J0(3)              Linux Programmer's 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 <math.h>

       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);

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 func-
       tions 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  SVID  3,  BSD
       4.3,  XPG4,  POSIX  1003.1-2001. The other functions are
       C99 requirements.

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.



                           2002-08-25                     J0(3)
