'\" te
.\" Copyright 1989 AT&T.  Copyright (c) 2004, Sun Microsystems, Inc.  All Rights Reserved.
.\" The contents of this file are subject to the terms of the Common Development and Distribution License (the "License").  You may not use this file except in compliance with the License.
.\" You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing.  See the License for the specific language governing permissions and limitations under the License.
.\" When distributing Covered Code, include this CDDL HEADER in each file and include the License file at usr/src/OPENSOLARIS.LICENSE.  If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner]
.TH isnand 3C "15 Jun 2004" "SunOS 5.11" "Standard C Library Functions"
.SH NAME
isnand, isnanf, finite, fpclass, unordered \- determine type of floating-point
number
.SH SYNOPSIS
.LP
.nf
#include <ieeefp.h>

\fBint\fR \fBisnand\fR(\fBdouble\fR \fIdsrc\fR);
.fi

.LP
.nf
\fBint\fR \fBisnanf\fR(\fBfloat\fR \fIfsrc\fR);
.fi

.LP
.nf
\fBint\fR \fBfinite\fR(\fBdouble\fR \fIdsrc\fR);
.fi

.LP
.nf
\fBfpclass_t\fR \fBfpclass\fR(\fBdouble\fR \fIdsrc\fR);
.fi

.LP
.nf
\fBint\fR \fBunordered\fR(\fBdouble\fR \fIdsrc1\fR, \fBdouble\fR \fIdsrc2\fR);
.fi

.SH DESCRIPTION
.sp
.LP
The \fBisnand()\fR and \fBisnanf()\fR functions return \fBTRUE\fR (\fB1\fR) if
the argument \fIdsrc\fR or \fIfsrc\fR is a NaN;  otherwise they return
\fBFALSE\fR (\fB0\fR).
.sp
.LP
The \fBfpclass()\fR function returns one of the following classes to which
\fIdsrc\fR belongs:
.sp
.ne 2
.mk
.na
\fB\fBFP_SNAN\fR\fR
.ad
.RS 14n
.rt  
signaling NaN
.RE

.sp
.ne 2
.mk
.na
\fB\fBFP_QNAN\fR\fR
.ad
.RS 14n
.rt  
quiet NaN
.RE

.sp
.ne 2
.mk
.na
\fB\fBFP_NINF\fR\fR
.ad
.RS 14n
.rt  
negative infinity
.RE

.sp
.ne 2
.mk
.na
\fB\fBFP_PINF\fR\fR
.ad
.RS 14n
.rt  
positive infinity
.RE

.sp
.ne 2
.mk
.na
\fB\fBFP_NDENORM\fR\fR
.ad
.RS 14n
.rt  
negative denormalized non-zero
.RE

.sp
.ne 2
.mk
.na
\fB\fBFP_PDENORM\fR\fR
.ad
.RS 14n
.rt  
positive denormalized non-zero
.RE

.sp
.ne 2
.mk
.na
\fB\fBFP_NZERO\fR\fR
.ad
.RS 14n
.rt  
negative zero
.RE

.sp
.ne 2
.mk
.na
\fB\fBFP_PZERO\fR\fR
.ad
.RS 14n
.rt  
positive zero
.RE

.sp
.ne 2
.mk
.na
\fB\fBFP_NNORM\fR\fR
.ad
.RS 14n
.rt  
negative normalized non-zero
.RE

.sp
.ne 2
.mk
.na
\fB\fBFP_PNORM\fR\fR
.ad
.RS 14n
.rt  
positive normalized non-zero
.RE

.sp
.LP
The \fBfinite()\fR function returns \fBTRUE\fR (\fB1\fR) if the argument
\fIdsrc\fR is neither infinity nor NaN; otherwise it returns  \fBFALSE\fR
(\fB0\fR).
.sp
.LP
The \fBunordered()\fR function returns \fBTRUE\fR (\fB1\fR) if one of its two
arguments is unordered with respect to the other argument.  This is equivalent
to reporting whether either argument is NaN.  If neither argument is NaN,
\fBFALSE\fR (\fB0\fR) is returned.
.sp
.LP
None of these functions generates an exception, even for signaling NaNs.
.SH RETURN VALUES
.sp
.LP
See DESCRIPTION.
.SH ATTRIBUTES
.sp
.LP
See \fBattributes\fR(5) for descriptions of the following attributes:
.sp

.sp
.TS
tab() box;
cw(2.75i) |cw(2.75i) 
lw(2.75i) |lw(2.75i) 
.
ATTRIBUTE TYPEATTRIBUTE VALUE
_
MT-LevelMT-Safe
.TE

.SH SEE ALSO
.sp
.LP
\fBfpgetround\fR(3C), \fBisnan\fR(3M), \fBattributes\fR(5)