TSpline3 interpolation

Newbie
1

Hi all,

thanks to help on these forums I’m getting close to what I want or need.

I have my code displaying a histogram from root and I’m able to use a cubic spline to fit that histogram (code below).

But now I need to interpolate the cubic spline fit of the histogram. My histogram has 1001 bins and I need 1000001 points in my interpolated fit. Could somebody please throw me some hints of where to start?

When I get that going there’ll be a few more questions but they can wait. Baby steps.

Thanks people and have a good weekend.

Regards

Tim


        TH1D *h2;
	gDirectory->GetObject("EnergyLoss", h2);

	c1->cd(2);

	h2->Draw();

	TSpline3 *spline = new TSpline3(h2);

	spline->SetLineColor(kRed);
	spline->Draw("SAME");
	
  	h2->GetXaxis()->SetTitle("Depth (m)");
        h2->GetXaxis()->CenterTitle(1);  // center the name of the x-axis

	gPad->SetGridx(1);
   	gPad->SetGridy(1);

	gPad->Modified();
2

TSpline3 has an Eval function which can help you to generate these points.

3

Thanks Olivier that worked great and I’m finding my peak.