Date: 2026-03-01T05:24:32+00:00

Actual source code: petscksp.h

      1: /*
      2:    Defines the interface functions for the Krylov subspace accelerators.
      3: */
      4: #pragma once

      6: #include <petscpc.h>

      8: /* SUBMANSEC = KSP */

     10: PETSC_EXTERN PetscErrorCode KSPInitializePackage(void);
     11: PETSC_EXTERN PetscErrorCode KSPFinalizePackage(void);

     13: /*S
     14:    KSP - Abstract PETSc object that manages the linear solves in PETSc (even those such as direct factorization-based solvers that
     15:          do not use Krylov accelerators).

     17:    Level: beginner

     19:    Notes:
     20:    When a direct solver is used, but no Krylov solver is used, the `KSP` object is still used but with a
     21:    `KSPType` of `KSPPREONLY` (or equivalently `KSPNONE`), meaning that only application of the preconditioner is used as the linear solver.

     23:    Use `KSPSetType()` or the options database key `-ksp_type` to set the specific Krylov solver algorithm to use with a given `KSP` object

     25:    The `PC` object is used to control preconditioners in PETSc.

     27:   `KSP` can also be used to solve some least squares problems (over or under-determined linear systems), using, for example, `KSPLSQR`, see `PETSCREGRESSORLINEAR`
     28:   for additional methods that can be used to solve least squares problems and other linear regressions).

     30: .seealso: [](doc_linsolve), [](ch_ksp), `KSPCreate()`, `KSPSetType()`, `KSPType`, `SNES`, `TS`, `PC`, `KSP`, `KSPDestroy()`, `KSPCG`, `KSPGMRES`
     31: S*/
     32: typedef struct _p_KSP *KSP;

     34: /*J
     35:    KSPType - String with the name of a PETSc Krylov method. These are all the Krylov solvers that PETSc provides.

     37:    Level: beginner

     39: .seealso: [](doc_linsolve), [](ch_ksp), `KSPSetType()`, `KSP`, `KSPRegister()`, `KSPCreate()`, `KSPSetFromOptions()`
     40: J*/
     41: typedef const char *KSPType;
     42: #define KSPRICHARDSON "richardson"
     43: #define KSPCHEBYSHEV  "chebyshev"
     44: #define KSPCG         "cg"
     45: #define KSPGROPPCG    "groppcg"
     46: #define KSPPIPECG     "pipecg"
     47: #define KSPPIPECGRR   "pipecgrr"
     48: #define KSPPIPELCG    "pipelcg"
     49: #define KSPPIPEPRCG   "pipeprcg"
     50: #define KSPPIPECG2    "pipecg2"
     51: #define KSPCGNE       "cgne"
     52: #define KSPNASH       "nash"
     53: #define KSPSTCG       "stcg"
     54: #define KSPGLTR       "gltr"
     55: #define KSPCGNASH     PETSC_DEPRECATED_MACRO(3, 11, 0, "KSPNASH", ) "nash"
     56: #define KSPCGSTCG     PETSC_DEPRECATED_MACRO(3, 11, 0, "KSPSTCG", ) "stcg"
     57: #define KSPCGGLTR     PETSC_DEPRECATED_MACRO(3, 11, 0, "KSPSGLTR", ) "gltr"
     58: #define KSPFCG        "fcg"
     59: #define KSPPIPEFCG    "pipefcg"
     60: #define KSPGMRES      "gmres"
     61: #define KSPPIPEFGMRES "pipefgmres"
     62: #define KSPFGMRES     "fgmres"
     63: #define KSPLGMRES     "lgmres"
     64: #define KSPDGMRES     "dgmres"
     65: #define KSPPGMRES     "pgmres"
     66: #define KSPTCQMR      "tcqmr"
     67: #define KSPBCGS       "bcgs"
     68: #define KSPIBCGS      "ibcgs"
     69: #define KSPQMRCGS     "qmrcgs"
     70: #define KSPFBCGS      "fbcgs"
     71: #define KSPFBCGSR     "fbcgsr"
     72: #define KSPBCGSL      "bcgsl"
     73: #define KSPPIPEBCGS   "pipebcgs"
     74: #define KSPCGS        "cgs"
     75: #define KSPTFQMR      "tfqmr"
     76: #define KSPCR         "cr"
     77: #define KSPPIPECR     "pipecr"
     78: #define KSPLSQR       "lsqr"
     79: #define KSPPREONLY    "preonly"
     80: #define KSPNONE       "none"
     81: #define KSPQCG        "qcg"
     82: #define KSPBICG       "bicg"
     83: #define KSPMINRES     "minres"
     84: #define KSPSYMMLQ     "symmlq"
     85: #define KSPLCD        "lcd"
     86: #define KSPPYTHON     "python"
     87: #define KSPGCR        "gcr"
     88: #define KSPPIPEGCR    "pipegcr"
     89: #define KSPTSIRM      "tsirm"
     90: #define KSPCGLS       "cgls"
     91: #define KSPFETIDP     "fetidp"
     92: #define KSPHPDDM      "hpddm"

     94: /* Logging support */
     95: PETSC_EXTERN PetscClassId KSP_CLASSID;
     96: PETSC_EXTERN PetscClassId KSPGUESS_CLASSID;
     97: PETSC_EXTERN PetscClassId DMKSP_CLASSID;

