Re: Symbolic matrix manipulation
- To: mathgroup at smc.vnet.net
- Subject: [mg46741] Re: Symbolic matrix manipulation
- From: Paul Abbott <paul at physics.uwa.edu.au>
- Date: Fri, 5 Mar 2004 01:46:36 -0500 (EST)
- Organization: The University of Western Australia
- References: <c238jv$ii5$1@smc.vnet.net>
- Sender: owner-wri-mathgroup at wolfram.com
In article <c238jv$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
--
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