/home/marsyas/marsyas/src/marsyas/Kurtosis.cpp

/*
** Copyright (C) 1998-2006 George Tzanetakis <gtzan@cs.uvic.ca>
**  
** This program 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.
** 
** This program 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 "Kurtosis.h"

using std::ostringstream;
using namespace Marsyas;


Kurtosis::Kurtosis(mrs_string name):MarSystem("Kurtosis",name)
{
  z_ = 0.0;
  b_ = 0.0;
  q_ = 0.0;
}


Kurtosis::~Kurtosis()
{
}


MarSystem* 
Kurtosis::clone() const 
{
  return new Kurtosis(*this);
}

void
Kurtosis::myUpdate(MarControlPtr sender)
{
    (void) sender;
  MRSDIAG("Kurtosis.cpp - Kurtosis:myUpdate");
  
  setctrl("mrs_natural/onSamples", getctrl("mrs_natural/inSamples"));
  setctrl("mrs_natural/onObservations", (mrs_natural)1);
  setctrl("mrs_real/osrate", getctrl("mrs_real/israte"));
  setctrl("mrs_string/onObsNames", "Kurtosis,");

  //defaultUpdate(); [!]
    inObservations_ = getctrl("mrs_natural/inObservations")->to<mrs_natural>();

    obsrow_.create(inObservations_);
}


void 
Kurtosis::myProcess(realvec& in, realvec& out)
{
    mrs_natural o,t;
  //checkFlow(in,out);

    // old code for Kurtosis calculation 
    
/*  for (t = 0; t < inSamples_; t++)
    {
        
        for (o=0; o < inObservations_; o++)
        {
            obsrow_(o) = in(o,t);
        }
        z_ = 0.0;
        mrs_real mean = obsrow_.mean();
        for (o=0; o < inObservations_; o++)
        {
            b_ =  obsrow_(o) - mean ;
            
            // take x - u to the fourth power into the sum
            z_ += (b_ * b_ * b_ * b_); 
        }
        
        // standard deviation to the fourth power
        q_ = obsrow_.var() * obsrow_.var();
        
        
        if ((z_ < 1.0e-45)||(q_ < 1.0e-45))
            out(0,t) = 0.5;
        else 
        {
        // out(0,t) = (mrs_real)((z_ /  q_ * inObservations_) - 3.0);
            out(0,t) = (mrs_real)((z_ /  q_ ) - 3.0);
        }
    }   
    

    cout << "k1 = " << out(0,0) << endl;
*/  
    
    
    for (t = 0; t < inSamples_; t++)
    {
        
        for (o=0; o < inObservations_; o++)
        {
            obsrow_(o) = in(o,t);
        }
        z_ = 0.0;
        mrs_real mean = obsrow_.mean();
        for (o=0; o < inObservations_; o++)
        {
            obsrow_(o) =  obsrow_(o) - mean ;
            b_ = obsrow_(o);
            
            z_ += (b_ * b_ * b_ * b_); 
            q_  += (b_ * b_);
        }
        q_ = q_ * q_;
        q_ = q_ / inObservations_;
        
        if ((z_ < 1.0e-45)||(q_ < 1.0e-45))
            out(0,t) = 0.5;
        else 
        {
            out(0,t) = (mrs_real)((z_ /  q_ ) - 3.0);
        }
    }   


//  cout << "k2 = " << out(0,0) << endl;
}

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