Re: [boost] Ann: Floating Point Utilities Review starts today

From: Johan Råde (rade_at_[hidden])
Date: 2008-02-27 10:32:37

> There is one other useful function worth having IMO:
> 
> template <class T>
> int sign(T x);
> 
> returns 0 (x is zero), +1 (x is > 0) or -1 (x is < 0).  This is trivial to 
> implement (lot's of old C code - for example the Numerical Recipies stuff - 
> implement this as a helper macro), and there's an undocumented version 
> currently in Boost.Math.  Is this worth integrating with Johan's code?  I've 
> found it quite useful in Boost.Math from time to time.

What should this function return for a NaN?

--Johan