DEFINITION MODULE BessMod;

 (* EXPORT QUALIFIED BessI0, BessK0, BessI1, BessK1, BessI, BessK; *)

   PROCEDURE BessI0(x: REAL): REAL; 
   (*
     Returns the modified Bessel function I0(x) for any real x.
   *)

   PROCEDURE BessK0(x: REAL): REAL; 
   (*
     Returns the modified Bessel function K0(x) for positive real x.
   *)

   PROCEDURE BessI1(x: REAL): REAL; 
   (*
     Returns the modified Bessel function I1(x) for any real x.
   *)

   PROCEDURE BessK1(x: REAL): REAL; 
   (*
     Returns the modified Bessel function K1(x) for positive real x.
   *)

   PROCEDURE BessI(n: INTEGER; x: REAL): REAL; 
   (*
     Returns the modified Bessel function In(x) for any real
     x and n >= 2.
   *)

   PROCEDURE BessK(n: INTEGER; x: REAL): REAL; 
   (*
     Returns the modified Bessel function Kn(x) for positive
     x and n >= 2.
   *)

END BessMod.
