centos man page for y0

Y0(3P)							     POSIX Programmer's Manual							    Y0(3P)

PROLOG
       This  manual page is part of the POSIX Programmer's Manual.  The Linux implementation of this interface may differ (consult the correspond-
       ing Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

NAME
       y0, y1, yn - Bessel functions of the second kind

SYNOPSIS
       #include <math.h>

       double y0(double x);
       double y1(double x);
       double yn(int n, double x);

DESCRIPTION
       The y0(), y1(), and yn() functions shall compute Bessel functions of x of the second kind of orders 0, 1, and n, respectively.

       An application wishing to check for error situations should set errno to zero and call feclearexcept(FE_ALL_EXCEPT)  before  calling  these
       functions.   On	return, if errno is non-zero or fetestexcept(FE_INVALID | FE_DIVBYZERO | FE_OVERFLOW | FE_UNDERFLOW) is non-zero, an error
       has occurred.

RETURN VALUE
       Upon successful completion, these functions shall return the relevant Bessel value of x of the second kind.

       If x is NaN, NaN shall be returned.

       If the x argument to these functions is negative, -HUGE_VAL or NaN shall be returned, and a domain error may occur.

       If x is 0.0, -HUGE_VAL shall be returned and a range error may occur.

       If the correct result would cause underflow, 0.0 shall be returned and a range error may occur.

       If the correct result would cause overflow, -HUGE_VAL or 0.0 shall be returned and a range error may occur.

ERRORS
       These functions may fail if:

       Domain Error
	      The value of x is negative.

       If the integer expression (math_errhandling & MATH_ERRNO) is non-zero, then errno shall	be  set  to  [EDOM].  If  the  integer	expression
       (math_errhandling & MATH_ERREXCEPT) is non-zero, then the invalid floating-point exception shall be raised.

       Range Error
	      The value of x is 0.0, or the correct result would cause overflow.

       If  the	integer  expression  (math_errhandling	&  MATH_ERRNO) is non-zero, then errno shall be set to [ERANGE]. If the integer expression
       (math_errhandling & MATH_ERREXCEPT) is non-zero, then the overflow floating-point exception shall be raised.

       Range Error
	      The value of x is too large in magnitude, or the correct result would cause underflow.

       If the integer expression (math_errhandling & MATH_ERRNO) is non-zero, then errno shall be set  to  [ERANGE].  If  the  integer	expression
       (math_errhandling & MATH_ERREXCEPT) is non-zero, then the underflow floating-point exception shall be raised.

       The following sections are informative.

EXAMPLES
       None.

APPLICATION USAGE
       On  error,  the	expressions  (math_errhandling & MATH_ERRNO) and (math_errhandling & MATH_ERREXCEPT) are independent of each other, but at
       least one of them must be non-zero.

RATIONALE
       None.

FUTURE DIRECTIONS
       None.

SEE ALSO
       feclearexcept(), fetestexcept(), isnan(), j0(), the Base Definitions volume of IEEE Std 1003.1-2001, Section 4.18, Treatment of Error  Con-
       ditions for Mathematical Functions, <math.h>

COPYRIGHT
       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technol-
       ogy -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of
       Electrical  and	Electronics  Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE
       and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can  be  obtained
       online at http://www.opengroup.org/unix/online.html .

IEEE
/The Open Group						       2003								    Y0(3P)