## Bessel Functions

The routines described in this section compute the Cylindrical Bessel functions J_n(x), Y_n(x), Modified cylindrical Bessel functions I_n(x), K_n(x), Spherical Bessel functions j_l(x), y_l(x), and Modified Spherical Bessel functions i_l(x), k_l(x). For more information see Abramowitz & Stegun, Chapters 9 and 10. The Bessel functions are defined in the header file ``gsl_sf_bessel.h'`.

- Regular Cylindrical Bessel Functions
- Irregular Cylindrical Bessel Functions
- Regular Modified Cylindrical Bessel Functions
- Irregular Modified Cylindrical Bessel Functions
- Regular Spherical Bessel Functions
- Irregular Spherical Bessel Functions
- Regular Modified Spherical Bessel Functions
- Irregular Modified Spherical Bessel Functions
- Regular Bessel Function - Fractional Order
- Irregular Bessel Functions - Fractional Order
- Regular Modified Bessel Functions - Fractional Order
- Irregular Modified Bessel Functions - Fractional Order
- Zeros of Regular Bessel Functions