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Subject: Re: [ublas] bounded_vector redundant storage of size. (is this a bug?)
From: Gunter Winkler (guwi17_at_[hidden])
Date: 2008-10-26 15:42:10


Am Freitag, 24. Oktober 2008 17:09 schrieb johanngoetz:
> for small vectors (geometry vectors is what I have in mind) the
> bounded_vector and bounded_matrix look promising. Indeed, if I was
> only dealing with a handful of vectors at a time, this would be
> ideal. However, I am creating a fieldmap (of a magnetic field, say)
> which maps 3D vectors (position) to 3D vectors (the field).

Actually - uBlas is not the best choice if you are looking for (small)
fixed size vectors and matrices. uBlas is optimized for dynamic sizes.
Thus bounded_storage provides a limited but still dynamic storage on
the stack. In order to efficiently support fixed size object we need a
fixed_storage class and real fixed_vector and fixed_matrix.

Note: In order to store a lot of 3D-vectors you should use a 3-column
row major matrix. Thus you can easily express mappings as matrix vector
operations.

btw. you should have a look at tvmet:
http://tvmet.sourceforge.net/

mfg
Gunter