SUNDIALS: SUite of Nonlinear and DIfferential/ALgebraic Equation Solvers
Release History
KINSOL :: sundialsTB

What’s New in SUNDIALS?

Changes in major release SUNDIALS v.4.0.0-dev

Version 4.0.0-dev is a first step toward the full 4.0.0 release which should be complete by end of 2018.  The 4.0.0 release will inlude a full redesign of our nonlinear solver interfaces allowing for encapsulation of the nonlinear solvers and ease in interfacing outside nonlinear solver packages.

  • New features and/or enhancements
    • Three fused vector operations and seven vector array operations have been added to the NVECTOR API. These optional operations are intended to increase data reuse in vector operations, reduce parallel communication on distributed memory systems, and lower the number of kernel launches on systems with accelerators. The new operations are N_VLinearCombination, N_VScaleAddMulti, N_VDotProdMulti, N_VLinearCombinationVectorArray, N_VScaleVectorArray, N_VConstVectorArray, N_VWrmsNormVectorArray, N_VWrmsNormMaskVectorArray, N_VScaleAddMultiVectorArray, and N_VLinearCombinationVectorArray. If any of these operations are defined as NULL in an NVECTOR implementation the NVECTOR interface will automatically call standard NVECTOR operations as necessary.   Details on the new operations can be found in the user guide Chapter on the NVECTOR API.
    • Several changes were made to the build system.
      • If MPI is enabled and MPI compiler wrappers are not set, the build system will check if  CMAKE_<language>_COMPILER can compile MPI programs before trying to locate and use an MPI installation. The native CMake FindMPI module is now used to locate an MPI installation.
      • The options for setting MPI compiler wrappers and the executable for running MPI programs have been updated to align with those in the native CMake FindMPI module. This included changing MPI_MPICC to MPI_C_COMPILER, MPI_MPICXX to MPI_CXX_COMPILER, combining MPI_MPIF77 and MPI_MPIF90 to MPI_Fortran_COMPILER, and changing MPI_RUN_COMMAND to MPIEXEC.
      • When a Fortran name-mangling scheme is needed (e.g., LAPACK_ENABLE is ON) the build system will infer the scheme from the Fortran compiler. If a Fortran compiler is not available or the inferred or default scheme needs to be overridden, the advanced options SUNDIALS_F77_FUNC_CASE and SUNDIALS_F77_FUNC_UNDERSCORES can be used to manually set the name-mangling scheme and bypass trying to infer the scheme.
      • Parts of the main CMakeLists.txt file were moved to new files in the src and example directories to make the CMake configuration file structure more modular.

Changes in major release SUNDIALS v.3.1.1

  • Fixed a potential memory leak in the SPGMR and SPFGMR linear solvers: if “Initialize” was called multiple times then the solver memory was reallocated (without being freed).
  • Fixed C++11 compiler errors/warnings about incompatible use of string literals.

  • Updated KLU SUNLinearSolver module to use a typedef for the precision-specific solve function to be used (to avoid compiler warnings).

  • Added missing typecasts for some (void*) pointers (again, to avoid compiler warnings).

  • Bugfix in sunmatrix_sparse.c where we had used ‘int’ instead of ‘sunindextype’ in one location.

  • Added missing #include <stdio.h> in NVECTOR and SUNMATRIX header files.

  • Fixed an indexing bug in the CUDA NVECTOR implementation of N_VWrmsNormMask and revised the RAJA NVECTOR implementation of N_VWrmsNormMask to work with mask arrays using values other than zero or one. Replaced doubles with realtypes in the RAJA vector test functions.

  • Fixed compilation issue with GCC 7.3.0 and Fortran programs that do not require a SUNMatrix or SUNLinearSolver module (e.g. iterative linear solvers, explicit methods in ARKode, functional iteration in CVODE, etc.).

  • In ARKode:

    • Fixed a minor bug in the ARKReInit routine, where a flag was incorrectly set to indicate that the problem had been resized (instead of just re-initialized).

    • Added missing prototype for ARKSpilsGetNumMTSetups.

  • In IDA and IDAS

    • Added missing prototypes for IDASpilsGetNumJTSetupEvals in IDA and IDAS.

  • In CVODE and CVODES:

    • Fixed a minor bug in the CVODE and CVODES cvSLdet routine, where a return was missing in the error check for three inconsistent roots.
  • In KINSOL:
    • Fixed a minor bug in KINPrintInfo where a case was missing for KIN_REPTD_SYSFUNC_ERR leading to an undefined info message.


