Re: Symbolic matrix manipulation

*To*: mathgroup at smc.vnet.net*Subject*: [mg46863] Re: Symbolic matrix manipulation*From*: David Gunter <spam at davidgunter.com>*Date*: Fri, 12 Mar 2004 02:02:47 -0500 (EST)*References*: <c238jv$ii5$1@smc.vnet.net> <c29888$52u$1@smc.vnet.net>*Sender*: owner-wri-mathgroup at wolfram.com

Does anyone have an answer to this that doesn't require access to a journal for which I have no subscription? Thanks, david Paul Abbott wrote: > In article <c238jv$ii5$1 at smc.vnet.net>, junk4 at microserf.org.uk (C Rose) > wrote: > > >>I'd like to know how one can perform symbolic matrix-vector >>manipulations in Mathematica, without having to specify the contents >>of the matrices or vectors. >> >>For example, imagine I have a vector-valued function >> >>f(x) = x^T A >> >>where A is a m x n matrix, x is an m-vector, and ^T indicates >>transposition >> >>How can I differentiate f(x)---or perform other symbolic operations >>using matrices or vectors---such that I get the result in terms of A >>and x (i.e. I don't want to have to specify that >>A={{a11, a12, a13}, {a21, a22, a23}, {a31, a32, a33}} or whatever). >> >>So, in the example above, I want Mathematica to tell me the answer is >> >>d/dx (f) = A >> >>I'd appreciate your advice on this matter. > > > See The Mathematica Journal 8(4) (2002): 529-531 > > Cheers, > Paul > -- Replace spam with david if you wish to send email to my directly.