MathGroup Archive 2004

[Date Index] [Thread Index] [Author Index]

Search the Archive

Symbolic matrix manipulation


Hi all

I wonder if anyone can help---I'm new to Mathematica.

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.

Thanks, 

Chris


  • Prev by Date: Plot3D animation problems.
  • Next by Date: Re: quaternions
  • Previous by thread: Re: Plot3D animation problems.
  • Next by thread: Re: Symbolic matrix manipulation