Re: complex numbers
- To: mathgroup at smc.vnet.net
- Subject: [mg24445] Re: [mg24396] complex numbers
- From: BobHanlon at aol.com
- Date: Tue, 18 Jul 2000 00:58:46 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
In a message dated 7/12/2000 11:29:58 PM, Ruchi5ten at aol.com writes:
>when i ask for the Re or Im parts of the a numerical conjugate, mathematica
>(4.0) does the operation correctly, but for a conjugate made of symbols
>(such as a+bI) it does not recognize whether the variable is real or not.
> i've tried to set the variable with a pattern and a blank to indicate
>them as such (ie a_Real) but still, mathematica doesn't see a difference.
> what can i do to work around the problem?
>
x = a + b*I;
Re[x] // ComplexExpand
a
Im[x] // ComplexExpand
b
Conjugate[x] // ComplexExpand
a - I*b
Simplify[Re[x], Element[{a, b}, Reals]]
a
Simplify[Im[x], Element[{a, b}, Reals]]
b
FullSimplify[Conjugate[x], Element[{a, b}, Reals]]
a - I*b
Bob Hanlon