Changes in major release SUNDIALS v.3.1.0


  • New features and/or enhancements
    • Added NVECTOR print functions that write vector data to a specified file (e.g., N_VPrintFile_Serial).
    • Added ‘make test’ and ‘make test_install’ options to the build system for testing SUNDIALS after building with ‘make’ and installing with ‘make install’ respectively.
    • Added “Changes in …” (latest version) to Intro. in all User Guides.

Changes in major release SUNDIALS v.3.0.0

  • New features and/or enhancements
    • New linear solver API and interfaces for all SUNDIALS packages and linear solvers.  The goal of the redesign of these interfaces was to provide more encapsulation and ease in interfacing custom linear solvers and interoperability with linear solver libraries.
      • Added generic SUNMATRIX module with three provided implementations: dense, banded, and sparse.  These implementations replicate previous SUNDIALS Dls and Sls matrix structures in a single object-oriented API.
      • Added example problems demonstrating use of generic SUNMATRIX modules.
      • Added generic SUNLINEARSOLVER module with eleven provided implementations: dense, banded, LAPACK dense, LAPACK band, KLU, SuperLU_MT, SPGMR, SPBCGS, SPTFQMR, SPFGMR, and PCG.  These implementations replicate previous SUNDIALS generic linear solvers in a single object-oriented API.
      • Added example problems demonstrating use of generic SUNLINEARSOLVER modules.
      • Expanded package-provided direct linear solver (Dls) interfaces and scaled, preconditioned, iterative linear solver (Spils) interfaces to utilize generic SUNMATRIX and SUNLINEARSOLVER objects.
      • Removed package-specific, linear solver-specific, solver modules (e.g. CVDENSE, KINBAND, IDAKLU, ARKSPGMR) since their functionality is entirely replicated by the generic Dls/Spils interfaces and SUNLINEARSOLVER/SUNMATRIX modules.  The exception is CVDIAG, a diagonal approximate Jacobian solver available to CVODE and CVODES.
      • Converted all SUNDIALS example problems to utilize new generic SUNMATRIX and SUNLINEARSOLVER objects, along with updated Dls and Spils linear solver interfaces.
      • Added Spils interface routines to ARKode, CVODE, CVODES, IDA and IDAS to allow specification of a user-provided “JTSetup” routine. This change supports users who wish to set up data structures for the user-provided Jacobian-times-vector (“JTimes”) routine, and where the cost of one JTSetup setup per Newton iteration can be amortized between multiple JTimes calls.
    • Two new NVECTOR modules added: for CUDA and RAJA support for GPU systems.  These vectors are supplied to provide very basic support for running on GPU architectures.  Users are advised that these vectors both move all data to the GPU device upon construction, and speedup will only be realized if the user also conducts the right-hand-side function evaluation on the device. In addition, these vectors assume the problem fits on one GPU. For further information about RAJA, users are referred to the web site,
    • Addition of sunindextype option for 32- or 64-bit integer data index types within all SUNDIALS structures.
      • Sunindextype can be int64_t or int32_t or long long int and int depending on machine support for portable types.
      • The Fortran interfaces continue to use long_int for indices, except for their sparse matrix interface that now uses the new sunindextype.
      • Includes interfaces to PETSc, hypre, SuperLU_MT, and KLU with either 64-bit or 32-bit capabilities depending how the user configures SUNDIALS.
    • Temporary vectors were removed from preconditioner setup and solve routines for all packages.  It is assumed that all necessary data for user-provided preconditioner operations will be allocated and stored in user-provided data structures.
    • The file include/sundials_fconfig.h was added.  This file contains SUNDIALS type information for use in Fortran programs. 
    • Added support for many xSDK-compliant build system keys.
      • The xSDK is a movement in scientific software to provide a foundation for the rapid and efficient production of high-quality, sustainable extreme-scale scientific applications. 
      • More information can be found at
    • Added functions SUNDIALSGetVersion and SUNDIALSGetVersionNumber to
      get SUNDIALS release version information at runtime.

    • To avoid potential namespace conflicts, the macros defining booleantype values TRUE and FALSE have been changed to SUNTRUE and SUNFALSE respectively.

