jn

function

Library: Bessel functions (OMBESSEL)
Import : ombessel.xmd

Returns: a Bessel function of the first kind: order n

Declaration

define external float function
     jn (value integer n, value float x)

Purpose

Use jn to calculate the Bessel function of the first kind (order n) for any value of x.

Example:

  import "ombessel.xmd" unprefixed
  import "omfloat.xmd" unprefixed
  process
     local integer x initial {2}
     local float y initial {17.5}   
     local float jn-bessel
     set jn-bessel to jn (x, y)
     output "A jn Bessel function of the first kind, order "
         || "d" % x
         || ", of "
         || "d" % y
         || " = "
         || "d" % jn-bessel
         || "%n"
  ; Output: "A jn Bessel function of the first kind, order 2, of 17.5 = 0.084433830294314"

Other Library Functions