[Date Index]
[Thread Index]
[Author Index]
Forcing Re[]'s to be Real
*To*: mathgroup at smc.vnet.net
*Subject*: [mg18223] Forcing Re[]'s to be Real
*From*: afoglia at hal.physics.ucsb.edu (Anthony Foglia)
*Date*: Tue, 22 Jun 1999 20:41:15 -0400
*Organization*: University of California, Santa Barbara
*Sender*: owner-wri-mathgroup at wolfram.com
I seem to have found an interesting problem involving computing the
real part of complex numbers. (Interesting, in that it wasn't there a few
weeks ago when I ran the (as-far-as-i-can-remember) exact same code.)
I have a complex function:
k[w] := Sqrt[w^2 (1 + (2 / (1 + I w)))]
I want to graph the real and imaginary parts, but Mathematica doesn't want
to express the Re[k[w]] as a real number. What do I mean? Well, if I
type:
Re[Sqrt[1+I]]
I get out
Re[Sqrt[1+I]]
Same if I do Re[ComplexExpand[Sqrt[1+I]]], or Re[(1+I)^(1/2)]. But if I
enter:
Re[ComplexExpand[(1+I)^(1/2)]
Mathematica is kind enough to respond with:
2^(1/4) Cos[Pi/8]
I'm certain that this is the root of my problem, but I'll be damned if I
know why Mathematica doesn't like it now, but did a few weeks ago. Any
help?
--Anthony
Prev by Date:
**Latex**
Next by Date:
**Canceling square roots with Simplify**
Previous by thread:
**Re: Latex**
Next by thread:
**Re: Forcing Re[]'s to be Real**
| |