Irregular Modified Bessel Functions - Fractional Order

Function: double gsl_sf_bessel_Knu (double nu, double x)
Function: int gsl_sf_bessel_Knu_e (double nu, double x, gsl_sf_result * result)
These routines compute the irregular modified Bessel function of fractional order nu, K_\nu(x) for x>0, \nu>0.

Function: double gsl_sf_bessel_lnKnu (double nu, double x)
Function: int gsl_sf_bessel_lnKnu_e (double nu, double x, gsl_sf_result * result)
These routines compute the logarithm of the irregular modified Bessel function of fractional order nu, \ln(K_\nu(x)) for x>0, \nu>0.

Function: double gsl_sf_bessel_Knu_scaled (double nu, double x)
Function: int gsl_sf_bessel_Knu_scaled_e (double nu, double x, gsl_sf_result * result)
These routines compute the scaled irregular modified Bessel function of fractional order nu, \exp(+|x|) K_\nu(x) for x>0, \nu>0.