Math Forum Discussions

Allan Hayes

Posts: 1,508
Registered: 12/6/04

Re: [mg4720] HELP:problems simplifying big matrices
Posted: Sep 2, 1996 1:43 AM

Plain Text

"Stephen O'Sullivan" <so@cp.dias.ie>
[mg4720] HELP:problems simplifying big matrices
writes,
>>>>>>
I wish to simplify large matrices by identifying occurrences of
specific algebraic expressions and replacing them with a variable
name. The problem is that unless the expressions to be
replaced occur in precisely the form specified by the given
transformation rule it doesn't spot them. Any simple solutions?
<<<<<<<<

Stephen,
I wonder if something along the lines of

{1/x +x, (1+x^2)/x}/. r_/;MatchQ[Simplify[r],1/x +x] ->p

{p, p}

might help (you may need to use something else instead of Simplify).

Allan Hayes
hay@haystack.demon.co.uk