#ifdef COMPILED_ROOT
#include <stdio.h>
#include <math.h>

#include "TH1.h"
#include "TCanvas.h"
#include "TFile.h"
#include "TF1.h"
#include "TROOT.h"
#include "TApplication.h"

extern void InitGui();
VoidFuncPtr_t initfuncs[] = { InitGui, 0 };


#endif
Double_t expExp(Double_t* a, Double_t* aa);



#ifdef COMPILED_ROOT
TROOT root("doFit","doFit",initfuncs);

Int_t main(int argc, char** argv) {

  TApplication theApp("App",&argc,argv);

#endif
#ifndef COMPILED_ROOT
Int_t allFits(void) {
#endif
  Double_t p1,p2,p3;
  TF1* f1 = new TF1("expExp",expExp,0,1,4);  
  f1->SetParameters(17,0.01,5,2000);
  f1->SetParNames("1st slope","2nd Amp","2nd slope","scale fac");

  char histname[100];
  TH1F* h[55];
  Int_t i,j;
  Int_t k;
  FILE* fout = fopen("alldet_fits.dat","w");
  TFile* fin = new TFile("alldet_hists.root");
  fin->cd();
  f1->SetParameters(17,0.01,5,2000);
  f1->SetParNames("1st slope","2nd Amp","2nd slope","scale fac");
 
  TCanvas* c1 = new TCanvas("c1","c1",1);

  for(i=0 ; i<11 ; i++) {
    for(j=0 ; j<5 ; j++ ) {
      sprintf(histname,"en%2d rad%2d elastic",i+4,j+1);
      h[i*5+j] = (TH1F*)fin->Get(histname);
      h[i*5+j]->Fit("expExp","RI");
      p1 = f1->GetParameter(0);
      p2 = f1->GetParameter(1);
      p3 = f1->GetParameter(2);
      printf("%3d %3d %f %f %f\n",i+4,j+1,p1,p2,p3);
      fprintf(fout,"%3d %3d %f %f %f\n",i+4,j+1,p1,p2,p3);
    }

  }
  fclose(fout);
  return 1;
}


Double_t  expExp(Double_t* x, Double_t* par) {
  Double_t expPart1 = exp(par[0]*(x[0]-1));
  Double_t expPart2  = exp(par[2]*(x[0]-1));

  return (par[3]* (expPart1 + par[1]*expPart2));

}