Re: Simplifying Conjugate[] with 5.2 Mac
- To: mathgroup at smc.vnet.net
- Subject: [mg59769] Re: [mg59725] Simplifying Conjugate[] with 5.2 Mac
- From: Pratik Desai <pdesai1 at umbc.edu>
- Date: Sat, 20 Aug 2005 03:14:16 -0400 (EDT)
- References: <200508190831.EAA27421@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
Steuard Jensen wrote:
>I've just upgraded from Mathematica 5.0 to 5.2 for the Mac, and I
>discovered that a notebook that ran fine before (finishing in ten or
>fifteen minutes) was now being tremendously slow. I'm sure I haven't
>tracked down everything that I need to fix by hand to speed it back up
>again (I did a lot of tuning when I wrote it), but it seems that part
>of the problem can be tracked back to what looks like a bug in
>Simplify[] (or at least an awfully annoying behavior).
>
>Specifically, I have used $Assumptions to define some variables as
>real. I apply Conjugate to various expressions, and then Simplify the
>results. In version 5.0, I _never_ saw a case in which Conjugate[]
>remained after this step. But in 5.2, I find that even simple forms
>like Conjugate[x + I y] often remain unsimplified. (Refine[x + I y]
>still seems to work, though.)
>
>I've cut and pasted a simple example below, and I'd be interested to
>know if other people experience the same behavior. I'd appreciate any
>advice or comments on how to handle this, or on where I should write
>to report this strange behavior to Wolfram if you think that's
>appropriate. Thanks in advance for any help you can give.
>
> Steuard Jensen
>
>------------------------------------------------------------
>
>In[1]:= $Assumptions={Element[{x,y},Reals]};
>
>In[2]:= Simplify[Conjugate[x]]
>
>Out[2]= x
>
>In[3]:= Simplify[Conjugate[I y]]
>
>Out[3]= -I y
>
>In[4]:= Simplify[Conjugate[x+y]]
>
>Out[4]= x+y
>
>In[5]:= Simplify[Conjugate[x+I y]]
>
>Out[5]= Conjugate[x + I y]
>
>In[6]:= Refine[Conjugate[x+I y]]
>
>Out[6]= x - I y
>
>------------------------------------------------------------
>
>
>
Simplify[Conjugate[x+I y]]//ComplexExpand
Should work, atleast it does on my 5.1.1. Win XP
Hope this helps
Pratik Desai
--
Pratik Desai
Graduate Student
UMBC
Department of Mechanical Engineering
Phone: 410 455 8134
- References:
- Simplifying Conjugate[] with 5.2 Mac
- From: sbjensen@midway.uchicago.edu (Steuard Jensen)
- Simplifying Conjugate[] with 5.2 Mac