bessel(3M)               UNIX System V(Math Libraries)               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.

SEE ALSO
      matherr(3M).

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 HUGE and no
      error messages are printed.









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