bessel functions (3f)

returns Bessel functions of two kinds for orders 0 and 1

Syntax

  real*4 besj0, bessl, x
  external besj0
  bessl = besj0 ( x )

  real*4 besj1, bessl, x
  external besj1
  bessl = besj1 ( x )

  real*4 besjn, bessl, x
  integer*4 n
  external besjn
  bessl = besjn ( n, x )

  real*4 besy0, bessl, x
  external besy0
  bessl = besy0 ( x )

  real*4 besy1, bessl, x
  external besy1
  bessl = besy1 ( x )

  real*4 besyn, bessl, x
  integer*4 n
  external besyn
  bessl = besyn ( n, x )

  real*8 dbesj0, dbessl, x
  external dbesj0
  dbessl = dbesj0 ( x )

  real*8 dbesj1, dbessl, x
  external dbesj1
  dbessl = dbesj1 ( x )

  real*8 dbesjn, dbessl, x
  integer*4 n
  external dbesjn
  dbessl = dbesjn ( n, x )

  real*8 dbesy0, dbessl, x
  external dbesy0
  dbessl = dbesy0 ( x )

  real*8 dbesy1, dbessl, x
  external dbesy1
  dbessl = dbesy1 ( x )

  real*8 dbesyn, dbessl, x
  integer*4 n
  external dbesyn
  dbessl = dbesyn ( n, x )

Description

  The functions ending in j0 and j1 return Bessel functions of x of the first
  kind of orders 0 and 1, respectively.  The functions ending in jn return
  the Bessel function of x of the first kind of order n .

  The functions ending in y0 and y1 return Bessel functions of x of the
  second kind of orders 0 and 1, respectively.  The functions ending in yn
  return the Bessel function of x of the second kind of order n . The value
  of x must be positive.

Diagnostics

  A negative argument causes functions ending in y0, y1, and yn to return a
  quiet NaN.

Restrictions

  An argument that is too large in magnitude causes functions ending in j0,
  j1, y0, and y1 to return zero without an indication of the total loss of
  precision.

See Also

  perror(3f), j0(3m)