I want to Draw TF1 object with fitting errors.
What I want to do is
Fit the TH1 histogram by TF1 function, and then draw the fit function with fitting errors like TGraphPainter.
I tried Draw->(“e”) but this option draws with statistical error.
root [0] hpx->Fit("gaus");
Info in <TCanvas::MakeDefCanvas>: created default TCanvas with name c1
FCN=116.145 FROM MIGRAD STATUS=CONVERGED 52 CALLS 53 TOTAL
EDM=6.90265e-09 STRATEGY= 1 ERROR MATRIX ACCURATE
EXT PARAMETER STEP FIRST
NO. NAME VALUE ERROR SIZE DERIVATIVE
1 Constant 7.95916e+02 6.15041e+00 2.66657e-02 2.24892e-05
2 Mean -1.08164e-02 6.33665e-03 3.34812e-05 -1.86751e-03
3 Sigma 9.97964e-01 4.42145e-03 6.38273e-06 7.29629e-02
root [1] hpx->Draw("E")
root [2]
As far as I understand it, he wants to draw the FITTED FUNCTION WITH ITS UNCERTAINTIES / “ERRORS” (estimated from the fit errors), not the histogram -> i.e. something like the “best fit” plus the “± 1 sigma band”.
I checked fit result but it is valid and its status is converged.
TBinomialEfficiencyFitter doesn’t support GetCovarianceMatrix and GetConfidenceIntervals ?