//--------------------------------------------------------------------------
// File and Version Information:
//      $Id: specrespvector.cc,v 1.3 1999-11-21 23:25:47 ansari Exp $
//
// Description:
//      Aim of the class: To give the energy density
//                        The unity used here is W/m^2/Hz/sr
//
// History (add to end):
//      Sophie   Oct, 1999  - creation
//
//------------------------------------------------------------------------

//---------------
// C++ Headers --
//---------------
#include "machdefs.h"
#include <iostream.h>
#include <math.h>
// #include <typeinfo>

#include "specrespvector.h"
#include "pexceptions.h"

//----------------
// Constructor --
//----------------
SpecRespVec::SpecRespVec(Vector const & nu, Vector const & fdenu, double numin, double numax)
        : SpectralResponse(numin, numax)
{
  if(nu.NElts() != fdenu.NElts())  
    throw SzMismatchError("SpecRespVec::SpecRespVec() - Non equal vector sizes");
  _vecOfNu = nu;
  _vecOfFDeNu = fdenu;
  _numin = nu(0);
  _numax = nu(nu.NElts()-1);
  if(_vecOfNu.NElts() != _vecOfFDeNu.NElts()) cout << "vectors are not compatible" << exit;
}


//--------------
// Destructor --
//--------------
SpecRespVec::~SpecRespVec()
{
}

//              ---------------------------
//              --  Function Definitions --
//              ---------------------------



 
double 
SpecRespVec::transmission(double nu)  const 
{
  if ( (nu < _numin) || (nu > _numax) ) return(0.);
  double value = 0.;
  int sizeVecOfNu = _vecOfNu.NElts();
  if(nu <=  _vecOfNu(0)) return _vecOfFDeNu(0);
  if(nu >=  _vecOfNu(sizeVecOfNu-1)) return _vecOfFDeNu(sizeVecOfNu-1);

  for (int i=1; i<sizeVecOfNu; i++)
    {
      if(nu < _vecOfNu(i))
	{
	  double up = _vecOfFDeNu(i) ;
	  double down = _vecOfFDeNu(i-1);
	  double xmin = _vecOfNu(i-1);
	  double xmax = _vecOfNu(i);
	  double a = ((up-down)/(xmax-xmin));
	  value = a*nu+(up-a*xmax);
	  return value;
	}
    }
  return value;
}



void
SpecRespVec::Print(ostream& os) const 
{

  //   os << "SpecRespVec::Print (" << typeid(*this).name() 
  //<< ") - Fmin,Fmax= " << minFreq() << "," << maxFreq() << endl;
  os << "SpecRespVec ::Print - Fmin,Fmax= " << minFreq() << "," << maxFreq() << endl;
  os << "MeanFreq= " << meanFreq() << "  Transmission= " << transmission(meanFreq()) << endl;
  os << "PeakFreq= " << peakFreq() << "  Transmission= " << transmission(peakFreq()) << endl;

}