    • In build system:

      • Added separate BLAS_ENABLE and BLAS_LIBRARIES CMake variables.
      • Additional error checking during CMake configuration.
      • Fixed minor CMake bugs.
      • Renamed CMake options to enable/disable examples for greater clarity and added option to enable/disable Fortran 77 examples:
        • Changed F90_ENABLE to EXAMPLES_ENABLE_F90.
        • Added EXAMPLES_ENABLE_F77 option.
    • Corrections and additions to all User Guides.
  • In ARKode:
    • Added comments to arkode_butcher.c regarding which methods should have coefficients accurate enough for use in quad precision.
    • Bug Fix: Fixed a bug in arkode_butcher.c in use of RCONST.
    • Bug Fix: Fixed a bug in in the arkInitialSetup utility routine in the order of operations when setting up and using mass matrices to ensure the mass matrix vector product is set up before the “msetup”
        routine is called.
    • Fixed ARKode printf-related compiler warnings when building SUNDIALS with extended precision.
    • In CVodeFree, now call lfree() unconditionally (if non-NULL).
  • In IDA/IDAS:
    • Bug Fix: Added missing prototype for IDASetMaxBacksIC in ida.h and idas.h.
  • In KINSOL:
    • Bug Fix: Corrected KINSOL fcmix name translation for FKIN_SPFGMR.

Changes in major release SUNDIALS v.2.7.0

  • Two new NVECTOR modules added: for Hypre ParVector and PETSC.
  • In vector API, added new required function, N_VGetVectorID.
  • Upgrades to sparse solver interfaces; now support CSR matrix type with KLU solver.
  • In all packages, example codes were changed from using NV_DATA macro to using N_VGetArrayPointer_* when using the native vectors shipped with SUNDIALS
  • In all packages, fixed memory leak in banded preconditioner interface.
  • Fixed some examples w.r.t. switch to new macro/function names SUNRexp etc.
  • Various minor fixes to installation-related files.
  • Corrected name N_VCloneEmptyVectorArray to N_VCloneVectorArrayEmpty in all documentation files.
  • Updated all packages to return integers from linear solver and preconditioner ‘free’ functions.
  • Removed Matlab interface from distribution as it has not been updated since 2009.  We expect to update this interface soon.
  • In FKINSOL, FCVODE, and FIDA, added missing Fortran interface routines so that users can supply the sparse Jacobian routine.
  • Minor corrections and additions to all User Guides, including removal of references to specific NVECTOR names in usage skeletons.
  • Additional example programs added throughout.
  • In CVODE
    • in FCVODE, fixed argument order bugs in FCVKLU and FCVSUPERLUMT linear solver interfaces.
    • changed each **FreeB() to type int; added return(0) to each.  
    • in interpolation routines for backward problems, added logic to bypass sensitivity interpolation if input sensitivity argument is NULL.
    • updated linear and mass matrix solvers so that ‘free’ routines return integer instead of void; updated documentation accordingly.
    • fixed initialization of linear solver performance counters.
    • method and embedding for Billington and TRBDF2 explicit Runge-Kutta methods were swapped.
    • fix for user specification of absolute tolerance array along with vector Resize() functionality.
    • fix for user-supplied Butcher tables without embeddings (if fixed time steps or manual adaptivity are employed).
    • multiple documentation updates.
    • added missing ARKSpilsGetNumMtimesEvals() function. 
    • implicit predictor algorithms were updated: methods 2 and 3 were improved, a new predictor approach was added, and the default choice was modified.
    • revised handling of integer codes for specifying built-in Butcher tables: a global numbering system is still used, but methods now have #defined names to simplify the user interface.
    • maximum number of Butcher table stages was increased from 8 to 15 to accommodate very high order methods, and an 8th-order adaptive ERK method was added.
    • added support for the explicit and implicit methods in an additive Runge-Kutta method to utilize different stage times, solution and embedding coefficients, to support new SSP-ARK methods.
    • extended FARKODE interface to include a routine to set scalar/array-valued residual tolerances, to support Fortran applications with non-identity mass-matrices.
  • In IDA
    • corrected example idaFoodWeb_bnd.c in PrintOutput (wrong component printed).
    • added optional input function IDASetMaxBacksIC to limit number of linesearch backtrack operations in IDACalcIC.  User guides amended accordingly.
  • In IDAS
    • added optional input function IDASetMaxBacksIC to limit number of linesearch backtrack operations in IDACalcIC.  User guides amended accordingly.
    • changed each **FreeB() to type int; added return(0) to each.  
    • in interpolation routines for backward problems, added logic to bypass sensitivity interpolation if input sensitivity argument is NULL.
    • minor bug fix in Picard iteration.
    • minor bug fix in line search to prevent infinite loop when beta condition fails and lambda is below minimum size.

