Simplifying Conjugate[] with 5.2 Mac
- To: mathgroup at smc.vnet.net
- Subject: [mg59725] Simplifying Conjugate[] with 5.2 Mac
- From: sbjensen at midway.uchicago.edu (Steuard Jensen)
- Date: Fri, 19 Aug 2005 04:31:47 -0400 (EDT)
- Sender: owner-wri-mathgroup at wolfram.com
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
------------------------------------------------------------
- Follow-Ups:
- Re: Simplifying Conjugate[] with 5.2 Mac
- From: Pratik Desai <pdesai1@umbc.edu>
- Re: Simplifying Conjugate[] with 5.2 Mac