==============
Changes: 2.1.6
==============


.. rubric:: General:

-  Added support for Cray X1
-  Added option '-suggest' to petscarch script. It suggests some
   possible PETSC_ARCHes to use
-  Installation instructions are rewritten

.. rubric:: Vec:

-  VecNorm now caches NORM_2
-  Added VecStrideScale(), VecStrideGather(), VecStrideScatter()
-  Added VecBlockNorm(),VecBlockMax(),VecBlockMin(),VecBlockScale()

.. rubric:: Mat:

-  The interface to external packages that support direct solvers has
   been reorganized. This is implemented using new matrix types
   MATSEQAIJSPOOLES, MATMPIAIJSPOOLES, MATSEQSBAIJSPOOLES,
   MATMPISBAIJSPOOLES, MATSUPERLU, MATSUPERLU_DIST,
   MATUMFPACK,MATESSL, MATLUSOL, MATAIJMUMPS, MATSBAIJMUMPS,
   MATDSCPACK
-  Added new convenience matrix types which automatically switch
   between Seq and MPI implementations depending on the size of the
   communicator used during creation: MATAIJ, MATBAIJ, MATSBAIJ,
   MATMAIJ, MATDENSE, MATBDIAG
-  Changed default matrix-free compute h to use WP since it uses
   fewer reductions
-  Replace the datatypes MatLUInfo and MatILUInfo by MatFactorInfo
-  Added cholesky support to SeqAIJ
-  Added support for SUBSET_NONZERO_PATTERN with MatAXPY for AIJ &
   BAIJ
-  Added MatIsSymmetric() for AIJ
-  Added LDA support in SeqDense
-  The ncols argument made optional in MatGetRow()
-  Added MAT_KEEP_ZEROED_ROWS for MPIROWBS
-  Removed -aij_oneindex support from AIJ code
-  Added MatPartitioningSetPartitionWeights() - usable with ParMetis
-  MatGetSubMatrices() now works for ROWBS

.. rubric:: PC:

-  Added PCICCSetDamping() or -pc_icc_damping
-  Added -pc_constant_null_space
-  Added PCILUSetShift() or -pc_ilu_shift to support damping using
   the identity
-  Added PCLUSetShift() or -pc_lu_shift to support damping using the
   identity
-  Added PCICCSetShift() or -pc_icc_shift to support damping using
   the identity

.. rubric:: KSP:

-  Added a new ksp_type LGMRES
-  Added KSPSetComputeSingularValues() support to ksp_type FGMRES

.. rubric:: TS:

-  Added support for Runge-Kutta using ts_type TS_RUNGE_KUTTA

.. rubric:: DMMG:

-  -dmmg_jacobian_period -1 => jacobian is frozen after initial
   construction

.. rubric:: DA:

-  Allow user preallocation of jacobian using DASetGetMatrix()
-  DAGetMatrix now correctly returns the requested type.
-  -mat_type typename overloads the requested type for DAGetMatrix

.. rubric:: SYS:

-  Added new viewer_type PETSC_VIEWER_NETCDF, PETSC_VIEWER_HDF4
-  PETSc error handlers now trap many more signals.

.. rubric:: Fortran:

-  PetscPushErrorHandler() and PetscPopErrorHandler() now supported
-  PetscPrintf() and PetscSynchronizedPrintf() now work in fortran
   with a single string

.. rubric:: External Packages:

-  Added TSPVodeGetParameters()
-  Parmetis-3 support added using MatPartitionSetNParts(),
   ISPartitionCount()
-  MUMPS support added, including complex (using mat_type
   MATAIJMUMPS, MATSBAIJMUMPS)
-  Updated SuperLU_DIST interface to SuperLU_DIST_2.0
-  Added Spooles complex support
-  Added Spooles cholesky for SeqAIJ
-  ADIC: ad_GRAD_MAX is now set in the application and compiled into
   code when compiling appplication
-  The following variable names - in the buildsystem are changed -
   that correspond with SuperLU_DIST SUPERLUDIST_INCLUDE ->
   SUPERLU_DIST_INCLUDE SUPERLUDIST_LIB -> SUPERLU_DIST_LIB
   PETSCHAVE_SUPERLU -> PETSC_HAVE_SUPERLU