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From Ted Dunning <ted.dunn...@gmail.com>
Subject Re: [math] RealLinearOperator and AbstractRealMatrix
Date Wed, 13 Jul 2011 22:01:09 GMT
Actually, this is a major issue.

Take, for instance, the example of considering a Lucene index as a linear
operator.  The number of rows is the number of documents (which is changing
as documents are added) and the number of columns is the number of unique
terms (which is also changing as documents are added).

Matrix multiplication consists of translating a (hopefully sparse) vector
into a query, running the query and interpreting the result as a (sparse)
vector.

This is just one of a host of similar application oriented definitions of a
LinearOperator, none of which define the number of rows and columns at
construction time.

I can still do a singular value decomposition of this linear operator

On Wed, Jul 13, 2011 at 1:52 PM, Phil Steitz <phil.steitz@gmail.com> wrote:

> This is not a huge issue, though, so I can live with it if you feel
> strongly that the fields should be persisted at the top level.
>

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