//example of macro illustrating how to superimpose two histograms
#include "TGaxis.h"
#include "TRandom.h"

#include <TGraph.h>
#include <TCanvas.h>
#include <TF1.h>
#include <TH1F.h>
#include <TMath.h>
#include <TStyle.h>

#include <iostream>
#include <fstream>
#include <string>

#include "TROOT.h"
#include "TGraphErrors.h"
#include "TLegend.h"
#include "TArrow.h"
#include "TLatex.h"

void plotfile()
{
   //example of macro illustrating how to superimpose two histograms
   //with different scales in the "same" pad.
   // To see the output of this macro, click begin_html <a href="gif/twoscales.gif" >here</a> end_html
   //Author: Rene Brun

   const Int_t n_lines = 5;
//   const Int_t n_lines = 445;

   double_t time_vals[n_lines];

   double_t volt_vals[n_lines];
   double_t volt_errs[n_lines];

   double_t curr_vals[n_lines];
   double_t curr_errs[n_lines];

   //TFile *h = new TFile("File.root","RECREATE");
//   FILE *f = fopen("2016-06-06_09-12-40_LeakageTest-FoilID_57_Long.dat","r");
   FILE *f = fopen("example.dat","r");
   Int_t i=0;

   while (!feof(f)){
      Int_t rt = fscanf(f,"%lf %lf %lf %lf %lf\n",&time_vals[i],&volt_vals[i],&volt_errs[i],&curr_vals[i],&curr_errs[i]);
       i++;
   }

   TCanvas *c1 = new TCanvas("c1","hists with different scales",600,400);

   //create/fill draw h1
   gStyle->SetOptStat(kFALSE);
   TGraphErrors * graph_volt = new TGraphErrors(n_lines,time_vals,volt_vals,nullptr,volt_errs);
   graph_volt->SetTitle("2016-06-06_09-12-40_LeakageTest-FoilID_57_Long;Time [s];Volts[V]");

   // Aesthetics of graph_volt
   graph_volt->SetMarkerStyle(1);
   graph_volt->SetMarkerColor(kBlue);
   graph_volt->SetLineColor(kBlue);
   graph_volt->Draw("APEL");
	graph_volt->SetMinimum(0);			// be sure next graph is visible
   c1->Update();
   
   TAxis * yaxis = graph_volt->GetHistogram()->GetYaxis();
   Double_t ymax = yaxis->GetXmax();
   Double_t ymin = yaxis->GetXmin();
   printf("min %f max %f\n", ymin, ymax);


   // Instance of the second graph, for the current values
   TGraphErrors * graph_curr = new TGraphErrors(n_lines,time_vals,curr_vals,nullptr,curr_errs);

   // Aesthetics of graph_curr
   graph_curr->SetMarkerStyle(1);
   graph_curr->SetMarkerColor(kRed);
   graph_curr->SetLineColor(kRed);

   //scale hint1 to the pad coordinates
//   Float_t rightmax = 1.20;

   Double_t xx, yy;
   Double_t scale = 100;
   Double_t rightmax = ymax / scale;

   for (Int_t i=0;  i<graph_curr->GetN();  i++) {
      graph_curr->GetPoint(i, xx, yy);
      printf("%f %f\n", xx, yy);
      graph_curr->SetPoint(i, xx, yy*scale);
      xx = graph_curr->GetErrorX(i);
      yy = graph_curr->GetErrorY(i);
      graph_curr->SetPointError(i, xx, yy*scale);
   }

   graph_curr->Draw("PLE");

   //draw an axis on the right side
   TGaxis *axis = new TGaxis(gPad->GetUxmax(),gPad->GetUymin(),
         gPad->GetUxmax(), gPad->GetUymax(),0,rightmax,510,"+L");
   axis->SetLineColor(kRed);
   axis->SetLabelColor(kRed);
   axis->Draw();
   c1->SetGridx();
   c1->SetGridy();
   c1->Modified();
   c1->Update();
}