     99: PETSC_EXTERN PetscErrorCode KSPCreate(MPI_Comm, KSP *);
    100: PETSC_EXTERN PetscErrorCode KSPSetType(KSP, KSPType);
    101: PETSC_EXTERN PetscErrorCode KSPGetType(KSP, KSPType *);
    102: PETSC_EXTERN PetscErrorCode KSPSetUp(KSP);
    103: PETSC_EXTERN PetscErrorCode KSPSetUpOnBlocks(KSP);
    104: PETSC_EXTERN PetscErrorCode KSPSolve(KSP, Vec, Vec);
    105: PETSC_EXTERN PetscErrorCode KSPSolveTranspose(KSP, Vec, Vec);
    106: PETSC_EXTERN PetscErrorCode KSPSetUseExplicitTranspose(KSP, PetscBool);
    107: PETSC_EXTERN PetscErrorCode KSPMatSolve(KSP, Mat, Mat);
    108: PETSC_EXTERN PetscErrorCode KSPMatSolveTranspose(KSP, Mat, Mat);
    109: PETSC_EXTERN PetscErrorCode KSPSetMatSolveBatchSize(KSP, PetscInt);
    110: PETSC_DEPRECATED_FUNCTION(3, 15, 0, "KSPSetMatSolveBatchSize()", ) static inline PetscErrorCode KSPSetMatSolveBlockSize(KSP ksp, PetscInt n)
    111: {
    112:   return KSPSetMatSolveBatchSize(ksp, n);
    113: }
    114: PETSC_EXTERN PetscErrorCode KSPGetMatSolveBatchSize(KSP, PetscInt *);
    115: PETSC_DEPRECATED_FUNCTION(3, 15, 0, "KSPGetMatSolveBatchSize()", ) static inline PetscErrorCode KSPGetMatSolveBlockSize(KSP ksp, PetscInt *n)
    116: {
    117:   return KSPGetMatSolveBatchSize(ksp, n);
    118: }
    119: PETSC_EXTERN PetscErrorCode KSPReset(KSP);
    120: PETSC_EXTERN PetscErrorCode KSPResetViewers(KSP);
    121: PETSC_EXTERN PetscErrorCode KSPDestroy(KSP *);
    122: PETSC_EXTERN PetscErrorCode KSPSetReusePreconditioner(KSP, PetscBool);
    123: PETSC_EXTERN PetscErrorCode KSPGetReusePreconditioner(KSP, PetscBool *);
    124: PETSC_EXTERN PetscErrorCode KSPSetSkipPCSetFromOptions(KSP, PetscBool);
    125: PETSC_EXTERN PetscErrorCode KSPCheckSolve(KSP, PC, Vec);

    127: PETSC_EXTERN PetscFunctionList KSPList;
    128: PETSC_EXTERN PetscFunctionList KSPGuessList;
    129: PETSC_EXTERN PetscFunctionList KSPMonitorList;
    130: PETSC_EXTERN PetscFunctionList KSPMonitorCreateList;
    131: PETSC_EXTERN PetscFunctionList KSPMonitorDestroyList;
    132: PETSC_EXTERN PetscErrorCode    KSPRegister(const char[], PetscErrorCode (*)(KSP));

    134: /*S
    135:   KSPMonitorRegisterFn - A function prototype for functions provided to `KSPMonitorRegister()`

    137:   Calling Sequence:
    138: + ksp   - iterative solver obtained from `KSPCreate()`
    139: . it    - iteration number
    140: . rnorm - (estimated) 2-norm of (preconditioned) residual
    141: - ctx   - `PetscViewerAndFormat` object

    143:   Level: beginner

    145:   Note:
    146:   This is a `KSPMonitorFn` specialized for a context of `PetscViewerAndFormat`

    148: .seealso: [](ch_snes), `KSP`, `KSPMonitorSet()`, `KSPMonitorRegister()`, `KSPMonitorFn`, `KSPMonitorRegisterCreateFn`, `KSPMonitorRegisterDestroyFn`
    149: S*/
    150: PETSC_EXTERN_TYPEDEF typedef PetscErrorCode KSPMonitorRegisterFn(KSP ksp, PetscInt it, PetscReal rnorm, PetscViewerAndFormat *ctx);

    152: /*S
    153:   KSPMonitorRegisterCreateFn - A function prototype for functions that do the creation when provided to `KSPMonitorRegister()`

    155:   Calling Sequence:
    156: + viewer - the viewer to be used with the `KSPMonitorRegisterFn`
    157: . format - the format of the viewer
    158: . ctx    - a context for the monitor
    159: - result - a `PetscViewerAndFormat` object

    161:   Level: beginner

    163: .seealso: [](ch_snes), `KSPMonitorRegisterFn`, `KSP`, `KSPMonitorSet()`, `KSPMonitorRegister()`, `KSPMonitorFn`, `KSPMonitorRegisterDestroyFn`
    164: S*/
    165: PETSC_EXTERN_TYPEDEF typedef PetscErrorCode KSPMonitorRegisterCreateFn(PetscViewer viewer, PetscViewerFormat format, void *ctx, PetscViewerAndFormat **result);

    167: /*S
    168:   KSPMonitorRegisterDestroyFn - A function prototype for functions that do the after use destruction when provided to `KSPMonitorRegister()`

    170:   Calling Sequence:
    171: . vf - a `PetscViewerAndFormat` object to be destroyed, including any context

    173:   Level: beginner

    175: .seealso: [](ch_snes), `KSPMonitorRegisterFn`, `KSP`, `KSPMonitorSet()`, `KSPMonitorRegister()`, `KSPMonitorFn`, `KSPMonitorRegisterCreateFn`
    176: S*/
    177: PETSC_EXTERN_TYPEDEF typedef PetscErrorCode KSPMonitorRegisterDestroyFn(PetscViewerAndFormat **result);

    179: PETSC_EXTERN PetscErrorCode KSPMonitorRegister(const char[], PetscViewerType, PetscViewerFormat, KSPMonitorRegisterFn *, KSPMonitorRegisterCreateFn *, KSPMonitorRegisterDestroyFn *);

