infinity and nan values

Question

I use gcc-mingw,4.5.2 on Winows 7. printf of infinity and nan values causes 1.#INF00 and -1.#IND00 to appear in the screen ,instead of infinity && nan what could be a solution for this problem

UPD:I tried to use isinf and isnan macros :

C3861: 'isinf': identifier not found error 
C3861: 'isnan': identifier not found.

(I did include to math.h) What is the reason for this?

Answer 1

Use the isinf() and isnan() macros to test wheter a number is an infinite or a NaN.

Answer 2

Add the following to your program.cpp

#ifndef isinf
#define isinf(x) ((x)!=(x))
#endif


#ifndef isnan 
#define isnan(x) ((x)!=(x)) 
#endif

Answer 3

That's just how the standard library of your compiler treats those special values. If you want different treatment you need to write your own print function that detects the special values and prints the text that you desire.