J0(3)			   Linux Programmers Manual			J0(3)



NAME
       j0,  j0f,  j0l, j1, j1f, j1l, jn, jnf, jnl, y0, y0f, y0l, y1, y1f, y1l,
       yn, ynf, ynl - Bessel functions

SYNOPSIS
       #include 

       double j0(double x);
       double j1(double x);
       double jn(int n, double x);
       double y0(double x);
       double y1(double x);
       double yn(int n, double x);

       float j0f(float x);
       float j1f(float x);
       float jnf(int n, float x);
       float y0f(float x);
       float y1f(float x);
       float ynf(int n, float x);

       long double j0l(long double x);
       long double j1l(long double x);
       long double jnl(int n, long double x);
       long double y0l(long double x);
       long double y1l(long double x);
       long double ynl(int n, long double x);

       Link with -lm.

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       For all of these functions: _SVID_SOURCE || _BSD_SOURCE ||
       _XOPEN_SOURCE

DESCRIPTION
       The  j0()  and j1() functions return Bessel functions of x of the first
       kind of orders 0 and 1, respectively.  The jn()	function  returns  the
       Bessel function of x of the first kind of order n.

       The  y0() and y1() functions return Bessel functions of x of the second
       kind of orders 0 and 1, respectively.  The yn()	function  returns  the
       Bessel function of x of the second kind of order n.

       For the functions y0(), y1() and yn(), the value of x must be positive.
       For negative values of x, these functions return -HUGE_VAL.

       The j0f() etc. and j0l() etc. functions	are  versions  that  take  and
       return float and long double values, respectively.

CONFORMING TO
       The functions returning double conform to SVr4, 4.3BSD, POSIX.1-2001.

BUGS
       There  are  errors  of up to 2e-16 in the values returned by j0(), j1()
       and jn() for values of x between -8 and 8.

COLOPHON
       This page is part of release 3.05 of the Linux  man-pages  project.   A
       description  of	the project, and information about reporting bugs, can
       be found at http://www.kernel.org/doc/man-pages/.



				  2007-07-26				 J0(3)