double remainder(doublex, doubley);
float remainderf(floatx, floaty);
long double remainderl(long doublex, long doubley);

DESCRIPTION

These functions shall return the floating-point remainder r=
x- ny when y is non-zero. The value
n is the integral value nearest the exact value x/ y.
When |n-x/y|=0.5, the value
n is chosen to be even.

The behavior of remainder() shall be independent of the rounding
mode.

RETURN VALUE

Upon successful completion, these functions shall return the floating-point
remainder r= x- ny when
y is non-zero.

If
x or y is NaN, a NaN shall be returned.

If x is infinite or y is 0 and the other is non-NaN, a
domain error shall occur, and either a NaN (if supported),
or an implementation-defined value shall be returned.

ERRORS

These functions shall fail if:

Domain Error

The x argument is ±Inf, or the y argument is ±0
and the other argument is non-NaN.

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.

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

abs() , div() , feclearexcept() , fetestexcept()
, ldiv() , the Base Definitions volume of IEEE Std 1003.1-2001,
Section 4.18, Treatment of Error Conditions 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 Technology
-- 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 .