Passing plotting options to TMultigraph in jsroot

ROOT
1

I am using jsroot for plotting several plots. I use Multigraph.

I define a Multigraph with:

var mgraph = JSROOT.CreateTMultiGraph(obj);

where I add a TGraph obj. Then I want to add other TGraphs:

  • I tried mgraph.Add(ojb2), but it complained.Then I used:

mgraph[‘fGraphs’].arr.push(obj2);

following some other post, and it works:

However, I cannot figure out how to add the options to plot obj1 or ojb2. I want to plot obj with a line (histo) and obj2 with makers (“p”).

Any help would be appreciated.

Thanks,

Pablo Yepes

2

Hi,

See for example: root.cern.ch/js/latest/demo/multigraph.htm

[code] var npoints = 20;
var xpts=[];
var ypts=[];
for (var i=0; i<npoints; i++) {
switch(cnt%2) {
case 1 : xpts.push(i); ypts.push(5i); break;
default: xpts.push(i); ypts.push(i); break;
}
}
var graph1 = JSROOT.CreateTGraph(npoints, xpts, ypts);
graph1.fLineColor = 2;
graph1.fMarkerSize = 2;
xpts = [];
ypts = [];
for (i=0; i<npoints; i++) {
switch(cnt%2) {
case 1 : xpts.push(i); ypts.push(ii); break;
default: xpts.push(i); ypts.push(Math.sqrt(i)); break;
}
}
var graph2 = JSROOT.CreateTGraph(npoints, xpts, ypts);
graph2.fLineColor = 3;
graph2.fMarkerSize = 2;

     var mgraph = JSROOT.CreateTMultiGraph(graph1, graph2);
     mgraph.fTitle = "Drawing " + cnt++;
     
     // set fixed Y-range if required
     // mgraph.fMinimum = 0;
     // mgraph.fMaximum = 400;
     
     JSROOT.redraw('object_draw', mgraph);[/code]

Cheers, Bertrand

3

Hi,

If you need to set draw options for TGraph objects,
you need to construct TMultiGraph object yourself.

If you look in the JSROOT source code, it is not that difficult:

github.com/linev/jsroot/blob/ma … 1399-L1404

In your case:

      var mgraph = JSROOT.Create("TMultiGraph");
      mgraph.fGraphs.Add(graph1, "L");
      mgraph.fGraphs.Add(graph2, "P");

I hope, this will help.

Regards,
Sergey