Changes in minor release SUNDIALS v.2.6.2

  • In IDAS, added missing backward problem support functions: IDALapackDenseB, IDALapackDenseFreeB, IDALapackBandB, IDALapackBandFreeB
  • In KINSOL and ARKode, updated Anderson acceleration implementation with QR updating.
  • Updated BiCGStab solver to remove redundant dot product call.
  • Minor corrections and additions to all User Guides.
  • In CVODES and IDAS header files, corrected documentation of backward integration functions, especially the ‘which’ argument.
  • In CVODES, added DVKLUB prototype and corrected CVSuperLUMTB prototype.
  • In IDAS, made SuperLUMT call for backward problem consistent with CVODES.
  • In CVODES and IDAS, added ReInit and SetOrdering wrappers for backward problems. Fixed potential memory leak in KLU ReInit functions in all solvers.
  • In CVODE, IDA, and ARKode, fixed Fortran interfaces to enable calls to *GetErrWeights, *GetEstLocalErrors, and *GetDky within a time step. In ARKode, fixed a bug in one Butcher table.
  • In ARKode, fixed error in arkDoErrorTest in recovery after failure.
  • In IDAS, fixed for-loop bugs in IDAAckpntAllocVectors Various minor fixes to installation-related files.

Summary of changes in minor release SUNDIALS v.2.6.1

  • Fixed loop limit bug in SlsAddMat function.
  • In all six solver interfaces to KLU and SuperLUMT, added #include lines, and removed redundant KLU structure allocations.
  • Numerous minor documentation improvements
  • Minor bug fixes in ARKode

Summary of major changes in SUNDIALS v.2.6.0

  • Addition of ARKode package of explicit, implicit, and additive Runge-Kutta methods for ODES. This package API is close to CVODE so switching between the two should be straightforward. Thanks go to Daniel Reynolds for the addition of this package.
  • Addition of support for two sparse direct solver packages when using the serial vector structure, KLU and SuperLU_MT. exploits highly sparse systems. SuperLU_MT supports multithreading in the factorization.
  • Addition of openMP and PThreads vector kernels.
  • Addition of fixed point and Picard iterative solvers within KINSOL. These are both optionally accelerated with Anderson acceleration.
  • Addition of FGMRES support for KINSOL.
  • Removal of autotools configuration support. We now exclusively use CMake.
  • Numerous bug fixes throughout.

    Summary of major changes in v2.5.0?

    • Changes to user interface
      • Problem size and related integers (bandwidth parameters etc.) all have type long int, except in BLAS and LAPACK routines. Function NewIntArray is replaced by a pair NewIntArray/NewLintArray, for int and long int arrays, respectively.

      Summary of major changes in v2.4.0?

      • New features
        • new linear solver module, based on Blas and Lapack for both dense and banded matrices.
      • Changes to user interface
        • reorganization of all linear solver modules into two families (besides the existing family of scaled preconditioned iterative linear solvers, the direct solvers, including the new Lapack-based ones, were also organized into a direct family).
      • Changes related to the build system
        • provide CMake-based build option, in addition to that based on autotools.

        Summary of major changes in v2.3.0?

        • Changes to the user interface
          • modified the functions in the generic dense linear solver (sundials_dense and sundials_smalldense) to work for rectangular m by n matrices (m ≤ n).
          • renamed the factorization and solution functions in the generic dense linear solver to DenseGETRF/denGETRF and DenseGETRS/denGETRS, respectively.
          • renamed the factorization and solution functions in the generic band linear solver to BandGBTRF and BandGBTRS, respectively.
        • Changes related to the build system
          • rearranged the entire SUNDIALS source tree
          • all exported header files are now installed in separate subdirectories of the installtion include directory
          • header files are included now by specifying the relative path (e.g. #include <sundials/sundials_types.h>)

          Summary of major changes in v2.2.0?

          • New features
            • added SPBCG (scaled preconditioned Bi-CGStab) linear solver module
            • added SPTFQMR (scaled preconditioned TFQMR) linear solver module
          • Changes related to the build system
            • updated configure script and Makefiles for Fortran examples to avoid C++ compiler errors (now use CC and MPICC to link only if necessary)
            • SUNDIALS shared header files are installed under a sundials subdirectory of the installation include directory
            • the shared object files are now linked into each SUNDIALS library rather than into a separate libsundials_shared library
          • Changes to the user interface
            • added prefix sundials_ to all shared header files

            Summary of major changes in v2.1.1?

            • Changes to the generic NVECTOR module
              • N_VCloneEmpty was added to the global vector operations table

            Summary of major changes in v2.0.2?

