bessel(3M)                     DG/UX 5.4R3.00                     bessel(3M)


NAME
       bessel: j0, j1, jn, y0, y1, yn - Bessel functions

SYNOPSIS
       cc [flag ...] file ...  -lm [library ...]

       #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);

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

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

   Considerations for Threads Programming
                     +---------+-----------------------------+
                     |         |                      async- |
                     |function | reentrant   cancel   cancel |
                     |         |              point    safe  |
                     +---------+-----------------------------+
                     |j0       |     Y          N        N   |
                     |j1       |     Y          N        N   |
                     |jn       |     Y          N        N   |
                     |y0       |     Y          N        N   |
                     |y1       |     Y          N        N   |
                     |yn       |     Y          N        N   |
                     +---------+-----------------------------+
DIAGNOSTICS
       Non-positive arguments cause y0, y1, and yn to return the value -HUGE
       and to set errno to EDOM.  In addition, a message indicating DOMAIN
       error is printed on the standard error output.

       Arguments too large in magnitude cause j0, j1, y0, and y1 to return 0
       and to set errno to ERANGE.  In addition, a message indicating TLOSS
       error is printed on the standard error output.

       Except when the -Xc compilation option is used, these error-handling
       procedures may be changed with the function matherr.  When the -Xa or
       -Xc compilation options are used, HUGEVAL is returned instead of



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bessel(3M)                     DG/UX 5.4R3.00                     bessel(3M)


       HUGE and no error messages are printed.

SEE ALSO
       reentrant(3), matherr(3M).





















































Licensed material--property of copyright holder(s)                         2