"Chongkai Zhu" <xxxxxx@citiz.net> writes:

> What if we know (exactly) a number is an imaginary number, but only
> know ineaxtly it's magnitude?  "0+1.0i" seems nature.

Yes, but Scheme doesn't provide this.  Scheme's numeric system doesn't
allow for "partial exactness".  It's not special for complex numbers;
the same could be true for rationals: what if the numerator is known
exactly, and the denominator inexactly?

Thomas