
Ublas : 
From: Gunter Winkler (guwi17_at_[hidden])
Date: 20060706 04:38:49
Hello,
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();
++it1;
const_iterator2 it2 = it1.begin();
++it2;
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.
mfg
Gunter
PS: You may answer privately  I collect all votes ;)