Date: Apr 20, 2014 4:47 AM
Author: Murray Eisenberg
Subject: Re: complex conjugation by star
I don't see how your definition can be valid. When I type input

f_*:=f/.Complex[u_,v_]->Complex[u,-v]

I see a highlighted asterisk, indicating a syntax error.

On Apr 18, 2014, at 1:46 AM, Brambilla Roberto Luigi (RSE) <Roberto.Brambilla@rse-web.it> wrote:

> I have defined the following useful star complex-conjugation (common star exponent notation)

>

> f_*:=f/.Complex[u_,v_]->Complex[u,-v]

>

> and it works fine. For example BesselJ[2,x+I y]* gives BesselJ[2,x-I y] etc...(x,y defined/undefined).

> Also it is listable on number lists

>

> {1+i2, 5+i6}* gives {1-i2, 5-i6} .

>

> Unfortunately it does not work on symbols, i.e.

> A* gives A even if I have defined A as a complex number by means of Element[A, Complexes].

> Similarly if I define Element[{A,B,G}, Complexes]

>

> {A,B,G}* gives {A,B,G} and (A+B+G)* gives A+B+G.

>

> I'd like to obtain {A*,B*,G*} and A*+B*+G* ( ! )

>

> Is it possible to fix this deficiency, unpleasant in manipulating general expressions where is not known

> if symbols represent real or complex variables ?

>

> Many thanks!

> Rob

>

>

>

>

Murray Eisenberg murray@math.umass.edu

Mathematics & Statistics Dept.

Lederle Graduate Research Tower phone 240 246-7240 (H)

University of Massachusetts

710 North Pleasant Street

Amherst, MA 01003-9305