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.TH FMOD 3M "Jul 12, 2006" "SunOS 5.11" "Mathematical Library Functions"
.SH NAME
fmod, fmodf, fmodl \- floating-point remainder value function
.SH SYNOPSIS
.LP
.nf
c99 [ \fIflag\fR... ] \fIfile\fR... \fB-lm\fR [ \fIlibrary\fR... ]
#include <math.h>

\fBdouble\fR \fBfmod\fR(\fBdouble\fR \fIx\fR, \fBdouble\fR \fIy\fR);
.fi

.LP
.nf
\fBfloat\fR \fBfmodf\fR(\fBfloat\fR \fIx\fR, \fBfloat\fR \fIy\fR);
.fi

.LP
.nf
\fBlong double\fR \fBfmodl\fR(\fBlong double\fR \fIx\fR, \fBlong double\fR \fIy\fR);
.fi

.SH DESCRIPTION
.sp
.LP
These functions return the floating-point remainder of the division of \fIx\fR
by \fIy\fR.
.SH RETURN VALUES
.sp
.LP
These functions return the value \fIx\fR \(mi \fIi\fR * \fIy\fR, for some
integer \fIi\fR such that, if \fIy\fR is non-zero, the result has the same sign
as \fIx\fR and magnitude less than the magnitude of \fIy\fR.
.sp
.LP
If \fIx\fR or \fIy\fR is NaN, a NaN is returned.
.sp
.LP
If \fIy\fR is 0, a domain error occurs and a NaN is returned.
.sp
.LP
If \fIx\fR is infinite, a domain error occurs and a NaN is returned.
.sp
.LP
If \fIx\fR is \(+-0 and \fIy\fR is not 0, \(+-0 is returned.
.sp
.LP
If \fIx\fR is not infinite and \fIy\fR is \(+-Inf, \fIx\fR is returned.
.SH ERRORS
.sp
.LP
These functions will fail if:
.sp
.ne 2
.mk
.na
\fBDomain Error\fR
.ad
.RS 16n
.rt
The \fIx\fR argument is infinite or \fIy\fR is 0.
.sp
If the integer expression (\fBmath_errhandling\fR & \fBMATH_ERREXCEPT\fR) is
non-zero, the invalid floating-point exception is raised.
.RE

.SH USAGE
.sp
.LP
An application wanting to check for exceptions should call
\fBfeclearexcept\fR(\fBFE_ALL_EXCEPT\fR) before calling these functions. On
return, if \fBfetestexcept\fR(\fBFE_INVALID\fR | \fBFE_DIVBYZERO\fR |
\fBFE_OVERFLOW\fR | \fBFE_UNDERFLOW\fR) is non-zero, an exception has been
raised. An application should either examine the return value or check the
floating point exception flags to detect exceptions.
.SH ATTRIBUTES
.sp
.LP
See \fBattributes\fR(7) for descriptions of the following attributes:
.sp

.sp
.TS
tab(	) box;
cw(2.75i) |cw(2.75i)
lw(2.75i) |lw(2.75i)
.
ATTRIBUTE TYPE	ATTRIBUTE VALUE
_
Interface Stability	Standard
_
MT-Level	MT-Safe
.TE

.SH SEE ALSO
.sp
.LP
.BR math.h (3HEAD),
.BR feclearexcept (3M),
.BR fetestexcept (3M),
.BR isnan (3M),
.BR attributes (7),
.BR standards (7)