apb@cequrux.com writes:

> a. What's the recommended way to normalise a floating point number,
>    converting from negative zero to ordinary zero, and from assorted other

"(floating number) + 0.0"  will do this.

A sum of positive and negative zeros makes a positive zero.
(see http://en.wikipedia.org/wiki/Negative_zero#Properties_and_handling)
-- 
ITOH Yasufumi