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     BESSEL(3M)                                             BESSEL(3M)

     NAME
          besj0, besj1, besjn, besy0, besy1, besyn - bessel functions

     SYNOPSIS
          #include <math.h>

          double besj0(x)
          double x;

          double besj1(x)
          double x;

          double besjn(n, x)
          double x;

          double besy0(x)
          double x;

          double besy1(x)
          double x;

          double besyn(n, x)
          double x;

     DESCRIPTION
          These functions calculate Bessel functions of the first and
          second kinds for real arguments and integer orders.

     DIAGNOSTICS
          Negative arguments cause besy0, besy1, and besyn to return a
          huge negative value and set errno to EDOM.