    181: PETSC_EXTERN PetscErrorCode KSPSetPCSide(KSP, PCSide);
    182: PETSC_EXTERN PetscErrorCode KSPGetPCSide(KSP, PCSide *);
    183: PETSC_EXTERN PetscErrorCode KSPSetTolerances(KSP, PetscReal, PetscReal, PetscReal, PetscInt);
    184: PETSC_EXTERN PetscErrorCode KSPGetTolerances(KSP, PetscReal *, PetscReal *, PetscReal *, PetscInt *);
    185: PETSC_EXTERN PetscErrorCode KSPSetMinimumIterations(KSP, PetscInt);
    186: PETSC_EXTERN PetscErrorCode KSPGetMinimumIterations(KSP, PetscInt *);
    187: PETSC_EXTERN PetscErrorCode KSPSetInitialGuessNonzero(KSP, PetscBool);
    188: PETSC_EXTERN PetscErrorCode KSPGetInitialGuessNonzero(KSP, PetscBool *);
    189: PETSC_EXTERN PetscErrorCode KSPSetErrorIfNotConverged(KSP, PetscBool);
    190: PETSC_EXTERN PetscErrorCode KSPGetErrorIfNotConverged(KSP, PetscBool *);
    191: PETSC_EXTERN PetscErrorCode KSPSetComputeEigenvalues(KSP, PetscBool);
    192: PETSC_EXTERN PetscErrorCode KSPSetComputeRitz(KSP, PetscBool);
    193: PETSC_EXTERN PetscErrorCode KSPGetComputeEigenvalues(KSP, PetscBool *);
    194: PETSC_EXTERN PetscErrorCode KSPSetComputeSingularValues(KSP, PetscBool);
    195: PETSC_EXTERN PetscErrorCode KSPGetComputeSingularValues(KSP, PetscBool *);
    196: PETSC_EXTERN PetscErrorCode KSPGetRhs(KSP, Vec *);
    197: PETSC_EXTERN PetscErrorCode KSPGetSolution(KSP, Vec *);
    198: PETSC_EXTERN PetscErrorCode KSPGetResidualNorm(KSP, PetscReal *);
    199: PETSC_EXTERN PetscErrorCode KSPGetIterationNumber(KSP, PetscInt *);
    200: PETSC_EXTERN PetscErrorCode KSPGetTotalIterations(KSP, PetscInt *);
    201: PETSC_EXTERN PetscErrorCode KSPCreateVecs(KSP, PetscInt, Vec **, PetscInt, Vec **);
    202: PETSC_DEPRECATED_FUNCTION(3, 6, 0, "KSPCreateVecs()", ) static inline PetscErrorCode KSPGetVecs(KSP ksp, PetscInt n, Vec **x, PetscInt m, Vec **y)
    203: {
    204:   return KSPCreateVecs(ksp, n, x, m, y);
    205: }

    207: /*S
    208:   KSPPSolveFn - A function prototype for functions provided to `KSPSetPreSolve()` and `KSPSetPostSolve()`

    210:   Calling Sequence:
    211: + ksp - the `KSP` context
    212: . rhs - the right-hand side vector
    213: . x   - the solution vector
    214: - ctx - optional context that was provided with `KSPSetPreSolve()` or `KSPSetPostSolve()`

    216:   Level: intermediate

    218: .seealso: [](ch_snes), `KSP`, `KSPSetPreSolve()`, `KSPSetPostSolve()`, `PCShellPSolveFn`
    219: S*/
    220: PETSC_EXTERN_TYPEDEF typedef PetscErrorCode KSPPSolveFn(KSP ksp, Vec rhs, Vec x, void *ctx);

    222: PETSC_EXTERN PetscErrorCode KSPSetPreSolve(KSP, KSPPSolveFn *, void *);
    223: PETSC_EXTERN PetscErrorCode KSPSetPostSolve(KSP, KSPPSolveFn *, void *);

    225: PETSC_EXTERN PetscErrorCode KSPSetPC(KSP, PC);
    226: PETSC_EXTERN PetscErrorCode KSPGetPC(KSP, PC *);
    227: PETSC_EXTERN PetscErrorCode KSPSetNestLevel(KSP, PetscInt);
    228: PETSC_EXTERN PetscErrorCode KSPGetNestLevel(KSP, PetscInt *);

    230: /*S
    231:   KSPMonitorFn - A function prototype for functions provided to `KSPMonitorSet()`

    233:   Calling Sequence:
    234: + ksp   - iterative solver obtained from `KSPCreate()`
    235: . it    - iteration number
    236: . rnorm - (estimated) 2-norm of (preconditioned) residual
    237: - ctx   - optional monitoring context, as provided with `KSPMonitorSet()`

    239:   Level: beginner

    241: .seealso: [](ch_snes), `KSP`, `KSPMonitorSet()`
    242: S*/
    243: PETSC_EXTERN_TYPEDEF typedef PetscErrorCode KSPMonitorFn(KSP ksp, PetscInt it, PetscReal rnorm, void *ctx);

    245: PETSC_EXTERN PetscErrorCode KSPMonitor(KSP, PetscInt, PetscReal);
    246: PETSC_EXTERN PetscErrorCode KSPMonitorSet(KSP, KSPMonitorFn *, void *, PetscCtxDestroyFn *);
    247: PETSC_EXTERN PetscErrorCode KSPMonitorCancel(KSP);
    248: PETSC_EXTERN PetscErrorCode KSPGetMonitorContext(KSP, void *);
    249: PETSC_EXTERN PetscErrorCode KSPGetResidualHistory(KSP, const PetscReal *[], PetscInt *);
    250: PETSC_EXTERN PetscErrorCode KSPSetResidualHistory(KSP, PetscReal[], PetscCount, PetscBool);
    251: PETSC_EXTERN PetscErrorCode KSPGetErrorHistory(KSP, const PetscReal *[], PetscInt *);
    252: PETSC_EXTERN PetscErrorCode KSPSetErrorHistory(KSP, PetscReal[], PetscCount, PetscBool);

    254: PETSC_EXTERN PetscErrorCode KSPBuildSolutionDefault(KSP, Vec, Vec *);
    255: PETSC_EXTERN PetscErrorCode KSPBuildResidualDefault(KSP, Vec, Vec, Vec *);
    256: PETSC_EXTERN PetscErrorCode KSPDestroyDefault(KSP);
    257: PETSC_EXTERN PetscErrorCode KSPSetWorkVecs(KSP, PetscInt);

