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Listing of LAPACK error codes

And Orlando D?hring writes:
The HTML-ized LAPACK functions are at http://www.netlib.org/lapack/explore-html/
although they may lag behind releases a little bit.  The page for
dsyevr.f is:
  http://www.netlib.org/lapack/explore-html/dsyevr.f.html

And the LAPACK mailing list is at lapack at cs.utk.edu, although as
with all such projects, responses may be a *long* time in coming.
The high-level drivers like DSYEVR dispatch to different internal
routines depending on what was requested.  That makes documenting the
error codes a little painful...

For some of the routines involved, INFO.eq.1 or 2 implies 1 or 2
entries didn't converge, either when reducing a tridiagonal to
diagonal, in bisection, or in inverse iteration.  For another, but
only if you're requesting the ilo-th through ihi-th eigenvalues, 2
would imply non-monotonic arithmetic, and I would be *very*
surprised.

So likely something somewhere didn't converge.  Picking parameters
that *always* converge for eigenvalues is an open problem.

Have you tried this on different platforms, or with different BLAS?
Can you release the data that causes the problem?

Jason
Message-ID: <87eiwl1kwm.fsf@sparse.dyndns.org>
In-Reply-To: <d3c1ff960903250629t7fcc5befn48f2bd25b2f54846@mail.gmail.com> ("Orlando Döhring"'s message of "Wed, 25 Mar 2009 13:29:56 +0000")