Testing for infinity

[jwakeman]

Hi,

I would like to test if the value returned in a double is infinity. I tried comparing if the bytes of the double were equal to 0x7F00000000000000 and I tried if(atof("infinity") == doubleVal) but the first always returned false and the second always returned true. I see a function infinity( ) in mathALib that looked like it might be helpful but I'm not sure how to include that lib. I can compile using that function but get a link error once on the cRIO. So really two questions here:

1. How to link with a lib like mathALib?
2. A nice way to check for infinity (and maybe NaN while your at it)?

Thanks!