    259: PETSC_EXTERN PetscErrorCode PCKSPGetKSP(PC, KSP *);
    260: PETSC_EXTERN PetscErrorCode PCKSPSetKSP(PC, KSP);
    261: PETSC_EXTERN PetscErrorCode PCBJacobiGetSubKSP(PC, PetscInt *, PetscInt *, KSP *[]);
    262: PETSC_EXTERN PetscErrorCode PCASMGetSubKSP(PC, PetscInt *, PetscInt *, KSP *[]);
    263: PETSC_EXTERN PetscErrorCode PCGASMGetSubKSP(PC, PetscInt *, PetscInt *, KSP *[]);
    264: PETSC_EXTERN PetscErrorCode PCPatchGetSubKSP(PC, PetscInt *, KSP *[]);
    265: PETSC_EXTERN PetscErrorCode PCFieldSplitGetSubKSP(PC, PetscInt *, KSP *[]);
    266: PETSC_EXTERN PetscErrorCode PCFieldSplitSchurGetSubKSP(PC, PetscInt *, KSP *[]);
    267: PETSC_EXTERN PetscErrorCode PCMGGetSmoother(PC, PetscInt, KSP *);
    268: PETSC_EXTERN PetscErrorCode PCMGGetSmootherDown(PC, PetscInt, KSP *);
    269: PETSC_EXTERN PetscErrorCode PCMGGetSmootherUp(PC, PetscInt, KSP *);
    270: PETSC_EXTERN PetscErrorCode PCMGGetCoarseSolve(PC, KSP *);
    271: PETSC_EXTERN PetscErrorCode PCGalerkinGetKSP(PC, KSP *);
    272: PETSC_EXTERN PetscErrorCode PCDeflationGetCoarseKSP(PC, KSP *);

    274: /*S
    275:   PCMGCoarseSpaceConstructorFn - A function prototype for functions registered with `PCMGRegisterCoarseSpaceConstructor()`

    277:   Calling Sequence:
    278: + pc        - The `PC` object
    279: . l         - The multigrid level, 0 is the coarse level
    280: . dm        - The `DM` for this level
    281: . smooth    - The level smoother
    282: . Nc        - The size of the coarse space
    283: . initGuess - Basis for an initial guess for the space
    284: - coarseSp  - A basis for the computed coarse space

    286:   Level: beginner

    288: .seealso: [](ch_ksp), `PCMGRegisterCoarseSpaceConstructor()`, `PCMGGetCoarseSpaceConstructor()`
    289: S*/
    290: PETSC_EXTERN_TYPEDEF typedef PetscErrorCode PCMGCoarseSpaceConstructorFn(PC pc, PetscInt l, DM dm, KSP smooth, PetscInt Nc, Mat initGuess, Mat *coarseSp);

    292: PETSC_EXTERN PetscFunctionList PCMGCoarseList;
    293: PETSC_EXTERN PetscErrorCode    PCMGRegisterCoarseSpaceConstructor(const char[], PCMGCoarseSpaceConstructorFn *);
    294: PETSC_EXTERN PetscErrorCode    PCMGGetCoarseSpaceConstructor(const char[], PCMGCoarseSpaceConstructorFn **);

    296: PETSC_EXTERN PetscErrorCode KSPBuildSolution(KSP, Vec, Vec *);
    297: PETSC_EXTERN PetscErrorCode KSPBuildResidual(KSP, Vec, Vec, Vec *);

    299: /*E
    300:   KSPChebyshevKind - Which kind of Chebyshev polynomial to use with `KSPCHEBYSHEV`

    302:   Values:
    303: + `KSP_CHEBYSHEV_FIRST`      - "classic" first-kind Chebyshev polynomial
    304: . `KSP_CHEBYSHEV_FOURTH`     - fourth-kind Chebyshev polynomial
    305: - `KSP_CHEBYSHEV_OPT_FOURTH` - optimized fourth-kind Chebyshev polynomial

    307:   Level: intermediate

    309: .seealso: [](ch_ksp), `KSPCHEBYSHEV`, `KSPChebyshevSetKind()`, `KSPChebyshevGetKind()`
    310: E*/
    311: typedef enum {
    312:   KSP_CHEBYSHEV_FIRST,
    313:   KSP_CHEBYSHEV_FOURTH,
    314:   KSP_CHEBYSHEV_OPT_FOURTH
    315: } KSPChebyshevKind;

    317: PETSC_EXTERN PetscErrorCode KSPRichardsonSetScale(KSP, PetscReal);
    318: PETSC_EXTERN PetscErrorCode KSPRichardsonSetSelfScale(KSP, PetscBool);
    319: PETSC_EXTERN PetscErrorCode KSPChebyshevSetEigenvalues(KSP, PetscReal, PetscReal);
    320: PETSC_EXTERN PetscErrorCode KSPChebyshevEstEigSet(KSP, PetscReal, PetscReal, PetscReal, PetscReal);
    321: PETSC_EXTERN PetscErrorCode KSPChebyshevEstEigSetUseNoisy(KSP, PetscBool);
    322: PETSC_EXTERN PetscErrorCode KSPChebyshevSetKind(KSP, KSPChebyshevKind);
    323: PETSC_EXTERN PetscErrorCode KSPChebyshevGetKind(KSP, KSPChebyshevKind *);
    324: PETSC_EXTERN PetscErrorCode KSPChebyshevEstEigGetKSP(KSP, KSP *);
    325: PETSC_EXTERN PetscErrorCode KSPComputeExtremeSingularValues(KSP, PetscReal *, PetscReal *);
    326: PETSC_EXTERN PetscErrorCode KSPComputeEigenvalues(KSP, PetscInt, PetscReal[], PetscReal[], PetscInt *);
    327: PETSC_EXTERN PetscErrorCode KSPComputeEigenvaluesExplicitly(KSP, PetscInt, PetscReal[], PetscReal[]);
    328: PETSC_EXTERN PetscErrorCode KSPComputeRitz(KSP, PetscBool, PetscBool, PetscInt *, Vec[], PetscReal[], PetscReal[]);

    330: /*E

    332:   KSPFCDTruncationType - Define how stored directions are used to orthogonalize in flexible conjugate directions (FCD) methods

    334:   Values:
    335: + `KSP_FCD_TRUNC_TYPE_STANDARD` - uses all (up to mmax) stored directions
    336: - `KSP_FCD_TRUNC_TYPE_NOTAY`    - uses the last max(1,mod(i,mmax)) stored directions at iteration i=0,1..

