Calligraphic symbols

ROOT
1

Dear all,

we’re trying to write a calligraphic R (\cal{R} in LateX) in the title of a histogram. I understand that’s currently not possible, but would be happy to be proven wrong.

I’ve seen old messages requesting this, but haven’t seen the solution. I did find a promise that it might be possible to do this in ROOT 6.0, but we need a solution on the time scale of days, rather than weeks.

If there is no solution to this problem in ROOT, we may simply post-process the PS file. The calligraphic R is actualy not part of the /symbol set either, so if anyone knows how to introduce the symbol in the PS file by hand, that’s very welcome…

Regards, Marcel

2

Actually it is possible now with the new class TMathText.
Have a look at: $ROOTSYS/tutorials/graphics/tma*.C

It is in version 5.34… I do not see doc yet on the reference manual online. I will check.

3

Hi Marcel,

As mentioned by Olivier, this should be possible in TMathText, and using “\mathscr{R}” (just like TeX).

Note that in TeX nomenclature, there is a distinction between calligraphic/\mathcal (brushstroke) and script/\mathscr (metallic quill/English script). Because Unicode has script but no brushstroke code points, only \mathscr is implemented.

Best,

Yue Shi Lai

4

You will only need to define your histogram title like:

"Histogram title with \\mathscr{R} inside"
5

See
root.cern.ch/root/html534/TMathText.html
and
root.cern.ch/root/html534/TLatex.html#L14

6

Hi,
I’m having problems in PyROOT (ROOT 6.24/06). In a TMultiGraph I write:

mgGraphs[z].GetXaxis().SetTitle("\\mathscr{O}")

And I get:
3

7

It works for me:

auto l = new TLatex(.5,.5,"Histogram title with \\mathscr{0} inside");
l->Draw();

Screenshot 2022-02-21 at 07.49.29

8

Not sure how to implement that as a TMultiGraph axis label

9 
{
   TGraph *g[3];
   Double_t x[10] = {0,1,2,3,4,5,6,7,8,9};
   Double_t y[10] = {1,2,3,4,5,5,4,3,2,1};
   TMultiGraph *mg = new TMultiGraph();
   for (int i=0; i<3; i++) {
      g[i] = new TGraph(10, x, y);
      g[i]->SetMarkerStyle(20);
      g[i]->SetMarkerColor(i+2);
      for (int j=0; j<10; j++) y[j] = y[j]-1;
      mg->Add(g[i]);
   }
   mg->Draw("APL");
   mg->GetXaxis()->SetTitle("E_{#gamma} (GeV)");
   mg->GetYaxis()->SetTitle("Coefficients");

   // Change the axis limits
   gPad->Modified();
   mg->GetXaxis()->SetLimits(1.5,7.5);
   mg->SetMinimum(0.);
   mg->SetMaximum(10.);
   mg->GetXaxis()->SetTitle("Histogram title with \\mathscr{0} inside")
}

BTW I do not understand why you need such fond for “0”. It will appear the same as a normal “0”

10

That is what I wrote in the first message basically.

mgGraphs[z].GetXaxis().SetTitle("\\mathscr{O}")

It is not a zero, it is a capital o (letter).

11 
{
   TGraph *g[3];
   Double_t x[10] = {0,1,2,3,4,5,6,7,8,9};
   Double_t y[10] = {1,2,3,4,5,5,4,3,2,1};
   TMultiGraph *mg = new TMultiGraph();
   for (int i=0; i<3; i++) {
      g[i] = new TGraph(10, x, y);
      g[i]->SetMarkerStyle(20);
      g[i]->SetMarkerColor(i+2);
      for (int j=0; j<10; j++) y[j] = y[j]-1;
      mg->Add(g[i]);
   }
   mg->Draw("APL");
   mg->GetXaxis()->SetTitle("E_{#gamma} (GeV)");
   mg->GetYaxis()->SetTitle("Coefficients");

   // Change the axis limits
   gPad->Modified();
   mg->GetXaxis()->SetLimits(1.5,7.5);
   mg->SetMinimum(0.);
   mg->SetMaximum(10.);
   mg->GetXaxis()->SetTitle("\\mathscr{O}")
}

Screenshot 2022-02-21 at 09.58.40
Screenshot 2022-02-21 at 09.58.401268×890 36.7 KB

12

You:

mg->GetXaxis()->SetTitle("\\mathscr{O}")

Me:

mgGraphs[z].GetXaxis().SetTitle("\\mathscr{O}") # mgGraphs[z] = ROOT.TMultiGraph()

I think there is not relevant difference in the code. Maybe PyROOT does not support this feature?

13

Does my macro works for you ?

14

Yes, using my ROOT installation works, but I seems that in Python it does not work.

15

Ok. That might be a Python issue. That’s a bit surprising to me but why not. May be @etejedor has an idea.

16

What about if you translate my macro in to Python ? does it fail too ?

17 
import ROOT

x = [0,1,2,3,4,5,6,7,8,9]
y = [1,2,3,4,5,5,4,3,2,1]

N = 3
g = {}
mg = ROOT.TMultiGraph()

for i in range(N):

    g[i] = ROOT.TGraph()
    for j in range(len(x)):
        g[i].AddPoint(x[i], y[i])
    g[i].SetMarkerStyle(20)
    g[i].SetMarkerColor(i+2)
    for j in range(len(x)):
        y[j] = y[j] -1
    mg.Add(g[i])

mg.Draw("APL")
mg.GetXaxis().SetTitle("E_{#gamma} (GeV)")
mg.GetYaxis().SetTitle("Coefficients")

ROOT.gPad.Modified()
mg.GetXaxis().SetLimits(1.5,7.5)
mg.SetMinimum(0.)
mg.SetMaximum(10.)
mg.GetXaxis().SetTitle("\\mathscr{O}")

ooo
ooo857×610 21.4 KB

I did something wrong about the graph points, but the important thing, the calligraphic O is there.

No idea why my original code does not work properly.

18

Me neither. So to is fixed. Fine.

19

I’m back again @couet . I modified your code to have a TCanvas and save the graph. Look at this:

1
11916×1018 228 KB

So the problem is not in the code, it seems that the problem comes when the canvas is printed as a pdf. Because if I save it as png, calligraphic symbol is ok.

Code here:

void TEST(){
   TGraph *g[3];
   Double_t x[10] = {0,1,2,3,4,5,6,7,8,9};
   Double_t y[10] = {1,2,3,4,5,5,4,3,2,1};
   
   TCanvas* c1 = new TCanvas();
   TMultiGraph *mg = new TMultiGraph();
   for (int i=0; i<3; i++) {
      g[i] = new TGraph(10, x, y);
      g[i]->SetMarkerStyle(20);
      g[i]->SetMarkerColor(i+2);
      for (int j=0; j<10; j++) y[j] = y[j]-1;
      mg->Add(g[i]);
   }
   mg->Draw("APL");
   mg->GetXaxis()->SetTitle("E_{#gamma} (GeV)");
   mg->GetYaxis()->SetTitle("Coefficients");

   // Change the axis limits
   gPad->Modified();
   mg->GetXaxis()->SetLimits(1.5,7.5);
   mg->SetMinimum(0.);
   mg->SetMaximum(10.);
   mg->GetXaxis()->SetTitle("\\mathscr{O}");
   
   c1->Print("test.pdf");
}
20

TMathText rendering is not implemented for the PDF output (use PostScript / Encapsulated PostScript output if you want vector graphics).

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