Different y axis default range in batch mode

[kihjos]

The following code gives the first image below when run as given, but when I comment out the ROOT.gROOT.SetBatch(True) line it gives the second image below. As seen, they have different y-axis ranges. Is this something that happens not just for me, and is it considered a bug? I hoped to get the same results when running in batch mode or not (usually it works like that, not in this case for me).

import ROOT

ROOT.gStyle.SetCanvasPreferGL(True)
ROOT.gROOT.SetBatch(True)

graphs = ROOT.TMultiGraph()
canvas = ROOT.TCanvas()

graph = ROOT.TGraphAsymmErrors()
graph.SetFillColorAlpha(ROOT.kRed, 0.1)
graph.SetFillStyle(1001)
graph.SetPoint(0,3,1)
graph.SetPointError(0,0,0,2,0)
graph.SetPoint(1,5,1)
graph.SetPointError(1,0,0,2,0)

graphs.Add(graph, "3")

graphs.Draw("A")
graphs.GetXaxis().SetLimits(0, 6)

canvas.Modified()
canvas.Update()
canvas.SaveAs("test.png")

---

ROOT Version: 6.19.01
Platform: Ubuntu 18.04
Compiler: gcc 7.4
Python: 3.6.8

---

[StephanH]

Hi,

again I invite @couet to help here.

[couet]

I see it is connected to the fact you do SetCanvasPreferGL();
Do you really need it ?

{
///   gStyle->SetCanvasPreferGL(kTRUE);
   gROOT->SetBatch(kTRUE);

   auto graphs = new TMultiGraph();
   auto canvas = new TCanvas();

   auto graph = new TGraphAsymmErrors();
   graph->SetFillColorAlpha(kRed, 0.1);
   graph->SetFillStyle(1001);
   graph->SetPoint(0,3,1);
   graph->SetPointError(0,0,0,2,0);
   graph->SetPoint(1,5,1);
   graph->SetPointError(1,0,0,2,0);

   graphs->Add(graph, "3");

   graphs->Draw("A");
   graphs->GetXaxis()->SetLimits(0, 6);

   canvas->Modified();
   canvas->Update();
   canvas->SaveAs("c1.png");
}

[kihjos]

To set the opaqueness of the color using SetFillColorAlpha() I believe it is needed.

[couet]

Ah ok. Yes on some machines. PDF has it on all machines.
So I am not sure why the range change when SetCanvasPreferGL() is on.