    338:    Level: intermediate

    340: .seealso: [](ch_ksp), `KSP`, `KSPFCG`, `KSPPIPEFCG`, `KSPPIPEGCR`, `KSPFCGSetTruncationType()`, `KSPFCGGetTruncationType()`
    341: E*/
    342: typedef enum {
    343:   KSP_FCD_TRUNC_TYPE_STANDARD,
    344:   KSP_FCD_TRUNC_TYPE_NOTAY
    345: } KSPFCDTruncationType;
    346: PETSC_EXTERN const char *const KSPFCDTruncationTypes[];

    348: PETSC_EXTERN PetscErrorCode KSPFCGSetMmax(KSP, PetscInt);
    349: PETSC_EXTERN PetscErrorCode KSPFCGGetMmax(KSP, PetscInt *);
    350: PETSC_EXTERN PetscErrorCode KSPFCGSetNprealloc(KSP, PetscInt);
    351: PETSC_EXTERN PetscErrorCode KSPFCGGetNprealloc(KSP, PetscInt *);
    352: PETSC_EXTERN PetscErrorCode KSPFCGSetTruncationType(KSP, KSPFCDTruncationType);
    353: PETSC_EXTERN PetscErrorCode KSPFCGGetTruncationType(KSP, KSPFCDTruncationType *);

    355: PETSC_EXTERN PetscErrorCode KSPPIPEFCGSetMmax(KSP, PetscInt);
    356: PETSC_EXTERN PetscErrorCode KSPPIPEFCGGetMmax(KSP, PetscInt *);
    357: PETSC_EXTERN PetscErrorCode KSPPIPEFCGSetNprealloc(KSP, PetscInt);
    358: PETSC_EXTERN PetscErrorCode KSPPIPEFCGGetNprealloc(KSP, PetscInt *);
    359: PETSC_EXTERN PetscErrorCode KSPPIPEFCGSetTruncationType(KSP, KSPFCDTruncationType);
    360: PETSC_EXTERN PetscErrorCode KSPPIPEFCGGetTruncationType(KSP, KSPFCDTruncationType *);

    362: PETSC_EXTERN PetscErrorCode KSPPIPEGCRSetMmax(KSP, PetscInt);
    363: PETSC_EXTERN PetscErrorCode KSPPIPEGCRGetMmax(KSP, PetscInt *);
    364: PETSC_EXTERN PetscErrorCode KSPPIPEGCRSetNprealloc(KSP, PetscInt);
    365: PETSC_EXTERN PetscErrorCode KSPPIPEGCRGetNprealloc(KSP, PetscInt *);
    366: PETSC_EXTERN PetscErrorCode KSPPIPEGCRSetTruncationType(KSP, KSPFCDTruncationType);
    367: PETSC_EXTERN PetscErrorCode KSPPIPEGCRGetTruncationType(KSP, KSPFCDTruncationType *);
    368: PETSC_EXTERN PetscErrorCode KSPPIPEGCRSetUnrollW(KSP, PetscBool);
    369: PETSC_EXTERN PetscErrorCode KSPPIPEGCRGetUnrollW(KSP, PetscBool *);

    371: /*S
    372:   KSPFlexibleModifyPCFn - A prototype of a function used to modify the preconditioner during the use of flexible `KSP` methods, such as `KSPFGMRES`

    374:   Calling Sequence:
    375: + ksp       - the `KSP` context being used.
    376: . total_its - the total number of iterations that have occurred.
    377: . local_its - the number of iterations since last restart if applicable
    378: . res_norm  - the current residual norm
    379: - ctx       - optional context variable set with `KSPFlexibleSetModifyPC()`, `KSPPIPEGCRSetModifyPC()`, `KSPGCRSetModifyPC()`, `KSPFGMRESSetModifyPC()`

    381:   Level: beginner

    383: .seealso: [](ch_ksp), `KSP`, `KSPFlexibleSetModifyPC()`, `KSPPIPEGCRSetModifyPC()`, `KSPGCRSetModifyPC()`, `KSPFGMRESSetModifyPC()`
    384: S*/
    385: PETSC_EXTERN_TYPEDEF typedef PetscErrorCode KSPFlexibleModifyPCFn(KSP ksp, PetscInt total_its, PetscInt local_its, PetscReal res_norm, void *ctx);

    387: PETSC_EXTERN PetscErrorCode KSPFlexibleSetModifyPC(KSP, KSPFlexibleModifyPCFn *, void *, PetscCtxDestroyFn *);
    388: PETSC_EXTERN PetscErrorCode KSPPIPEGCRSetModifyPC(KSP, KSPFlexibleModifyPCFn *, void *, PetscCtxDestroyFn *);

    390: PETSC_EXTERN PetscErrorCode KSPGMRESSetRestart(KSP, PetscInt);
    391: PETSC_EXTERN PetscErrorCode KSPGMRESGetRestart(KSP, PetscInt *);
    392: PETSC_EXTERN PetscErrorCode KSPGMRESSetHapTol(KSP, PetscReal);
    393: PETSC_EXTERN PetscErrorCode KSPGMRESSetBreakdownTolerance(KSP, PetscReal);

    395: PETSC_EXTERN PetscErrorCode KSPGMRESSetPreAllocateVectors(KSP);
    396: PETSC_EXTERN PetscErrorCode KSPGMRESSetOrthogonalization(KSP, PetscErrorCode (*)(KSP, PetscInt));
    397: PETSC_EXTERN PetscErrorCode KSPGMRESGetOrthogonalization(KSP, PetscErrorCode (**)(KSP, PetscInt));
    398: PETSC_EXTERN PetscErrorCode KSPGMRESModifiedGramSchmidtOrthogonalization(KSP, PetscInt);
    399: PETSC_EXTERN PetscErrorCode KSPGMRESClassicalGramSchmidtOrthogonalization(KSP, PetscInt);

    401: PETSC_EXTERN PetscErrorCode KSPLGMRESSetAugDim(KSP, PetscInt);
    402: PETSC_EXTERN PetscErrorCode KSPLGMRESSetConstant(KSP);

    404: PETSC_EXTERN PetscErrorCode KSPPIPEFGMRESSetShift(KSP, PetscScalar);

    406: PETSC_EXTERN PetscErrorCode KSPGCRSetRestart(KSP, PetscInt);
    407: PETSC_EXTERN PetscErrorCode KSPGCRGetRestart(KSP, PetscInt *);
    408: PETSC_EXTERN PetscErrorCode KSPGCRSetModifyPC(KSP, KSPFlexibleModifyPCFn *, void *, PetscCtxDestroyFn *);

