Reported any bugs in C-LAPACK routine DSPEVX?

From: Javier Almeida (javieralmeida_at_fis.ucm.es)
Date: 10/21/04 

Date: 21 Oct 2004 10:54:35 -0700

Hello. I'm using C++ in combination with LAPACK++ and C-LAPACK in my
programs but these past days, trying to diagonalize a matrix of
dimensions 106x106 , I've found something strange in the CLAPACK
routine dspevx: I do request the 53th lower eigenvectors to be
computed, but the routine returns only 52, error code 0 (no, error),
and no information about the missing one. This happens to be in
contradiction with the behaviour of the routine as exposed in its
documentation (obtained directly from the source code). Moreover, the
conflictive program performs an ammount of about 36000 calls to this
routine, and only twice behaves this way: one of them is for a matrix
(106x106), requested for 53 eigenvectors and returned 52. The other is
for a matrix (114x114), requested for 57 eigenvectors and returned 56,
both with error code 0 (I've noticed that in fact the routine fills
the missing eigenvector with a normalized vector of ones).

     I would appreciate if someone could tell me wether this routine
has been reported to have a bug or not, I would also like to know
which version of LAPACK was CLAPACK (found in www.netlib.org)
translated from.
         Feel free to write to my mail and thanks everybody.

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