LAPACK 3.3.1
============

Release date: Mo 04/18/2011.

This material is based upon work supported by the National Science Foundation
and the Department of Energy under Grant No. NSF-OCI-1032861 (2010-2013 est.),
NSF-CCF-00444486 (2005-2008 est.), NSF-CNS-0325873 (2004-2009 est.),
NSF-EIA-0122599 (2001-2004 est.), NSF-ACI-0090127, DOE-DE-FC02-01ER25478,
DOE-DE-FC02-06ER25768.

LAPACK is a software package provided by Univ. of Tennessee, Univ. of
California Berkeley, Univ. of Colorado Denver and NAG  Ltd.

1. Support and questions:
-------------------------

http://icl.cs.utk.edu/lapack-forum/

2. LAPACK 3.3.1: What's new
-------------------------

.IMPORTANT
****
This is just a *BUG FIX release* and also we tried to improve the *CMAKE build system*.

**** 
  
3. External Contributors
------------------------

    * Chuck Atkins and Brad King (Kitware, Inc)

4. Thanks
---------

.Thanks for bug-report/patches/suggestions to:
 * Nadezhda Mozartova (Intel, USA)
 * Alexander Kobotov (Intel, USA)
 * John Tellefson (Salina, KS, USA)
 * Inge Gutheil (Juelich Supercomputing Centre, Germany)
 * Christof Voemel
 * Paul Roberts (NAG, UK)
 * Pat Quillen (Mathworks, USA)
 * Michael Chuvelev (Intel, USA)
 * Vasile Sima (National Institute for Research & Development in Informatics, Romania)
 * Clint Whaley (University of Texas at San Antonio, USA)
 * Allin Cottrell (Wake Forest University, USA)
 
.and our users of the LAPACK forum:
 * squartz
 * fabioaffinito
 * sarnath

5. Developer list
-----------------

.Principal Investigators

    * Jim Demmel (University of California at Berkeley, USA)
    * Jack Dongarra (University of Tennessee and ORNL, USA)
    * Julien Langou (University of Colorado Denver, USA)

.LAPACK developers involved in this release

    * Julie Langou (University of Tennessee, USA)
    * Rodney James (University of Colorado Denver, USA)

6. Improvment to the CMAKE build
--------------------------------

.Here's a summary of the CMake changes:
* Added a FindBLAS module to easily search for and link against various optimized BLAS implementations
* Added proper default compiler flags for various commercial Fortran compilers
* Check for and disable SIGFPE handlers (LAPACK code handles these internally) on known compilers
* Remove testing drivers and BLAS source from nightly code coverage to get a more accurate representation of the LAPACK code getting exercised
* Suppress harmless warning messages for various platforms and compilers
* Added 28 nightly builds (http://my.cdash.org/index.php?project=LAPACK)
* Standardized binary output locations to play nicely when building Windows DLLs
* Cleaned up CMake packaging to allow find_package(LAPACK) in applications
* Added missing link dependencies for test libraries

7. Level-3 BLAS hermitian indefinite inversion: This enables better performance for CHETRI and ZHETRI.
------------------------------------------------------------------------------------------------------
.lapacker

Julie Langou

.contribution

Level-3 BLAS hermitian indefinite inversion (CHETRI and ZHETRI).
See link:lapack-3.3.0.html[Release 3.3.0 section 6.2 for more details]

8. Bug Fix
----------

== [green]*bug0078* :: DBDSDC problem with orthogonality of U in certain cases
 * bug report sent by duncanpo on April 4th 2011
 * see forum topic 2326
 * decreased EPS by a factor of 0.9 to correct problem with orthogonality of U in certain cases
 * corrected by Rodney on Tue April 7th 2011

== [green]*bug0077* :: [DS]GESVD Minimum Worksize comments need clarification
 * bug report sent by squartz on Sep 19th
 * see forum topic 2011
 * corrected by Julie on Tue April 5th 2011

== [green]*bug0076* :: Problem in ?(sy/he)tri2 when nbmax greater than n
 * bug report sent by nmozarto on Mar 4th
 * see forum topic 2223
 * corrected by Julie on Fri March 4th 2011

== [green]*bug0075* :: not orhtogonal: eigenvectors of a symmetric matrix with DSYEV 
 * bug report sent by fabioaffinito on Feb 8th
 * see forum topic 2169
 * corrected by Rodney on Thu March 3rd 2011
 * The bug appears only when the matrix is diagonalized by using the upper half, and when the leading dimension n>200 approx.
 * User gave test program see: link:http://icl.cs.utk.edu/lapack-forum/viewtopic.php?f=13&t=2169&p=6237#p6237[here]
 * Come from change in version 3.2 [link:http://netlib.org/lapack/lapack-3.2.html[Release Notes]]
 * related to 0035

== [green]*bug0074* :: ?sysv and ?hesv
 * bug report sent by Alexander Kobotov on Feb 8th
 * see forum topic 2168
 * corrected by Julie
 * In LAPACK 3.3 ?(SY/HE)SV are updated to use TRS2. The TRS2 requires WORK(N) to operate, whereas in SV requirements for LWORK just to be >=1. There is no any check in SV if LWORK>=N, the array WORK just passed as it is to TRS2. So if LWORK<N a crash could occur while executing TRS2 due to overuse of allocated workspace.
 * I guess for the case of LWORK<N just previsous Level2 based ?(SY/HE)TRS should be used.

== [green]*bug0073* :: secondtst.f and dsecnd.f
 * bug report sent by John Tellefson on Feb 7th
 * email sent to lapack mailing list, user provided fix.
 * corrected by Julie
 * We went ahead and remove the dummy subroutine in those timing for the last LAPACK version because we did not find a machine or compiler that still had the problem. I guess we were too optimistic.
 * also committed the "cosmetic" modifications suggested by user as they make the program easier to modify.

