void fit1(){
	
  
	TCanvas *c1 = new TCanvas("c1","c1",800,800);

	
	// Creates a Root function based on function fitf above
	TF1 *func = new TF1("fitf","[3] + [2]*x + [0]/TMath::Sqrt(x + [1])", 50, 1400);
	
	func->SetParameter(0, -734770);
	func->SetParameter(1, 3271.56);
	func->SetParameter(2, -1.13006);
	func->SetParameter(3, 12612.6);
	func->SetParNames("a","b","c", "d");   

	const int n = 4;
	double offset = 0;

	double x[n]= {411, 779, 1089, 1299};
	double y[n]= { 182.56, 450.75, 611.58, 659.38};

   
	auto g = new TGraphErrors(n,x,y);
	g->SetMarkerStyle(53);
	g->SetMarkerSize(1.2);
	g->Fit(func);
  	g->Draw("AP");
  	
	gStyle->SetOptFit(111);
	
}