Cecil Moore wrote in message ...

Does it really hurt anything to remind everyone that +1 at 180 degrees
equals -1 at zero degrees?

No, and I already agreed with that in another posting in this thread.
Perhaps you missed it. But it's just flat wrong to claim that the
negative value for sqrt(x^2) can be correct when you know that the the
original value of x is not negative: x in this case is the magnitude
of a complex number, and that magnitude is real and never negative.

Not only is that wrong, but it's also potentially confusing to lurkers
who may read into it that the only two values of rho which can result
in |rho|=1 are rho=+1 and rho=-1, and that's wrong. Just do it right
and say that your square root = |rho| = +1 and not -1, because it's a
magnitude, and that rho then can be magnitude 1 at ANY phase angle,
not just 0 and 180.

None of which has anything to do with the two of you continuing to
squabble like a couple of young children.

Cheers,
Tom