Re: Patterns Problem

*To*: mathgroup at smc.vnet.net*Subject*: [mg28170] Re: [mg28151] Patterns Problem*From*: BobHanlon at aol.com*Date*: Tue, 3 Apr 2001 02:37:48 -0400 (EDT)*Sender*: owner-wri-mathgroup at wolfram.com

See on-line help for NonCommutativeMultiply Bob Hanlon In a message dated 2001/4/2 2:36:19 AM, jkawczak at math.uncc.edu writes: >I am trying to force an output to appeat in a certain way, but without >much >success. Here is my problem. > >First, how to "teach" M. that some symbols are matrices, vectors, etc... >and >that the laws of the real arithmetic do not apply. > >Let's take A to be a matrix, and u and v, vectors. >I would like to have the following: > >u A (u - )=u A u -u A > >the operator is not symmetric. Whenever I do this oparation I get >something like >A u u or A u ^2. I just cannot force the order to be correct! > >Also, I would like to have the oparator to >be iterative, i.e. > >v A {(u A (u - ) -<u A (u - )>} >=v A u A u - v A u A - v A <u A u> + v A u A , and so on.