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Topic: complex conjugation by star
Replies: 7   Last Post: Apr 23, 2014 4:52 AM

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 Murray Eisenberg Posts: 2,105 Registered: 12/6/04
Re: complex conjugation by star
Posted: Apr 20, 2014 4:47 AM

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

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