            • Changes related to the build system
              • fixed autoconf-related bug to allow configuration with the PGI Fortran compiler
              • modified to use customized detection of the Fortran name mangling scheme (autoconf’s AC_F77_WRAPPERS routine is problematic on some platforms)

              Summary of major changes in v2.0.1?

              • Changes related to the build system
                • changed order of compiler directives in header files to avoid compilation errors when using a C++ compiler.
                • changed method of generating sundials_config.h to avoid potential warnings of redefinition of preprocessor symbols.

                Summary of major changes in v2.0?

                • Changes to the generic NVECTOR module
                  • removed machEnv, redefined table of vector operations (now contained in the N_Vector structure itself).
                  • all SUNDIALS functions create new N_Vector variables through cloning, using an N_Vector passed by the user as a template.
                  • a particular NVECTOR implementation is supposed to provide user-callable constructor and destructor functions.
                  • removed from structure of vector operations the following functions: N_VNew, N_VNew_S, N_VFree, N_VFree_S, N_VMake, N_VDispose, N_VGetData, N_VSetData, N_VConstrProdPos, and N_VOneMask.
                  • added in structure of vector operations the following functions: N_VClone, N_VDestroy, N_VSpace, N_VGetArrayPointer, N_VSetArrayPointer, and N_VWrmsNormMask.
                  • Note that nvec_ser and nvec_par are now separate modules outside the shared SUNDIALS module.
                • Changes to the generic linear solvers
                  • in SPGMR, added a dummy N_Vector argument to be used as a template for cloning.
                  • in SPGMR, removed N (problem dimension) from argument list of SpgmrMalloc.
                  • iterative.{c,h} replace iterativ.{c,h}
                  • modified constant names in iterative.h (preconditioner types are prefixed with ‘PREC_’).
                  • changed numerical values for MODIFIED_GS (from 0 to 1) and CLASSICAL_GS (from 1 to 2).
                • Changes to sundialsmath submodule
                  • replaced internal routine for estimation of unit roundoff with definition of unit roundoff from float.h
                  • modified functions to call appropriate math routines given the precision level specified by the user.
                • Changes to sundialstypes submodule
                  • removed type ‘integertype’.
                  • added definitions for ‘BIG_REAL’, ‘SMALL_REAL’, and ‘UNIT_ROUNDOFF’ using values from float.h based on the precision.
                  • changed definition of macro RCONST to depend on precision.

                cvode release history


                cvodes release history


                arkode release history


                ida release history


                idas release history


                kinsol release history

                TOP :: CVODE :: CVODES :: ARKODE ::  IDA :: IDAS
                KINSOL :: sundialsTB


                sundialsTB is no longer distributed as of sundials v. 2.7.0 as it has not been updated in many years.

                What’s new in v2.5.0?

                • Bug fixes
                  • fixed lines setting etachoice in kimOpts.c
                  • in cvm.c and idm.c, fixed size of rootsfound array; added lines to free rootsfound and ckpnt arrays when done using each
                • What’s new in v2.4.0?
                • New Features
                  • the Matlab interface to IDAS was extended to provide sensitivity analysis capabilities.
                • Changes to user interface
                  • the API for adjoint sensitivity analysis (cvodes and idas) was modified to support simultaneous integration of multiple backward problems.

                What’s new in v2.3.0?

                • New features
                  • added Matlab interface to IDA (named idas)
                  • on platforms which support configure scripts, installtion of sundialsTB can now be enabled while configuring SUNDIALS and installed through make and make install (provided a working MEX compiler is found).
                • Bug fixes
                  • the installation script install_STB.m was modified to increase robustness on various platforms (related to path and file names).
                • Changes to user interface
                  • (cvodes) for improved legibility, some of the keys for forward sensitivity optional inputs were renamed.
                  • (cvodes) removed xaxis type option for the internal monitoring function CVodeMonitor.

                What’s new in v2.2.0?

                • New features
                  • modified installation procedure to use a Matlab script
                  • added sample Matlab startup file
                  • (cvodes) expanded CVodeMonitor
                  • (kinsol) added interface to KINSOL’s performance monitoring function (‘Verbose’ option to KINSetOptions)
                • Bug fixes
                  • (cvodes) fixed bug in interface to quadrature integration which was causing a segmentation violation when monitoring was turned on.
                • Changes to user interface
                  • updated to reflect changes to the SUNDIALS libraries in v.2.2.0
                  • (cvodes) changed the interface for sensitivity analysis (both forward and adjoint) to follow more closely the CVODES calling sequence
                  • (cvodes) optional inputs for forward sensitivity analysis are now provided through a separate function, CVodeSensSetOptions
                  • removed NVM mex interface