From: David Abrahams (dave_at_[hidden])
Date: 2004-07-06 07:55:46
Deane Yang <deane_yang_at_[hidden]> writes:
> Michael Stevens wrote:
>> This is very odd. In linear algebra there is no such thing as a
>> matrix of matrices.
> Yes, there is. It's a linear transformation mapping
> a space of matrices to another space of matrices.
> But could Jeremy or David provide some examples of useful applications
> of such an object? They are immensely useful in pure mathematics;
> I would love to know how they arise in more practical areas.
They're used in numerical simulations in the frequency domain
(http://www.cercom.polito.it/Publication/Pdf/28.pdf), and they form
the basis for the validity of many blocked matrix operations. The
fact that you can view it as an optimization or an operation on a
matrix of matrices should mean that you can achieve better code reuse
in the library.
-- Dave Abrahams Boost Consulting http://www.boost-consulting.com
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