negative base raised to fractional exponent

[Bjoern Schliessmann]

 schaefer.mp at gmail.com wrote:

> Thank you for this. Now I need to somehow express this as a real
> number. For example, I can transform the real and imaginary parts
> into a polar coordinate giving me the value I want:
> 
> z = sqrt( real_part**2 + imaj_part**2 )
> 
> but this is an absolute terms. 

Not really. It is just the "absolute value" which is a property of
the complex number; it is (as already stated) by definition always
positive. There doesn't exist any underlying "real" value from
which a sign is stripped to yield the absolute value of z.

> How does one determine the correct sign for this value?

In this case, the background (what you model using this complex
number) is of great importance. 

Consider learning more about complex numbers; especially about how
they can be represented as a point on the complex plane
(<http://en.wikipedia.org/wiki/Complex_plane>), understanding this
makes understanding and dealing with complex numbers much easier. 

Regards,


Björn

-- 
BOFH excuse #31:

cellular telephone interference