j0,  j0f,  j0l,  j1,  j1f,  j1l, jn, jnf, jnl - Bessel functions of the
   first kind


   #include <math.h>

   double j0(double x);
   double j1(double x);
   double jn(int n, double x);

   float j0f(float x);
   float j1f(float x);
   float jnf(int n, float x);

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

   Link with -lm.

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

   j0(), j1(), jn():
           || /* Since glibc 2.19: */ _DEFAULT_SOURCE
           || /* Glibc versions <= 2.19: */ _SVID_SOURCE || _BSD_SOURCE
   j0f(), j0l(), j1f(), j1l(), jnf(), jnl():
       _XOPEN_SOURCE  >= 600
           || (_ISOC99_SOURCE && _XOPEN_SOURCE)
           || /* Since glibc 2.19: */ _DEFAULT_SOURCE
           || /* Glibc versions <= 2.19: */ _SVID_SOURCE || _BSD_SOURCE


   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 j0f(), j1f(), and jnf(),  functions  are  versions  that  take  and
   return  float  values.   The  j0l(),  j1l(),  and  jnl()  functions are
   versions that take and return long double values.


   On success, these functions return the appropriate Bessel value of  the
   first kind for x.

   If x is a NaN, a NaN is returned.

   If x is too large in magnitude, or the result underflows, a range error
   occurs, and the return value is 0.


   See math_error(7) for information on how to determine whether an  error
   has occurred when calling these functions.

   The following errors can occur:

   Range error: result underflow, or x is too large in magnitude
          errno is set to ERANGE.

   These functions do not raise exceptions for fetestexcept(3).


   For   an   explanation   of   the  terms  used  in  this  section,  see

   │InterfaceAttributeValue   │
   │j0(), j0f(), j0l() │ Thread safety │ MT-Safe │
   │j1(), j1f(), j1l() │ Thread safety │ MT-Safe │
   │jn(), jnf(), jnl() │ Thread safety │ MT-Safe │


   The functions returning double conform to SVr4,  4.3BSD,  POSIX.1-2001,
   and POSIX.1-2008.  The others are nonstandard functions that also exist
   on the BSDs.


   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.




   This  page  is  part of release 4.09 of the Linux man-pages project.  A
   description of the project, information about reporting bugs,  and  the
   latest     version     of     this    page,    can    be    found    at

                              2016-03-15                             J0(3)


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