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Ublas : |
From: Shawn D. Pautz (sdpautz_at_[hidden])
Date: 2006-05-17 12:32:26
I also would be interested in having a permutation matrix class like Dan
outlines below. Presumably the underlying storage would be compressed
or vector-based, but having matrix semantics would be quite helpful to me.
Shawn
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>Today's Topics:
>
> 1. permutation matrix type (Dan Elliott)
> 2. Re: permutation matrix type (Gunter Winkler)
> 3. fixed size matrix and vector (was: permutation matrix type)
> (Brian Budge)
>
>
>----------------------------------------------------------------------
>
>Message: 1
>Date: Tue, 16 May 2006 22:26:13 -0500
>From: Dan Elliott <c_reply_to_at_[hidden]>
>Subject: [ublas] permutation matrix type
>To: ublas_at_[hidden]
>Message-ID: <m1r72ttjqi.fsf_at_[hidden]>
>Content-Type: text/plain; charset=us-ascii
>
>Hello,
>
>I fear that my ignorance about that guts of uBLAS will be made glaringly obvious by this question...
>
>I see that the lu.hpp file has a data type permutation_matrix which inherits from the vector type. However, I would like to discuss the merits of creating a matrix permutation matrix type that would behave more like a matrix (e.g. matrix operators for right and left had operations). Permutation matrices could even fall under a larger family of transformation matrices!
>
>Operations of other types against this type could have specialized algorithms which take advantage of their particular structure. For example, if T were a permutation matrix, and S were diagonal, the operation transpose(T) * S * T has a predictable structure as it goes from left to right.
>
>So, I am looking for feedback on the insanity of my suggestion, refinements to my idea, and eventually assistance understanding the design of uBLAS enough to write the necessary code (plus help if there are other interested parties).
>
>Thank you, in advance, for your time.
>
>
>