module m_gsl_sf_erf
  implicit none
  
  interface
     
     ! Complementary Error Function
     ! erfc(x) := 2/Sqrt[Pi] Integrate[Exp[-t^2], {t,x,Infinity}]
     !
     ! exceptions: none
     integer function gsl_sf_erfc_e (x, result)
       use m_gsl_sf_result
       implicit none
       double precision    x
       type(gsl_sf_result) result
     end function gsl_sf_erfc_e
     
     double precision function gsl_sf_erfc (x)
       implicit none
       double precision x
     end function gsl_sf_erfc
     
     
     ! Log Complementary Error Function
     !
     ! exceptions: none
     integer function gsl_sf_log_erfc_e (x, result)
       use m_gsl_sf_result
       implicit none
       double precision    x
       type(gsl_sf_result) result
     end function gsl_sf_log_erfc_e
     
     double precision function gsl_sf_log_erfc (x)
       implicit none
       double precision x
     end function gsl_sf_log_erfc
     
     
     ! Error Function
     ! erf(x) := 2/Sqrt[Pi] Integrate[Exp[-t^2], {t,0,x}]
     !
     ! exceptions: none
     integer function gsl_sf_erf_e (x, result)
       use m_gsl_sf_result
       implicit none
       double precision    x
       type(gsl_sf_result) result
     end function gsl_sf_erf_e
     
     double precision function gsl_sf_erf (x)
       implicit none
       double precision x
     end function gsl_sf_erf
     
     
     ! Probability functions:
     ! Z(x) :  Abramowitz+Stegun 26.2.1
     ! Q(x) :  Abramowitz+Stegun 26.2.3
     !
     ! exceptions: none
     integer function gsl_sf_erf_Z_e (x, result)
       use m_gsl_sf_result
       implicit none
       double precision    x
       type(gsl_sf_result) result
     end function gsl_sf_erf_Z_e
     
     integer function gsl_sf_erf_Q_e (x, result)
       use m_gsl_sf_result
       implicit none
       double precision    x
       type(gsl_sf_result) result
     end function gsl_sf_erf_Q_e
     
     double precision function gsl_sf_erf_Z (x)
       implicit none
       double precision x
     end function gsl_sf_erf_Z
     
     double precision function gsl_sf_erf_Q (x)
       implicit none
       double precision x
     end function gsl_sf_erf_Q
     
     
#if 0
     /* Does not exist in older versions of GSL*/
     
     ! Hazard function, also known as the inverse Mill's ratio.
     !
     !   H(x) := Z(x)/Q(x)
     !         = Sqrt[2/Pi] Exp[-x^2 / 2] / Erfc[x/Sqrt[2]]
     !
     ! exceptions: GSL_EUNDRFLW
     integer function gsl_sf_hazard_e (x, result)
       use m_gsl_sf_result
       implicit none
       double precision    x
       type(gsl_sf_result) result
     end function gsl_sf_hazard_e
     
     double precision function gsl_sf_hazard (x)
       implicit none
       double precision x
     end function gsl_sf_hazard
#endif
     
  end interface
  
end module m_gsl_sf_erf