    410: PETSC_EXTERN PetscErrorCode KSPMINRESSetRadius(KSP, PetscReal);
    411: PETSC_EXTERN PetscErrorCode KSPMINRESGetUseQLP(KSP, PetscBool *);
    412: PETSC_EXTERN PetscErrorCode KSPMINRESSetUseQLP(KSP, PetscBool);

    414: PETSC_EXTERN PetscErrorCode KSPFETIDPGetInnerBDDC(KSP, PC *);
    415: PETSC_EXTERN PetscErrorCode KSPFETIDPSetInnerBDDC(KSP, PC);
    416: PETSC_EXTERN PetscErrorCode KSPFETIDPGetInnerKSP(KSP, KSP *);
    417: PETSC_EXTERN PetscErrorCode KSPFETIDPSetPressureOperator(KSP, Mat);

    419: PETSC_EXTERN PetscErrorCode KSPHPDDMSetDeflationMat(KSP, Mat);
    420: PETSC_EXTERN PetscErrorCode KSPHPDDMGetDeflationMat(KSP, Mat *);
    421: #if PetscDefined(HAVE_HPDDM)
    422: PETSC_DEPRECATED_FUNCTION(3, 18, 0, "KSPHPDDMSetDeflationMat()", ) static inline PetscErrorCode KSPHPDDMSetDeflationSpace(KSP ksp, Mat U)
    423: {
    424:   return KSPHPDDMSetDeflationMat(ksp, U);
    425: }
    426: PETSC_DEPRECATED_FUNCTION(3, 18, 0, "KSPHPDDMGetDeflationMat()", ) static inline PetscErrorCode KSPHPDDMGetDeflationSpace(KSP ksp, Mat *U)
    427: {
    428:   return KSPHPDDMGetDeflationMat(ksp, U);
    429: }
    430: #endif
    431: PETSC_DEPRECATED_FUNCTION(3, 14, 0, "KSPMatSolve()", ) static inline PetscErrorCode KSPHPDDMMatSolve(KSP ksp, Mat B, Mat X)
    432: {
    433:   return KSPMatSolve(ksp, B, X);
    434: }
    435: /*E
    436:     KSPHPDDMType - Type of Krylov method used by `KSPHPDDM`

    438:     Values:
    439: +   `KSP_HPDDM_TYPE_GMRES` (default) - Generalized Minimal Residual method
    440: .   `KSP_HPDDM_TYPE_BGMRES`          - block GMRES
    441: .   `KSP_HPDDM_TYPE_CG`              - Conjugate Gradient
    442: .   `KSP_HPDDM_TYPE_BCG`             - block CG
    443: .   `KSP_HPDDM_TYPE_GCRODR`          - Generalized Conjugate Residual method with inner Orthogonalization and Deflated Restarting
    444: .   `KSP_HPDDM_TYPE_BGCRODR`         - block GCRODR
    445: .   `KSP_HPDDM_TYPE_BFBCG`           - breakdown-free BCG
    446: -   `KSP_HPDDM_TYPE_PREONLY`         - apply the preconditioner only

    448:     Level: intermediate

    450: .seealso: [](ch_ksp), `KSPHPDDM`, `KSPHPDDMSetType()`
    451: E*/
    452: typedef enum {
    453:   KSP_HPDDM_TYPE_GMRES   = 0,
    454:   KSP_HPDDM_TYPE_BGMRES  = 1,
    455:   KSP_HPDDM_TYPE_CG      = 2,
    456:   KSP_HPDDM_TYPE_BCG     = 3,
    457:   KSP_HPDDM_TYPE_GCRODR  = 4,
    458:   KSP_HPDDM_TYPE_BGCRODR = 5,
    459:   KSP_HPDDM_TYPE_BFBCG   = 6,
    460:   KSP_HPDDM_TYPE_PREONLY = 7
    461: } KSPHPDDMType;
    462: PETSC_EXTERN const char *const KSPHPDDMTypes[];

    464: /*E
    465:     KSPHPDDMPrecision - Precision of Krylov bases used by `KSPHPDDM`

    467:     Values:
    468: +   `KSP_HPDDM_PRECISION_HALF`      - default when PETSc is configured `--with-precision=__fp16`
    469: .   `KSP_HPDDM_PRECISION_SINGLE`    - default when PETSc is configured `--with-precision=single`
    470: .   `KSP_HPDDM_PRECISION_DOUBLE`    - default when PETSc is configured `--with-precision=double`
    471: -   `KSP_HPDDM_PRECISION_QUADRUPLE` - default when PETSc is configured `--with-precision=__float128`

    473:     Level: intermediate

    475: .seealso: [](ch_ksp), `KSP`, `KSPHPDDM`
    476: E*/
    477: typedef enum {
    478:   KSP_HPDDM_PRECISION_HALF      = 0,
    479:   KSP_HPDDM_PRECISION_SINGLE    = 1,
    480:   KSP_HPDDM_PRECISION_DOUBLE    = 2,
    481:   KSP_HPDDM_PRECISION_QUADRUPLE = 3
    482: } KSPHPDDMPrecision;
    483: PETSC_EXTERN PetscErrorCode KSPHPDDMSetType(KSP, KSPHPDDMType);
    484: PETSC_EXTERN PetscErrorCode KSPHPDDMGetType(KSP, KSPHPDDMType *);

    486: /*E
    487:    KSPGMRESCGSRefinementType - How the classical (unmodified) Gram-Schmidt is performed in the GMRES solvers

    489:    Values:
    490: +  `KSP_GMRES_CGS_REFINE_NEVER`    - one step of classical Gram-Schmidt
    491: .  `KSP_GMRES_CGS_REFINE_IFNEEDED` - a second step is performed if the first step does not satisfy some criteria
    492: -  `KSP_GMRES_CGS_REFINE_ALWAYS`   - always perform two steps

