Checking if a double (or float) is NaN in C++

Question

Is there an isnan() function?

PS.: I\'m in MinGW (if that makes a difference).

I had this solved by using isnan() from , which doe

Answer 1

There is also a header-only library present in Boost that have neat tools to deal with floating point datatypes

#include 

You get the following functions:

template  bool isfinite(T z);
template  bool isinf(T t);
template  bool isnan(T t);
template  bool isnormal(T t);

If you have time then have a look at whole Math toolkit from Boost, it has many useful tools and is growing quickly.

Also when dealing with floating and non-floating points it might be a good idea to look at the Numeric Conversions.