#include "TGraphErrors.h"
#include "TGraph.h"
#include "TF1.h"

void example04(){

	TVirtualFitter::SetDefaultFitter("Minuit");
	TGraphErrors *data = new TGraphErrors("dataset1.dat","%lg %lg %lg");

	double xmin = myData->GetX()[0];
	double xmax = myData->GetX()[ myData->GetN()-1 ];

	TF1 *myModel = new TF1("oscillation","[0]*x+[1]",xmin,xmax); 

	myData->Fit(myModel);

	gMinuit->SetErrorDef(1); 
	TGraph *cont_1s = (TGraph*) gMinuit->Contour(100,0,1);

	gMinuit->SetErrorDef(4);
	TGraph *cont_2s = (TGraph*) gMinuit->Contour(100,0,1);

	double cl = 0.95;
	int N=100;

	TGraphErrors *band = new TGraphErrors(N);
	
	for (int i=0;i<N;i++) band->SetPoint(i, i*(xmax-xmin)/(N-1.), 0);
	
	(TVirtualFitter::GetFitter())->GetConfidenceIntervals(band,cl);
	
	band->SetFillColor(kOrange-2);
	band->Draw("A3");

	myData->SetMarkerStyle(kFullCircle);
	myData->SetMarkerColor(kBlue+2);
	myData->Draw("PZ same");
}