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Ublas :

From: Gunter Winkler (guwi17_at_[hidden])
Date: 2006-07-06 04:38:49


Do you use the duality feature of ublas' matrix iterators?

That means create an iterator1, advance a few rows, create an iterator2 for
the current row, advance some columns, create an iterator1, advance to
another row:
matrix<double> A(n,n);
const_iterator1 it1 = A.begin1();
const_iterator2 it2 = it1.begin();
const_iterator1 it1a = it2.begin();

This feature is a major cause of the complexity of ublas' matrix iterators and
the (strange & still undocumented) find{1,2}(...) functions.

I wonder if anyone really _needs_ this behavior. For dense matrices one could
easily use indices and for sparse matrices one should never iterate
orthogonal to the storage layout.


PS: You may answer privately - I collect all votes ;-)