== [green]*bug0072* :: cchkhs.f and zchkhs.f
 * bug report sent by Inge Gutheil on Feb 3rd
 * email sent to lapack mailing list, user provided fix.
 * corrected by Julie
 * Add IF statement to prevent calculation if N=0
 
== [green]*bug0071* :: slarre and dlarre 
 * bug report sent by Christof Voemel on Jan 31th
 * email sent directly to Julie and Julien, Christof provided fix.
 * corrected by Julien
 * Add a line to prevent TAU from becoming zero

== [green]*bug0070* ::  IWORK dimension is incorrect
 * bug report sent by nmozarto on Jan 27th
 * see link:http://icl.cs.utk.edu/lapack-forum/viewtopic.php?t=1930[forum topic 2156]
 * confirmed by Julie and corrected by Brian Sutton
 * The correct dimension is (M-R), in which R is the smallest of P, M-P, Q, and M-Q.
 * An M-by-M matrix is partitioned into a 2-by-2 block structure. The
 * dimensions of the blocks are P-by-Q, P-by-(M-Q), (M-P)-by-Q, and
 * (M-P)-by-(M-Q). IWORK is involved in the permutation of rows or
 * columns of these blocks, and it is the largest block, in terms of
 * number of rows or columns, that determines the size of IWORK.

== [green]*bug0069* ::  sytri2x is writing on other part of A
 * bug report sent by nmozarto on Jan 27th
 * see link:http://icl.cs.utk.edu/lapack-forum/viewtopic.php?t=1930[forum topic 2156]
 * confirmed by Julie and corrected by Julie

== [green]*bug0068* ::  Need to add LDA in *sytrs2
 * bug report sent by nmozarto on Jan 27th
 * see link:http://icl.cs.utk.edu/lapack-forum/viewtopic.php?t=1930[forum topic 2157]
 * confirmed by Julie and corrected by Julie

== [green]*bug0067* ::  Need to add LDA in *syswapr
 * bug report sent by nmozarto on Jan 24th
 * see link:http://icl.cs.utk.edu/lapack-forum/viewtopic.php?t=1930[forum topic 2150]
 * confirmed by Julie and corrected by Julien
 * Need to add LDA in *syswapr routines and update testing to test having LDA

== [green]*bug0066* ::  bugs in {s,d}gejsv 
 * bug report sent by Paul Roberts on Oct 21st
 * reported to Zlatko Drmac and corrected by Zlatko Drmac
 * see link:http://icl.cs.utk.edu/lapack-forum/archives/lapack/msg00949.html[ LAPACK Mailing list msg 049]

== [green]*bug0036* :: scaling in xSTEQR, xSTERF
 * bug report sent by Pat Quillen on Fri 24 Jul 2009 to "lapack@cs.utk.edu".
      "Scaling in xSTEQR, xSTERF"
 * see link:Errata/bug_lapack_3.2.1_0036/025.txt[Pat Quillen's email], link:Errata/bug_lapack_3.2.1_0036/quillen_dsteqr.f[quillen dsteqr.f].
 * Correction: "changed matrix norm to 'M' (max) from 'I' (inf) for scaling of input matrix
 * and added check for zero norm in xSTERF (the xSTEQR already had this check)"
 * confirmed by Rodney and corrected by Rodney

== [green]*bug0035* :: dlarfb.f and likes
 * 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"
 * see link:Errata/bug_lapack_3.2.1_0035/024.txt[Michael Chuvelev and Julie's emails], link:Errata/bug_lapack_3.2.1_0035/q.dat[q.dat],
      link:Errata/bug_lapack_3.2.1_0035/tau.dat[tau.dat], and link:Errata/bug_lapack_3.2.1_0035/test_dorgql.f[test_dorgql.f]
 * confirmed by Rodney on Tue Feb 22 2011
 * corrected by Rodney on Thu March 3rd 2011

== [green]*bug0034* :: comments in SSPTRF not correct 
 * clarification asked by "sarnath" on Thu Jul 02 2009
 * confirmation of bug by "sarnath" and Julien Langou on Fri Jul 03 2009
 * The statement "JMAX is the column-index of the largest off-diagonal element in row IMAX" is not correct
 * see link:http://icl.cs.utk.edu/lapack-forum/viewtopic.php?f=2&t=1553[forum topic 1553]

== [green]*bug0027* :: misleading comment in the header of DGHEQZ, the 2x2 block of the real Schur form are not as claimed
 * reported by Vasile Sima on Tue Jan 27 2009
 * see: link:Errata/005.txt[email from Vasile]
 * 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) &lt; 0.
-----
are not correct

 * confirmed by Rodney and corrected by Rodney

== [green]*bug0024* :: the notation A' is confusing for complex matrices. Does A' stand for A transpose of A Hermitian transpose?
 * reported by Clint Whaley early July 2009
 * LAPACK is not consistent in it use of the notation for transpose and Hermitian transpose.
 * The use of LAPACK A' is not consistent with the BLAS useage.
 * We note that the Matlab/Scilab/Octave convention is A' stands for
      "conjugate transpose" and A.' stands for "transpose".
 * 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.)
 * see link:Errata/023.txt[Julien's emails]
 * 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!)
 * corrected by Julie

== [green]*bug0022* :: workspace query bug with DGEJSV (when only left or right singular vectors desired)
 * reported by Allin Cottrell on Tue Jan 15 2009
 * confirmed by Julien Langou on Fri Jan 30 2009
 * see link:https://icl.cs.utk.edu/lapack-forum/viewtopic.php?f=2&t=866[forum topic 866]
 * all information sent to Zlatko Drmac
 * Corrected by Zlatko Drmac


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