Isinf - Analog Devices VISUALDSP++ 3.5 Manual

C Run-Time Library Reference

isinf

test for infinity
Synopsis
#include <math.h>
int isinff(float x);
int isinf(double x);
Description
The function returns a zero if the argument is not set to the IEEE
isinf
constant for
+Infnity
non-zero value.
Error Conditions
The function does not return or set any error conditions.
isinf
Example
#include <stdio.h>
#include <math.h>
static int fail=0;
main(){
/* test int isinf(double) */
union {
double d; float f; unsigned long l;
} u;
#ifdef __DOUBLES_ARE_FLOATS__
u.l=0xFF800000L; if ( isinf(u.d)==0 ) fail++;
u.l=0xFF800001L; if ( isinf(u.d)!=0 ) fail++;
3-76
or ; otherwise, the function will return a
-Infinity
VisualDSP++ 3.5 C/C++ Compiler and Library Manual
for ADSP-219x DSPs