Adding variables makes it simpler?
- To: mathgroup at smc.vnet.net
- Subject: [mg37813] Adding variables makes it simpler?
- From: Steve Gray <stevebg at adelphia.net>
- Date: Wed, 13 Nov 2002 01:13:17 -0500 (EST)
- Sender: owner-wri-mathgroup at wolfram.com
Hello group -
I am computing 32 matrix products P, each 5x5.
Each one is a product such as P= V5.V4.V3.V2.V1, where
each Vi can independently be either Di or xiEi, i=1,2,3,4,5,
so there are 32 possible products. Di and Ei are 5x5
matrices and xi are scalars. The matrices consist of
integers and (-1)^(n/5) where n is an integer.
I have two situations, one where all xi=1 and
another where the xi are left as symbols with no assigned
values.
I am looking for P's whose rows are all
equal, that is, of the form {{a,b,c...},{a,b,c..}....}. After doing
FullSimplify[P[[1]]-P[[2]]] etc., it appears that I get more
equal-row P's out of the 32 when the xi are UNassigned
(have no numeric value) than when I set all xi=1. This is the
opposite of what I would expect.
Could it be that having the unassigned variables
in the expressions allows FullSimplify to do a more complete
job, thus finding more equal rows?
I am grateful for any help.