Negative integers

[Mikael Olofsson]

Derek Martin wrote:
> Zero is a problem, no matter how you slice it.  

I definitely agree with that. Depends on the the real problem that is 
behind the OP:s question.

> Zero can be considered
> positive or negative (mathematically, 0 = -0).

I've read quite a few articles written by mathematicians and 
mathematically oriented engineers, and my impression is that most of 
them, and therefore me included, use those words with the following meaning:

     Positive: >0
     Negative: <0

When zero is to be included, the following terms are used:

     Non-negative: >=0
     Non-positive: <=0

Using this convention, zero is neither positive nor negative. Wikipedia 
seems to agree with that:

     http://en.wikipedia.org/wiki/Positive_number

/MiO