LAPACK-3.2.2 errata file
updated on Tue Aug 17 2010
maintained by J. Langou, U. Colorado Denver
maintained by J. Langou, U. Tennessee
LAPACK-3.2.2 errata file
CLAPACK-3.2.1 errata file
BLACS-1.1.patch3 errata file
ScaLAPACK-1.8.0 errata file
Wishlist
Corrected in SVN -- to be released in 3.2.3
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(*) improvement :: Replace the two xLAMCH with thread-safe ones
(*) svn :: r772
o replace non-thread-safe slamch and dlamch subroutines with thread-safe variants relying on FORTRAN 90 INTRINSIC
o contribution from Jason Riedy and Piotr Luszczek
o committed by Julie Langou (SVN revision r772, on Fri, July 2 2010)
(*) bug0060 :: Typo in TESTING/EIG/dchkee.f and TESTING/EIG/zchkee.f
(*) svn :: r768
o bug report by Ake Sandgren (HPC2N, Umea University) on Thu July 1 2010 to "lapack@cs.utk.edu".
o committed by Julie Langou (SVN revision r768, on Fri, July 2 2010)
(*) bug0062 :: Array out-of-bounds reference in xLAQR5
(*) svn :: r787
o bug report and fix from Mathew Cross (NAG) on Sat Aug 14 2010
o see forum topic 1949
o In the section of the code "Special case: 2-by-2 reflection (if needed)" the logical test
IF( BMP22 .AND. ( V( 1, M22 ).NE.ZERO ) )
must be split into a nested test
IF (BMP22) THEN, IF (V(1,M22).NE.ZERO) THEN...
If .NOT. BMP22 then M22 can exceed the second extent of V (and recall
that logical expressions can be evaluated in any order in Fortran).
o committed by Julien Langou (SVN revision r787, on Tue, Aug 17 2010)
Confirmed problems -- bug needs to be fixed!
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(*) bug0020 :: in xGESDD, workspace query can overflow for large matrices
o reported by Stephan Ripke (Broad Institute, Boston) on Thu May 21 2009
o confirmed by Julien Langou on Thu May 21 2009
o see forum topic 1418
(*) bug0022 :: workspace query bug with DGEJSV (when only left or right singular vectors desired)
o reported by Allin Cottrell on Tue Jan 15 2009
o confirmed by Julien Langou on Fri Jan 30 2009
o see forum topic 866
o all information sent to Zlatko Drmac
(*) bug0024 :: the notation A' is confusing for complex matrices. Does A' stand for A transpose of A Hermitian transpose?
o reported by Clint Whaley early July 2009
o LAPACK is not consistent in it use of the notation for transpose and Hermitian transpose.
o The use of LAPACK A' is not consistent with the BLAS useage.
o We note that the Matlab/Scilab/Octave convention is A' stands for
"conjugate transpose" and A.' stands for "transpose".
o In the Z routines, LAPACK uses the notation A' 669 times, it means "conjugate
transpose" most of the time but it means "transpose" a few times (maybe
10 times max, for BLAS-like routines). The notation A**H, A**T, A**N is
used 549 times, The notation A^T, A^N, A^H 19 times. (This is just for
the Z routines.)
o see Julien's emails
o vote on the lapackers mailing list:
A**T (or A^T) and A**H (or A^H): Clint Whaley, Jim Demmel, Sven Hammarling, Antoine Petitet, Daniel Kressner
A' (for A**H) and A.' for (A**T): Julien Langou
(I love to be that supported by the lapackers!)
(*) bug0057 :: Non-eigenvectors from DGEEV, problem in balancing
o bug report sent by Numpy team on April 22nd, 2010
o see forum topic 1818
o see follow-up on lapackers on April 22nd from Jim "bug in DGEHRD"
"The balancing is choosing to scale some rows/columns by factors like 1e18,
which rather amplifies tiny rounding errors in the (presumably correctly)
computed eigenvectors of the balanced matrix, when balancing is undone at the end.
The expert driver interface dgeevx would let the user disable balancing, until
we figure out whether this is a bug or a feature, I'm not sure which."
(*) bug0061 :: zgehrd.f is overflowing the maximum size in bytes of the largest array that
can be put on the stack with gfortran (=> leads ,e.g., to non-reproducible and uncorrect execution
of zgeev in multithreaded context
o bug report by Victor Liu on Tuesday August 03rd, 2010
o lapackers involved in the bug fix process: Julie and Julien Langou and Mathieu Faverge
o bug fix by Victor Liu on Wednesday August 04th, 2010
o see forum topic 1930
o two outstanding issues: (1) how do we go to fix this?, (2) more LAPACK subroutines might be concerned.