    494:    Level: advanced

    496: .seealso: [](ch_ksp), `KSP`, `KSPGMRES`, `KSPGMRESClassicalGramSchmidtOrthogonalization()`, `KSPGMRESSetOrthogonalization()`,
    497:           `KSPGMRESGetOrthogonalization()`,
    498:           `KSPGMRESSetCGSRefinementType()`, `KSPGMRESGetCGSRefinementType()`, `KSPGMRESModifiedGramSchmidtOrthogonalization()`
    499: E*/
    500: typedef enum {
    501:   KSP_GMRES_CGS_REFINE_NEVER,
    502:   KSP_GMRES_CGS_REFINE_IFNEEDED,
    503:   KSP_GMRES_CGS_REFINE_ALWAYS
    504: } KSPGMRESCGSRefinementType;
    505: PETSC_EXTERN const char *const KSPGMRESCGSRefinementTypes[];

    507: /*MC
    508:    KSP_GMRES_CGS_REFINE_NEVER - Do the classical (unmodified) Gram-Schmidt process

    510:    Level: advanced

    512:    Note:
    513:    Possibly unstable, but the fastest to compute

    515: .seealso: [](ch_ksp), `KSPGMRES`, `KSPGMRESCGSRefinementType`, `KSPGMRESClassicalGramSchmidtOrthogonalization()`, `KSPGMRESSetOrthogonalization()`,
    516:           `KSP`, `KSPGMRESGetOrthogonalization()`,
    517:           `KSPGMRESSetCGSRefinementType()`, `KSPGMRESGetCGSRefinementType()`, `KSP_GMRES_CGS_REFINE_IFNEEDED`, `KSP_GMRES_CGS_REFINE_ALWAYS`,
    518:           `KSPGMRESModifiedGramSchmidtOrthogonalization()`
    519: M*/

    521: /*MC
    522:     KSP_GMRES_CGS_REFINE_IFNEEDED - Do the classical (unmodified) Gram-Schmidt process and one step of
    523:           iterative refinement if an estimate of the orthogonality of the resulting vectors indicates
    524:           poor orthogonality.

    526:    Level: advanced

    528:    Note:
    529:    This is slower than `KSP_GMRES_CGS_REFINE_NEVER` because it requires an extra norm computation to
    530:    estimate the orthogonality but is more stable.

    532: .seealso: [](ch_ksp), `KSPGMRES`, `KSPGMRESCGSRefinementType`, `KSPGMRESClassicalGramSchmidtOrthogonalization()`, `KSPGMRESSetOrthogonalization()`,
    533:           `KSP`, `KSPGMRESGetOrthogonalization()`,
    534:           `KSPGMRESSetCGSRefinementType()`, `KSPGMRESGetCGSRefinementType()`, `KSP_GMRES_CGS_REFINE_NEVER`, `KSP_GMRES_CGS_REFINE_ALWAYS`,
    535:           `KSPGMRESModifiedGramSchmidtOrthogonalization()`
    536: M*/

    538: /*MC
    539:    KSP_GMRES_CGS_REFINE_ALWAYS - Do two steps of the classical (unmodified) Gram-Schmidt process.

    541:    Level: advanced

    543:    Notes:
    544:    This is roughly twice the cost of `KSP_GMRES_CGS_REFINE_NEVER` because it performs the process twice
    545:    but it saves the extra norm calculation needed by `KSP_GMRES_CGS_REFINE_IFNEEDED`.

    547:    You should only use this if you absolutely know that the iterative refinement is needed.

    549: .seealso: [](ch_ksp), `KSPGMRES`, `KSPGMRESCGSRefinementType`, `KSPGMRESClassicalGramSchmidtOrthogonalization()`, `KSPGMRESSetOrthogonalization()`,
    550:           `KSP`, `KSPGMRESGetOrthogonalization()`,
    551:           `KSPGMRESSetCGSRefinementType()`, `KSPGMRESGetCGSRefinementType()`, `KSP_GMRES_CGS_REFINE_IFNEEDED`, `KSP_GMRES_CGS_REFINE_ALWAYS`,
    552:           `KSPGMRESModifiedGramSchmidtOrthogonalization()`
    553: M*/

    555: PETSC_EXTERN PetscErrorCode KSPGMRESSetCGSRefinementType(KSP, KSPGMRESCGSRefinementType);
    556: PETSC_EXTERN PetscErrorCode KSPGMRESGetCGSRefinementType(KSP, KSPGMRESCGSRefinementType *);

    558: PETSC_EXTERN KSPFlexibleModifyPCFn KSPFGMRESModifyPCNoChange;
    559: PETSC_EXTERN KSPFlexibleModifyPCFn KSPFGMRESModifyPCKSP;
    560: PETSC_EXTERN PetscErrorCode        KSPFGMRESSetModifyPC(KSP, KSPFlexibleModifyPCFn *, void *, PetscCtxDestroyFn *);

    562: PETSC_EXTERN PetscErrorCode KSPQCGSetTrustRegionRadius(KSP, PetscReal);
    563: PETSC_EXTERN PetscErrorCode KSPQCGGetQuadratic(KSP, PetscReal *);
    564: PETSC_EXTERN PetscErrorCode KSPQCGGetTrialStepNorm(KSP, PetscReal *);

    566: PETSC_EXTERN PetscErrorCode KSPBCGSLSetXRes(KSP, PetscReal);
    567: PETSC_EXTERN PetscErrorCode KSPBCGSLSetPol(KSP, PetscBool);
    568: PETSC_EXTERN PetscErrorCode KSPBCGSLSetEll(KSP, PetscInt);
    569: PETSC_EXTERN PetscErrorCode KSPBCGSLSetUsePseudoinverse(KSP, PetscBool);

    571: PETSC_EXTERN PetscErrorCode KSPSetFromOptions(KSP);
    572: PETSC_EXTERN PetscErrorCode KSPResetFromOptions(KSP);

