MathSupplement.h

 
#ifndef IIR1_MATHSUPPLEMENT_H
#define IIR1_MATHSUPPLEMENT_H
 
#include "Common.h"
 
#include<complex>
 
#ifdef _MSC_VER
 // Under Unix these have already default instantiations but not under Vis Studio
template class IIR_EXPORT std::complex<double>;
template class IIR_EXPORT std::complex<float>;
#endif
 
namespace Iir {
 
const double doublePi   =3.1415926535897932384626433832795028841971;
const double doublePi_2 =1.5707963267948966192313216916397514420986;
const double doubleLn2  =0.69314718055994530941723212145818;
const double doubleLn10 =2.3025850929940456840179914546844;
 
typedef std::complex<double> complex_t;
typedef std::pair<complex_t, complex_t> complex_pair_t;
 
inline const complex_t infinity()
{
  return complex_t (std::numeric_limits<double>::infinity());
}
 
template <typename Ty, typename To>
inline std::complex<Ty> addmul (const std::complex<Ty>& c,
                                Ty v,
                                const std::complex<To>& c1)
{
  return std::complex <Ty> (
    c.real() + v * c1.real(), c.imag() + v * c1.imag());
}
 
template <typename Ty>
inline Ty asinh (Ty x)
{
  return log (x + std::sqrt (x * x + 1 ));
}
 
template <typename Ty>
inline bool is_nan (Ty v)
{
  return !(v == v);
}
 
template <>
inline bool is_nan<complex_t> (complex_t v)
{
  return Iir::is_nan (v.real()) || Iir::is_nan (v.imag());
}
 
}
 
#endif