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Subject: Re: [ublas] Matrix view over a bunch of ublas::vector's
From: dariomt (dariomt_at_[hidden])
Date: 2010-06-24 12:11:53

> On Thu, Jun 24, 2010 at 13:21, <dariomt <at>> wrote:
> Hi list,Suppose I have an algorithm that works over a matrix expression.I also
have a bunch of M ublas::vector's all of size N, each representing a row of a
matrix.Is it possible to create a 'view' over those vectors to pass it to the
algo as a MxN matrix expression?In this context a 'view' means that I don't need
to copy the data in the vectors into a ublas::matrixAlso N >> M, both determined
at runtime (i.e. N and M are not compile time constants).Thanks!

Jesse Manning <manning.jesse <at>> writes:

> I'm not sure the exact layout of your code but as an alternative you could
store your vectors as a matrix instead of individual vectors. This will allow
you to work on the matrix as a whole easily and you could use
matrix_row/matrix_column view classes to operate on the individual vectors
inside the matrix when needed since both of these implement the
vector_expression concept. This is essentially what I am doing in one of my
projects and it seems to work well.

I already thought about that, but it means that those parts of code must work
with storage coming from an ublas::vector or from a row in a ublas::matrix, and
that is not possible at the moment.

Thanks anyway!