/**********************************************************

This software is part of J.-S. Caux's ABACUS library.

Copyright (c) J.-S. Caux.

-----------------------------------------------------------

File:  Analyze_RAW_File.cc

Purpose:  give some statistics for the matrix element distribution in a raw file.

***********************************************************/

#include "ABACUS.h"

using namespace std;
using namespace ABACUS;


int main(int argc, char* argv[])
{
  if (argc != 4) {
    cout << "Argument needed: rawfile, iKmin, iKmax." << endl;
    ABACUSerror("");
  }

  const char* rawfilename = argv[1];
  int iKmin = atoi(argv[2]);
  int iKmax = atoi(argv[3]);

  ifstream RAW_infile;
  RAW_infile.open(rawfilename);
  if (RAW_infile.fail()) {
    cout << rawfilename << endl;
    ABACUSerror("Could not open RAW_infile... ");
  }

  DP omega;
  int iK;
  DP FF;
  DP dev;
  string label;

  DP sumFFsq = 0.0;
  DP sumFF4 = 0.0;
  DP sumFFsqlnFFsq = 0.0;

  Vect<int> nFFatK (0, iKmax - iKmin + 1);
  Vect<DP> sumFFsqatK (0.0, iKmax - iKmin + 1);
  Vect<DP> sumFF4atK (0.0, iKmax - iKmin + 1);
  Vect<DP> sumFFsqlnFFsqatK (0.0, iKmax - iKmin + 1);

  int nread = 0;

  while (RAW_infile.peek() != EOF) {
    RAW_infile >> omega >> iK >> FF >> dev >> label;

    nread++;
    sumFFsq += FF*FF;
    sumFF4 += FF*FF*FF*FF;
    sumFFsqlnFFsq += FF*FF * log(FF*FF);

    if (iK >= iKmin && iK <= iKmax) {
      nFFatK[iK-iKmin] += 1;
      sumFFsqatK[iK - iKmin] += FF*FF;
      sumFF4atK[iK - iKmin] += FF*FF*FF*FF;
      sumFFsqlnFFsqatK[iK - iKmin] += FF*FF * log(FF*FF);
    }
  }

  RAW_infile.close();

  cout << "Inverse participation ratio: \t" << sumFF4/(sumFFsq*sumFFsq) << endl;
  // Entropy is -sum (FFsq/sumFFsq) * ln(FFsq/sumFFsq) = sum (FFsq lnFFsq - FFsq ln sumFFsq)/sumFFsq
  cout << "Entropy: \t" << -(sumFFsqlnFFsq - sumFFsq * log(sumFFsq))/sumFFsq << endl;

  cout << "iK\tnFFatK\tIPRatiK\tentropyatiK:" << endl;
  for (int iK = iKmin; iK <= iKmax; ++iK)
    cout << iK << "\t" << nFFatK[iK-iKmin] << "\t"
	 << sumFF4atK[iK-iKmin]/(sumFFsqatK[iK - iKmin] * sumFFsqatK[iK - iKmin]) << "\t"
	 << -(sumFFsqlnFFsqatK[iK-iKmin] - sumFFsqatK[iK-iKmin] * log(sumFFsqatK[iK-iKmin])
	      )/sumFFsqatK[iK-iKmin]<< endl;

  return(0);
}