Re: Transformation rule problem

*To*: mathgroup at smc.vnet.net*Subject*: [mg58168] Re: Transformation rule problem*From*: Oliver Buerschaper <groo137vy at yahoo.co.uk>*Date*: Tue, 21 Jun 2005 06:02:41 -0400 (EDT)*References*: <d90slm$8tt$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

> Brute force to the rescue! > > rulen[a_, b_][d_] = a^n_*b^m_ :> d*(a^(n - 1)*b^(m - 1)); > rulea[a_, b_][d_] = a*b^m_ :> d*b^(m - 1); > ruleb[a_, b_][d_] = a^n_*b :> d*a^(n - 1); > > mySimplify[expr_, a_ b_ -> d_] := > (expr //. rulen[a, b][d]) /. {rulea[a, b][d], ruleb[a, b][d]} > > This only works when a and b are not "mixable", i.e. they are immediately > identifiable by sheer pattern matching. What do you mean by this? Oliver