check if a double is odd or not

[user923005]

pow(10,25)+1 is an odd value.  What will your fmod() expression
evaluate to?

It will be an even number on any system for which DBL_DIG is less than
25 (as well it should be).

I don't think that should surprise anybody. The long long type won't
fare any better there, either, unless your long long holds more than
18 digits (I guess there could be some systems with 256 bit long
long).

 

[lawrence.jones]

pow(10,25)+1 is an odd value.

Not in most floating-point implementations. Sufficiently large
floating-point values are always even.

-- Larry Jones

Who, ME? Who?! Me?? WHO... Me?! Who, me??? -- Calvin