About -0 and type complex

[Michael D. Godfrey]

I would just like to ask if the following behavior seems right
to you.  And, is there a way to set the imaginary part of
a complex to -0?

octave:46> -(1-1)
ans = -0
octave:47> -(1-1) +0i
ans = 0
octave:48> -(1-1) -0i
ans = -0
==================
The obvious question is: why does the sign of the imaginary
part change the sign of the real part?  The math definitions for
arg(z) and |z| treat the real and imaginary parts symmetrically.

I have not found a standard for +-0 for complex, but it would
seem reasonable to treat the real and imaginary parts according
to the same rule.  And, is it a good idea to reduce a complex
with +-0 imaginary part to real?  Saves space, I know, but the
sign is lost.

Currently, for complex the rule is:
real  imag    result
 -0     -0         -0
 -0      0          0
  0     -0          0

In effect, there is no -0 imaginary part even though -0i affects
results.

I know that this seems pretty academic, but it is getting in the way
of my figuring out the correct corner values of atan2(y,x) for complex
arguments (another pretty academic pursuit. I know).

If you think this is good enough, I will just add it to the documentation
about -0.  At least, users should know what is supposed to happen.

Michael