NAME

       diag - get diagonal part of a matrix

DESCRIPTION

       This function get the diagonal part of a matrix.

               csr<Float> a;
               dia<Float> d = diag(a);

TODO

       Build a csr matrix from a diagonal one or from a vector:

               dia<Float> d;
               csr<Float> a = diag(d);
               vec<Float> u;
               csr<Float> b = diag(u);

IMPLEMENTATION

       template<class T, class M>
       dia<T,M> diag (const csr<T,M>& a)

COPYRIGHT

       Copyright  (C) 2000-2018 Pierre Saramito <Pierre.Saramito@imag.fr> GPLv3+: GNU GPL version
       3 or later <http://gnu.org/licenses/gpl.html>.  This is free software:  you  are  free  to
       change and redistribute it.  There is NO WARRANTY, to the extent permitted by law.