Re: Usage of **
- To: mathgroup at smc.vnet.net
- Subject: [mg84723] Re: Usage of **
- From: "Michael Weyrauch" <michael.weyrauch at gmx.de>
- Date: Fri, 11 Jan 2008 04:43:06 -0500 (EST)
- References: <fm4sh7$c06$1@smc.vnet.net>
Hello, of course, you can do that. You can use **, which is Protected, Unprotect it and give it the properties you need, including things like (x*A)**(y*B)=x*y*(A**B)). Appart from the Attribute Flat, ** does not really have any rules attached, so you need to teach it the rules you want. It is save and does not break anything as far as I have experienced. I use it for implementing Grassmann algebras. Maybe it is better to use CircleTimes[] instead of **, then it looks more like your o in printed formulas. CircleTimes is not even Protected. Michael Weyrauch "Hauke Reddmann" <fc3a501 at uni-hamburg.de> schrieb im Newsbeitrag news:fm4sh7$c06$1 at smc.vnet.net... > I'm playing with a Temperley-Lieb algebra with three strings, > i.e. an operator o, two generators A and B and a scalar t. > (AoA=t*A,BoB=t*B,AoBoA=A,BoAoB=B.) > Unluckily, AoB!=BoA, *and* I want to define some "mixes" > like w*A+x*B+y*AoB+z*BoA and multiply them, o shall be linear. > So e.g. (w*A+x*B)oA=w*(AoA)+x*(BoA)=w*A+x*(BoA). > > How to implement? With o=** maybe (but does (x*A)**(y*B) > evaluate to x*y*(A**B)), and can I define "global rules" > that act automatically, just like I*I=-1)? > > -- > Hauke Reddmann <:-EX8 fc3a501 at uni-hamburg.de > Er-a svo gott sem gott kveða > öl alda sonum, því að færra veit > er fleira drekkur síns til geðs gumi. >