FPCLASSIFY(P) POSIX Programmer's Manual FPCLASSIFY(P)
fpclassify - classify real floating type
int fpclassify(real-floating x);
The fpclassify() macro shall classify its argument value as NaN, infinite, normal, subnor-
mal, zero, or into another implementation-defined category. First, an argument represented
in a format wider than its semantic type is converted to its semantic type. Then classifi-
cation is based on the type of the argument.
The fpclassify() macro shall return the value of the number classification macro appropri-
ate to the value of its argument.
No errors are defined.
The following sections are informative.
isfinite() , isinf() , isnan() , isnormal() , signbit() , the Base Definitions volume of
IEEE Std 1003.1-2001, <math.h>
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 FPCLASSIFY(P)