isnand.3m

<B>Digital的Unix操作系统VAX 4.2源码</B>

.TH isnand 3m RISC
.SH Name
isnand, isnanf \- test for floating point NaN (Not-A-Number)
.SH Syntax
.B
\#include <ieeefp.h>
.PP
.B int isnand (dsrc)
.br
.B double dsrc;
.PP
.B int isnanf (fsrc)
.br
.B float fsrc;
.SH Description
The
.PN isnand 
and 
.PN isnanf
routines return the value 1 for true if the argument dsrc or fsrc 
is a NaN; otherwise they return the value 0 for false.  
.PP
Neither routine generates any exception, even for signaling NaNs.
.PP
The
.PN isnan
function is implemented as a macro included in <ieeefp.h>.