REMAINDER(P) POSIX Programmer's Manual REMAINDER(P)
remainder, remainderf, remainderl - remainder function
double remainder(double x, double y);
float remainderf(float x, float y);
long double remainderl(long double x, long double y);
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.
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.
These functions shall fail if:
The x argument is +-Inf, or the y argument is +-0 and the other argument is non-
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.
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.
abs() , div() , feclearexcept() , fetestexcept() , ldiv() , the Base Definitions volume of
IEEE Std 1003.1-2001, Section 4.18, Treatment of Error Conditions for Mathematical Func-
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 orig-
inal Standard can be obtained online at http://www.opengroup.org/unix/online.html .
IEEE/The Open Group 2003 REMAINDER(P)