// copied from PhysicsAnalysis/TopPhys/TopPhysUtils/TopElectronSFUtils/trunk/electron_SF_EPS.h on 21 June 2011 at 3pm UK time
#ifndef electron_SF_VV_h
#define electron_SF_VV_h

/****************************************************************************
 * electron_SF_EPS.h                                                        *
 *                                                                          *
 * Simple functions which return data/MC scale factors                      *
 * given a electron's eta 						    *
 * Also functions for corresponding uncertainties.                          *
 *                                                                          *
 * double ele_ID_SF(double et, double ET)                   	            *
 * double ele_ID_SF_err(double eta, double ET)               	      	    *
 * double ele_reco_SF();                                    	            *
 * double ele_reco_SF_err();                                 	      	    *
 * double ele_recoID_SF(double eta, double ET);             	            *
 * double ele_recoID_SF_err(double eta, double ET);          	      	    *
 * double ele_trigger_SF();                                 	            *
 * double ele_trigger_SF_err();                              	      	    *
 *                                                                          *
 * History                                                                  *
 *         26 Jan 2011 -- created by S. Caughron                            *   
 *         05 May 2011 -- updated for pLHC                                  *   
 *         14 May 2011 -- more pLHC updates                                 *   
 *         20 Jun 2011 -- updated for EPS                                   *   
 ***************************************************************************/

#include <iostream>
#include <math.h>

// forward declaration of functions

double ele_WZ_trigger_SF(double eta);
double ele_WZ_trigger_SF_err(double eta);

double ele_WZ_trigger_Eff_MC(double eta);
double ele_WZ_trigger_Eff_data(double eta);


double ele_WZ_trigger_Eff_MC(double eta) // for now just assuming 99.5% efficiency for MC until new numbers
{
    double ele_eta = eta;
    int etaI=-1;

    const double etabins[18] = {-2.47,-2.37,-2.01,-1.81,-1.37,-1.15,-0.8,-0.6,-0.1,0,0.1,0.6,0.8,1.15,1.52,1.81,2.01,2.37};
    const double Eff_MC_matrix[18] = {0.995, 0.995, 0.995, 0.995, 0.995, 0.995,
				 0.995, 0.995, 0.995, 0.995, 0.995, 0.995,
				 0.995, 0.995, 0.995, 0.995, 0.995, 0.995};
    const double etamax = 2.47;
    const double etacrack[2] = {1.37,1.52};
    if ( fabs(ele_eta) > etamax || (fabs(ele_eta) > etacrack[0] && fabs(ele_eta) < etacrack[1]) )  // check forward, crack regions
      return 1.0;       
    else {           
      for (int i=17; i>=0; i--){    // find eta index
	if ( ele_eta > etabins[i] ) {
	  etaI = i;
	  break;
	}
      }
      return Eff_MC_matrix[etaI];
    } //else
    return 0;
}

double ele_WZ_trigger_Eff_data(double eta)
{
    double ele_eta = eta;
    int etaI=-1;

    const double etabins[18] = {-2.47,-2.37,-2.01,-1.81,-1.37,-1.15,-0.8,-0.6,-0.1,0,0.1,0.6,0.8,1.15,1.52,1.81,2.01,2.37};
    const double Eff_data_matrix[18] = {0.9607, 0.9690, 0.9793, 0.9818, 0.9920, 0.9847,
				 0.9798, 0.9880, 0.9862, 0.9878, 0.9873, 0.9921,
				 0.9865, 0.9907, 0.9932, 0.9733, 0.9737, 0.9741};
    const double etamax = 2.47;
    const double etacrack[2] = {1.37,1.52};
    if ( fabs(ele_eta) > etamax || (fabs(ele_eta) > etacrack[0] && fabs(ele_eta) < etacrack[1]) )  // check forward, crack regions
      return 1.0;       
    else {           
      for (int i=17; i>=0; i--){    // find eta index
	if ( ele_eta > etabins[i] ) {
	  etaI = i;
	  break;
	}
      }
      return Eff_data_matrix[etaI];
    } //else
    return 0;
}


// For trigger SFs
double ele_WZ_trigger_SF(double eta)
{
    double ele_eta = eta;
    int etaI=-1;

    const double etabins[18] = {-2.47,-2.37,-2.01,-1.81,-1.37,-1.15,-0.8,-0.6,-0.1,0,0.1,0.6,0.8,1.15,1.52,1.81,2.01,2.37};
    const double SFmatrix[18] = {0.9655, 0.9739, 0.9842, 0.9867, 0.9970, 0.9896,
				 0.9847, 0.9930, 0.9912, 0.9928, 0.9923, 0.9971,
				 0.9915, 0.9957, 0.9982, 0.9782, 0.9786, 0.9790};
    const double etamax = 2.47;
    const double etacrack[2] = {1.37,1.52};
    if ( fabs(ele_eta) > etamax || (fabs(ele_eta) > etacrack[0] && fabs(ele_eta) < etacrack[1]) )  // check forward, crack regions
      return 1.0;       
    else {           
      for (int i=17; i>=0; i--){    // find eta index
	if ( ele_eta > etabins[i] ) {
	  etaI = i;
	  break;
	}
      }
      return SFmatrix[etaI];
    } //else
    return 0;
}

// For trigger SF uncertainties (symmetric)
double ele_WZ_trigger_SF_err(double eta)
{

    double ele_eta = eta;
    int etaI=-1;

    const double etabins[18] = {-2.47,-2.37,-2.01,-1.81,-1.37,
							    -1.15,-0.8,-0.6,-0.1,0,0.1,0.6,0.8,1.15,
							    1.52,1.81,2.01,2.37};

	const double errmatrix[18] = {0.0065, 0.0059, 0.0043, 0.0043, 0.0058, 0.0046,
								 0.0052, 0.0040, 0.0042, 0.0041, 0.0040, 0.0041,
								 0.0046, 0.0041, 0.0043, 0.0067, 0.0043, 0.0098};
								   
	const double etamax = 2.47;
	const double etacrack[2] = {1.37,1.52};

    if ( fabs(ele_eta) > etamax || (fabs(ele_eta) > etacrack[0] && fabs(ele_eta) < etacrack[1]) )  // check forward, crack regions

        return 1.0;       

    else {           
        
        for (int i=17; i>=0; i--){    // find eta index
            if ( ele_eta > etabins[i] ) {
                etaI = i;
                break;
            }
        }

        return errmatrix[etaI];

    } //else

    return 0;

}

#endif