TH1 and new range is then set to this TH1. If I add this to your code, it breaks the ranges:
void lineonpad() {
auto C = new TCanvas();
TH1 *frame = gPad->DrawFrame(4.,0., 10.,1.);
frame->GetYaxis()->SetRangeUser(0,10);
auto l = new TLine();
l->DrawLine(7.,gPad->GetUymin(),7., gPad->GetUymax());
}
void lineonpad() {
auto C = new TCanvas();
TH1 *frame = gPad->DrawFrame(4.,0., 10.,1.);
frame->GetYaxis()->SetRangeUser(0,10);
gPad->Modified(); gPad->Update();
auto l = new TLine();
l->DrawLine(7.,gPad->GetUymin(),7., gPad->GetUymax());
}
