source: trunk/c++_tools/statistics/Histogram.cc @ 675

// $Id: Histogram.cc 675 2006-10-10 12:08:45Z jari $

/*
  Copyright (C) The authors contributing to this file.

  This file is part of the yat library, http://lev.thep.lu.se/trac/yat

  The yat library is free software; you can redistribute it and/or
  modify it under the terms of the GNU General Public License as
  published by the Free Software Foundation; either version 2 of the
  License, or (at your option) any later version.

  The yat library is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program; if not, write to the Free Software
  Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
  02111-1307, USA.
*/

#include "yat/statistics/Histogram.h"

#include <cmath>
#include <fstream>


namespace theplu {
namespace statistics {


Histogram::Histogram(void)
  : xmax_(0), xmin_(0), sum_all_(), sum_histogram_()
{
}



Histogram::Histogram(const Histogram& b)
{
  *this=b;
}



Histogram::Histogram(const double min, const double max, const size_t n)
  : histogram_(std::vector<double>(n,0.0)),
    xmax_(max), xmin_(min),
    sum_all_(), sum_histogram_()
{
}



Histogram::~Histogram(void)
{
}



int Histogram::add(const double x, const double w)
{
  sum_all_.add(x,w);
  if (x<xmin_)
    return -1;
  else if (x>=xmax_)
    return 1;
  
  sum_histogram_.add(x,w);
  histogram_[bin(x)] += w;
  return 0;
}



void Histogram::normalize(bool choice)
{
  double scale_factor;
  if (choice) 
    scale_factor = sum_all_.sum_w();
  else
    scale_factor = sum_all_.sum_w()*spacing();
  for (size_t i=0; i<histogram_.size(); i++)
    histogram_[i]/=scale_factor;

}


void Histogram::reset(void)
{
  for (u_int i=0; i<histogram_.size(); i++)
    histogram_[i]=0;
  sum_all_.reset();
  sum_histogram_.reset();
}



const Histogram& Histogram::operator=(const Histogram& b)
{
  if (this==&b)
    return *this;
  histogram_=b.histogram_;
  xmax_=b.xmax_;
  xmin_=b.xmin_;
  sum_all_=b.sum_all_;
  sum_histogram_=b.sum_histogram_;
  return *this;
}



std::ostream& operator<<(std::ostream& s,const Histogram& histogram)
{
  s << "# histogram min : " << histogram.xmin() << '\n';
  s << "# histogram max : " << histogram.xmax() << '\n';
  s << "# number of bins: " << histogram.nof_bins() << '\n';
  s << "# nof points in histogram : " 
    << histogram.averager_histogram().sum_w() << '\n';
  s << "# nof points in total:      " 
    << histogram.averager_all().sum_w() << '\n';
  s << "# column 1: center of observation bin\n"
    << "# column 2: frequency\n";

  for (u_int i=0; i<histogram.nof_bins(); i++) {
    s.width(12);
    s << histogram.observation_value(i);
    s.width(12);
    s << histogram[i] << '\n';
  }

  return s;
}

}} // of namespace statistics and namespace theplu