Bug reports -- bug needs to be confirmed!
=========================================
(*) bug0026 :: problem when playing with DGEEV and gfortran optimization flags
o reported by Pauli Virtanen (scipy team) on Sat Dec 06 2008 (email to lapack@cs.utk.edu)
o see: email from Pauli Virtanen
see: http://scipy.org/scipy/scipy/ticket/709
(*) bug0027 :: misleading comment in the header of DGHEQZ, the 2x2 block of the real Schur form are not as claimed
o reported by Vasile Sima on Tue Jan 27 2009
o see: email from Vasile
o more information:
more specifically Vasile is reporting that the comments:
* [...] H contains the upper quasi-triangular
* matrix S from the generalized Schur factorization;
* 2-by-2 diagonal blocks (corresponding to complex conjugate
* pairs of eigenvalues) are returned in standard form, with
* H(i,i) = H(i+1,i+1) and H(i+1,i)*H(i,i+1) < 0.
are not correct
(*) bug0028 :: failure of convergence of DHGEQZ for some specific matrix pencils
o reported by Vasile Sima on Thu Jan 22 2009
o see: email from Vasile
o more information at: lapack known issues
(*) bug0029 :: problem of WORKSPACE query with DSTEDC
o reported by Tiago Requeijo on Mon Mar 30 2009
o see forum topic 1389
o Julie : CANNOT REPRODUCE THE PROBLEM
(*) bug0030 :: line 641 of DTGSY2 (present as well in STGSY2, ZTGSY2, CTGSY2)
o reported by Zbigniew Leyk (College Station, TX) on Mon Jun 01, 2009
o see forum topic 1445
(*) bug0032 :: matrix splitting problem with dstebz and sstebz
o bug report sent by Phil DeMier (IBM) on Mon 29 Jun 2009 to "lapack@cs.utk.edu".
"matrix splitting problem with dstebz and sstebz"
o see Phil DeMier's email and Phil DeMier's test code
(*) bug0033 :: failure of zheevd on a specific matrix
o bug report sent by Cezary Sliwa (Instytut Fizyki PAN, Poland) on Thu 2 Jul 2009 to "lapack@cs.utk.edu".
o see Cezary Sliwa's test code, Cezary Sliwa's matrix, and
Cezary Sliwa's email.
(*) bug0034 :: comments in SSPTRF not correct
o clarification asked by "sarnath" on Thu Jul 02 2009
o confirmation of bug by "sarnath" and Julien Langou on Fri Jul 03 2009
o The statement "JMAX is the column-index of the largest off-diagonal element in row IMAX" is not correct
o see forum topic 1553
(*) bug0035 :: dlarfb.f and likes
o bug report sent by Michael Chuvelev (Intel) on Tue 21 Jul 2009 to "lapack@cs.utk.edu".
"Bug in LAPACK 3.2 dlarfb.f and likes"
o see Michael Chuvelev and Julie's emails, q.dat,
tau.dat, and test_dorgql.f
(*) bug0036 :: scaling in xSTEQR, xSTERF
o bug report sent by Pat Quillen on Fri 24 Jul 2009 to "lapack@cs.utk.edu".
"Scaling in xSTEQR, xSTERF"
o see Pat Quillen's email, quillen dsteqr.f.
(*) bug0037 :: xLARFP and scaling
o bug report sent by Pat Quillen on Wed 29 Jul 2009 to "lapack@cs.utk.edu".
"xLARFP and scaling"
o see Pat Quillen's email, and quillen dlarfp2.f,
o see Sven Hammarling's email
o see Pat Quillen's email, quillen dlarfp3.f, and quillen dlarf2.f.
(*) bug0039 :: faulty workspace queries in GEESX
o bug report from Mathew Cross on Tue 18 Aug 2009
o see forum topic 1602
(*) bug0040 :: Q referenced in real TGSENs when WANTQ .FALSE.
o bug report from Mathew Cross on Tue 18 Aug 2009
o see forum topic 1604
(*) bug0056 :: Non-orthogonal eigenvectors returned from DSYEVR
o bug report sent by by Scipy team on April 22nd
o see LAPACK Mailing list msg 874
o Julie cannot reproduce the problem on her machine with 3.2.1 and Ref BLAS
Deprecated routines
===================
(*) dead code :: xLAHRD is now replaced by xLAHR2, xLAHRD is a dead code since LAPACK 3.1
o xLAHRD will be removed at some point in the future from the distribution
Previous Errata (LAPACK 3.2.2)
==============================
o Wed Aug 04 2010 (LAPACK-3.2.2)
o Fri Jul 02 2010 (LAPACK-3.2.2)