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Re: complex conjugation by star

  • To: mathgroup at smc.vnet.net
  • Subject: [mg132611] Re: complex conjugation by star
  • From: Murray Eisenberg <murray at math.umass.edu>
  • Date: Sun, 20 Apr 2014 04:47:35 -0400 (EDT)
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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 at 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 at 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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