Changes

v2.4

• Added factorization of inverse matrix , enabling vector solves using matrix vector mult. instead of forward/backward solves with much better parallel speedup.
• Significant improvements in parallel performance of matrix inversion.
• Improved performance of LU, matrix-vector mult., forward/backward solves.
• Added function nearfield_sparse to extract 𝓗-matrix nearfield as sparse matrix.
• Switched to adaptive_split_axis as default for clustering.
• Minor Changes:
  • Additional options for matrix visualization (colormap, etc.)
  • Basic VTK output of block clusters.

v2.3

v2.3.2

• fixed various bugs and race conditions
• extended ctors of various matrix classes to accept optional value type field
• added example on how to assemble block matrices

v2.3.1

• Fixed two bugs in point-wise LU.
• Solver changes:
  • Refactored solver classes (no interface changes); added TRichardson to replace TSolver in the future.
  • Fixed inconsistent computation of residual norm in solvers. Now Richardson, CG and BiCG will compute standard residual norm, while MINRES and GMRES compute preconditioned residual norm.
  • Made initialisation of start vector in solver classes optional (function initialise_start_value)
• Added function "diagonal" to extract diagonal of a matrix.
• Added example "spectrum" to compute spectrum of graph Laplacian.

v2.3.0

• Fixed issues when solving dense matrices (used in new example for many RHSs).
• Modified THiLoFreqGeomAdmCond: now maximal number of wavelengths per cluster is tested.
• Refactored geometrical clustering classes and partitioning strategies, thereby fixing several issues.
• C++11 changes:
  • most object creating functions now return std::unique_ptr,
  • replaced typedef by using,
  • added iterators for TIndexSet, TNodeSet, TGraph, TProcSet (for range based for).
  • Note: needs at least GCC v4.7 or equivalent!
• Added parameter to algebraic clustering in C bindings to define partitioning algorithm (BFS, multi level, METIS or Scotch).
• Fixed issues with progress bar during factorisation (wrong block count).
• Removed BSP style comminucation functions (MPI only now).
• Finished conversion to new packed_t SIMD type. Using SSE3 instead of SSE2.
• Added lock to TScotchAlgPartStrat because Scotch is not multi thread safe.

v2.2

• Removing implicit reordering of unknowns during matrix-vector multiplication to fix inconsistent behaviour. Please use permutations from cluster trees or 𝓗-matrices to reorder vectors or TPermMatrix to represent permuted matrices instead.
• Speedup improvements for matrix inversion. Triangular inversion and matrix multiplication available in standard user interface.
• Import/export from/to CCS/CRS matrices simplified.
• Simplified (and faster) mutex wrapper.
• Several C++11 changes.

v2.1

• Removing reference counters in BLAS interface due to major performance issue on multi-core (-socket) systems. See BLAS/LAPACK Interface on how to use the modified interface (and avoid errors).
• New, scalable matrix-vector multiplication implemented.
• Using generic datatype for SIMD instructions, thereby enabling generic SIMD algorithms, e.g. for BEM kernels, and fast adoptation of new SIMD instructions, e.g. AVX2.
• Started to use block-wise operations if dense matrices are combined with blocked matrices (e.g. during matrix multiplication) instead of vector operations.
• Removed TVirtualVector (replaced by TScalarVector).
• Fixed issue with MatrixMarket format (leading whitespaces).

v2.0

v2.0.2

• fixed race condition in C bindings
• fixed issue with initialisation of static variables

v2.0.2

• bug fixes

v2.0

• Major Changes
  • Switched from OpenMP to Threading Building Blocks as interface to shared memory parallelism, thereby also changing most algorithms to task-based parallelism.
  • Reducing dependency on external libraries by using C++11 features. Also replacing some classes by default C++ versions (finally removing old code).
  • Alternative, non-recursive, level-wise ℋ-LU factorisation based on explicit block dependencies, which provides far better speedup on many-core systems, e.g. Intel MIC architecture.
  • New ℋ-LU factorisation algorithm also applicable in distributed environments, yielding better load-balancing (albeit with limited speedup).
  • Added support for multiple CPUs to many algorithms, e.g. in clustering, norm computations, matrix-vector multiplication and solves, ℋ²-convertion.
• Minor Changes
  • Optimised BEM kernels for Intel MIC architecture.
  • Introduced TLinearOperator for operators not supporting TMatrix functionality, e.g. factorised matrices.
  • HLIBpro file format changed due to internal changes and due to some bugs in the format. However, backward read compatibility for most files written with earlier versions is kept.
  • Added Support for Cairo library, thereby providing PDF output.
• And of course: many smaller feature upgrades and bug fixes.