Hello,
I’m having trouble fitting an error function to my plotted data points on a histogram. I’ve attempted the following:
// Make a TTree from the data:
TTree *T = new TTree("ntuple","csv file data");
Long64_t nlines = T->ReadFile(TString::Format("%sdata%d.csv",dir.Data(), i),"a:b:c:d:e");
printf(" found %lld points\n",nlines);
// Develop the histogram:
TH1F *H = new TH1F("H", "b vs a; a; b", 100000, -0.00001, 0.00005);
// Draw the histogram from Tree:
T->Draw("a>>H","b","hist p");
// To see marker style/size/color options, go to: https://root.cern.ch/doc/master/classTAttMarker.html.
H->SetMarkerStyle(kFullDotSmall);
H->SetTitle("b vs a");
// TF1 *f1 = new TF1("f1","TMath::Erf(x)",-0.00005,0.00005);
TF1 *f1 = new TF1("f1","[0]*TMath::Erf((x-[1])/[2])",-0.00005,0.00005);
H->Fit("f1");
H->Draw("hist p");
gSystem->ProcessEvents();
TImage *img = TImage::Create();
img->FromPad(c);
// Save the histograms as .png images individually:
img->WriteImage(TString::Format("data%d.png",i));
T->Write();
H->Write();
That which is above is a small bit of my attempt at creating a histogram from a tree. I was hoping someone could help me with fitting, as it is not showing up on my histogram.
Also, if anyone has any suggestions as to how I could improve the code, I would be extremely grateful!
Thank you!