#include <stdio.h>
#include <iostream>
#include <fstream>
#include <string>
#include <TLegend.h>
#include <TMath.h>


using namespace std;

#include <TCanvas.h>
#include <TH1.h>
#include <TF1.h>
#include <TFile.h>
#include <TTree.h>
#include <TChain.h>
#include <TNtuple.h>
#include <TLegend.h>



#include "TGraphErrors.h"
#include "Fit/Fitter.h"
#include "Fit/BinData.h"
#include "Fit/Chi2FCN.h"
#include "TList.h"
#include "Math/WrappedMultiTF1.h"
#include "HFitInterface.h"
#include "TCanvas.h"
#include "TStyle.h"
#include "TSpline.h"


 
 

    
   Double_t spline_4nodes(Double_t *x, Double_t *par)
   {
   //Fit parameters:
   //par[0-3]=X of nodes (to be fixed in the fit!)
   //par[4-7]=Y of nodes
   //par[8-9]=first derivative at begin and end (to be fixed in the fit!)
   
   Double_t xx = x[0];

   Double_t xn[3] = { par[0], par[1], par[2] };
   Double_t yn[3] = { par[3], par[4], par[5] };

 

   TSpline3 sp3("sp3", xn, yn, 3,"b1e1_eval");

   return sp3.Eval(xx);
   }



void pauli_EATM(){

 


   const int pts = 3;

   Double_t x_C6[pts] = {-1.4343,-0.172143, -0.999988};
   Double_t y_C6[pts] = { 178804, 205230, 191276};

   
   TSpline3 sp_eval_see6("sp_eval_see6", x_C6, y_C6, pts,"b1e1", 0, 0);
  

  
     
     int fit_pts_x_y_dy_dx = 6;
     
     float xmin = -1.1, xmax = 1.1; 

     TCanvas* danny1 = new TCanvas ("danny1", "Interpolation", 600, 400); 

 
     TF1 *f_splineC6 = new TF1("f_splineC6", spline_4nodes, xmin, xmax, fit_pts_x_y_dy_dx); // npars = 2*nodes+2
  
     f_splineC6->SetParameter(0, x_C6[0]);
     f_splineC6->FixParameter(0, x_C6[0]);
     
     f_splineC6->SetParameter(1, x_C6[1]);
	   f_splineC6->FixParameter(1, x_C6[1]);
	   
     f_splineC6->SetParameter(2, x_C6[2]);
	   f_splineC6->FixParameter(2, x_C6[2]);
	   
     f_splineC6->SetParameter(3, y_C6[0]);
	   f_splineC6->FixParameter(3, y_C6[0]);
	   
     f_splineC6->SetParameter(4, y_C6[1]);
	   f_splineC6->FixParameter(4, y_C6[1]);
	   
     f_splineC6->SetParameter(5, y_C6[2]);
     f_splineC6->FixParameter(5, y_C6[2]);
 
     f_splineC6->GetXaxis()->SetRangeUser(-1.1, 1.1);
     f_splineC6->GetXaxis()->SetTitle("cos(#theta)");
     f_splineC6->GetYaxis()->SetTitle("C6 (meV #AA^{6})");
      f_splineC6->GetYaxis()->SetRangeUser(184000,210000);
     f_splineC6->SetLineColor(14);
     f_splineC6->SetLineWidth(3);
     f_splineC6->SetMarkerStyle(22);
     f_splineC6->SetTitle ("Fit C6 vs cos(#theta)");
     f_splineC6->Draw ("L");

      double angles[20] = {cos(0*TMath::Pi()/180.),
                      cos(15*TMath::Pi()/180.),
                      cos(30*TMath::Pi()/180.),
                      cos(45*TMath::Pi()/180.),
                      cos(60*TMath::Pi()/180.),
                      cos(65*TMath::Pi()/180.),
                      cos(70*TMath::Pi()/180.),
                      cos(75*TMath::Pi()/180.),
                      cos(80*TMath::Pi()/180.),
                      cos(85*TMath::Pi()/180.),
                      0*cos(90*TMath::Pi()/180.),
                      cos(95*TMath::Pi()/180.),
                      cos(100*TMath::Pi()/180.),
                      cos(105*TMath::Pi()/180.),
                      cos(112.5*TMath::Pi()/180.),
                      cos(120*TMath::Pi()/180.),
                      cos(135*TMath::Pi()/180.),
                      cos(150*TMath::Pi()/180.),
                      cos(165*TMath::Pi()/180.),
                      cos(179.6*TMath::Pi()/180.) 
                         };

    double Csix[20] = {sp_eval_see6.Eval(cos(0*TMath::Pi()/180.)) ,
                       sp_eval_see6.Eval(cos(15*TMath::Pi()/180.)) ,
                       sp_eval_see6.Eval(cos(30*TMath::Pi()/180.)) ,
                       sp_eval_see6.Eval(cos(45*TMath::Pi()/180.)) ,
                       sp_eval_see6.Eval(cos(60*TMath::Pi()/180.)) ,
                       sp_eval_see6.Eval(cos(65*TMath::Pi()/180.)) ,
                       sp_eval_see6.Eval(cos(70*TMath::Pi()/180.)) ,
                       sp_eval_see6.Eval(cos(75*TMath::Pi()/180.)) ,
                       sp_eval_see6.Eval(cos(80*TMath::Pi()/180.)) ,
                       sp_eval_see6.Eval(cos(85*TMath::Pi()/180.)) ,
                       sp_eval_see6.Eval(cos(90*TMath::Pi()/180.)) ,
                       sp_eval_see6.Eval(cos(95*TMath::Pi()/180.)) ,
                       sp_eval_see6.Eval(cos(100*TMath::Pi()/180.)) ,
                       sp_eval_see6.Eval(cos(105*TMath::Pi()/180.)) ,
                       sp_eval_see6.Eval(cos(112.6*TMath::Pi()/180.)) ,
                       sp_eval_see6.Eval(cos(120*TMath::Pi()/180.)) ,
                       sp_eval_see6.Eval(cos(135*TMath::Pi()/180.)) ,
                       sp_eval_see6.Eval(cos(150*TMath::Pi()/180.)) ,
                       sp_eval_see6.Eval(cos(165*TMath::Pi()/180.)) ,
                       sp_eval_see6.Eval(cos(179.6*TMath::Pi()/180.))  
                         };

 	
	
      TGraph *  graph1 = new TGraph(20, angles, Csix);
      graph1->SetMarkerSize(1);
	   graph1->SetMarkerColor(kRed);	 
	   graph1->SetMarkerStyle(20);
     graph1->SetLineColor(0);
     graph1->SetLineWidth(0);
     graph1->Draw("SAME LP");
     
    double why ;
    
	    cout <<  f_splineC6->Eval(cos(179.6*TMath::Pi()/180.)) >> endl;
     


}