[Dev-C++] Checking validity of float and double

[Glen C. <gc...@pa...>]

This isnt a dev-C++ specific question, but i am wondering if anyone =
knows how you check if a float or double carrys valid data.=20

My program runs fine most of the time but every now and again it spits =
out -NaN.
I figure its from uninitialised variables, however I cant track down =
where they enter the program without performing periodick checks at =
suspect locations.=20

So is there a function like=20
    bool validFloat(float num)  for instance?