tabulation.h

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#ifndef AIMS_FASTCOMPUTATION_TABULATION_H
#define AIMS_FASTCOMPUTATION_TABULATION_H
 
#include <math.h>
#include <vector>
#include <aims/def/general.h>
 
namespace aims {
 
class RealToRealFunctionTabulation
{
public:
 
  typedef double (*function_type)( const double & );
 
  RealToRealFunctionTabulation( const function_type function,
                                const double &min,
                                const double &max,
                                const ulong tableSize );
 
  ulong getIndex( const double & ) const;
  const double &operator ()( const double & ) const;
  const double &operator []( ulong ) const;
 
protected:
 
  double _minimum, _sampling;
  std::vector<double> _table;
};
 
 
inline const double &
RealToRealFunctionTabulation::operator []( ulong i ) const
{
  return _table[ i ];
}
 
inline ulong RealToRealFunctionTabulation::getIndex( const double &v ) const
{
  return ulong( rint( ( v - _minimum ) / _sampling ) );
}
 
 
inline const double &
RealToRealFunctionTabulation::operator ()( const double &v ) const
{
  return _table[ getIndex( v ) ];
}
 
} // namespace aims
 
 
#endif