    574: PETSC_EXTERN PetscErrorCode       KSPMonitorSetFromOptions(KSP, const char[], const char[], void *);
    575: PETSC_EXTERN KSPMonitorRegisterFn KSPMonitorResidual;
    576: PETSC_EXTERN KSPMonitorRegisterFn KSPMonitorResidualView;
    577: PETSC_DEPRECATED_FUNCTION(3, 23, 0, "KSPMonitorResidualDraw()", ) static inline PetscErrorCode KSPMonitorResidualDraw(KSP ksp, PetscInt n, PetscReal rnorm, PetscViewerAndFormat *vf)
    578: {
    579:   return KSPMonitorResidualView(ksp, n, rnorm, vf);
    580: }
    581: PETSC_EXTERN KSPMonitorRegisterFn KSPMonitorResidualDrawLG;
    582: PETSC_EXTERN PetscErrorCode       KSPMonitorResidualDrawLGCreate(PetscViewer, PetscViewerFormat, void *, PetscViewerAndFormat **);
    583: PETSC_EXTERN KSPMonitorRegisterFn KSPMonitorResidualShort;
    584: PETSC_EXTERN KSPMonitorRegisterFn KSPMonitorResidualRange;
    585: PETSC_EXTERN KSPMonitorRegisterFn KSPMonitorTrueResidual;
    586: PETSC_EXTERN KSPMonitorRegisterFn KSPMonitorTrueResidualView;
    587: PETSC_DEPRECATED_FUNCTION(3, 23, 0, "KSPMonitorTrueResidualDraw()", ) static inline PetscErrorCode KSPMonitorTrueResidualDraw(KSP ksp, PetscInt n, PetscReal rnorm, PetscViewerAndFormat *vf)
    588: {
    589:   return KSPMonitorTrueResidualView(ksp, n, rnorm, vf);
    590: }
    591: PETSC_EXTERN KSPMonitorRegisterFn KSPMonitorTrueResidualDrawLG;
    592: PETSC_EXTERN PetscErrorCode       KSPMonitorTrueResidualDrawLGCreate(PetscViewer, PetscViewerFormat, void *, PetscViewerAndFormat **);
    593: PETSC_EXTERN KSPMonitorRegisterFn KSPMonitorTrueResidualMax;
    594: PETSC_EXTERN KSPMonitorRegisterFn KSPMonitorError;
    595: PETSC_EXTERN KSPMonitorRegisterFn KSPMonitorErrorDraw;
    596: PETSC_EXTERN KSPMonitorRegisterFn KSPMonitorErrorDrawLG;
    597: PETSC_EXTERN PetscErrorCode       KSPMonitorErrorDrawLGCreate(PetscViewer, PetscViewerFormat, void *, PetscViewerAndFormat **);
    598: PETSC_EXTERN KSPMonitorRegisterFn KSPMonitorSolution;
    599: PETSC_EXTERN KSPMonitorRegisterFn KSPMonitorSolutionDraw;
    600: PETSC_EXTERN KSPMonitorRegisterFn KSPMonitorSolutionDrawLG;
    601: PETSC_EXTERN PetscErrorCode       KSPMonitorSolutionDrawLGCreate(PetscViewer, PetscViewerFormat, void *, PetscViewerAndFormat **);
    602: PETSC_EXTERN KSPMonitorRegisterFn KSPMonitorSingularValue;
    603: PETSC_EXTERN PetscErrorCode       KSPMonitorSingularValueCreate(PetscViewer, PetscViewerFormat, void *, PetscViewerAndFormat **);
    604: PETSC_DEPRECATED_FUNCTION(3, 15, 0, "KSPMonitorResidual()", ) static inline PetscErrorCode KSPMonitorDefault(KSP ksp, PetscInt n, PetscReal rnorm, PetscViewerAndFormat *vf)
    605: {
    606:   return KSPMonitorResidual(ksp, n, rnorm, vf);
    607: }
    608: PETSC_DEPRECATED_FUNCTION(3, 15, 0, "KSPMonitorTrueResidual()", ) static inline PetscErrorCode KSPMonitorTrueResidualNorm(KSP ksp, PetscInt n, PetscReal rnorm, PetscViewerAndFormat *vf)
    609: {
    610:   return KSPMonitorTrueResidual(ksp, n, rnorm, vf);
    611: }
    612: PETSC_DEPRECATED_FUNCTION(3, 15, 0, "KSPMonitorTrueResidualMax()", ) static inline PetscErrorCode KSPMonitorTrueResidualMaxNorm(KSP ksp, PetscInt n, PetscReal rnorm, PetscViewerAndFormat *vf)
    613: {
    614:   return KSPMonitorTrueResidualMax(ksp, n, rnorm, vf);
    615: }

    617: PETSC_EXTERN PetscErrorCode KSPGMRESMonitorKrylov(KSP, PetscInt, PetscReal, void *);
    618: PETSC_EXTERN PetscErrorCode KSPMonitorDynamicTolerance(KSP, PetscInt, PetscReal, void *);
    619: PETSC_EXTERN PetscErrorCode KSPMonitorDynamicToleranceDestroy(void **);
    620: PETSC_EXTERN PetscErrorCode KSPMonitorDynamicToleranceCreate(void *);
    621: PETSC_EXTERN PetscErrorCode KSPMonitorDynamicToleranceSetCoefficient(void *, PetscReal);
    622: PETSC_EXTERN PetscErrorCode KSPMonitorSAWs(KSP, PetscInt, PetscReal, void *);
    623: PETSC_EXTERN PetscErrorCode KSPMonitorSAWsCreate(KSP, void **);
    624: PETSC_EXTERN PetscErrorCode KSPMonitorSAWsDestroy(void **);

    626: PETSC_EXTERN PetscErrorCode KSPUnwindPreconditioner(KSP, Vec, Vec);
    627: PETSC_EXTERN PetscErrorCode KSPInitialResidual(KSP, Vec, Vec, Vec, Vec, Vec);

    629: PETSC_EXTERN PetscErrorCode KSPSetOperators(KSP, Mat, Mat);
    630: PETSC_EXTERN PetscErrorCode KSPGetOperators(KSP, Mat *, Mat *);
    631: PETSC_EXTERN PetscErrorCode KSPGetOperatorsSet(KSP, PetscBool *, PetscBool *);
    632: PETSC_EXTERN PetscErrorCode KSPSetOptionsPrefix(KSP, const char[]);
    633: PETSC_EXTERN PetscErrorCode KSPAppendOptionsPrefix(KSP, const char[]);
    634: PETSC_EXTERN PetscErrorCode KSPGetOptionsPrefix(KSP, const char *[]);

    636: PETSC_EXTERN PetscErrorCode KSPSetDiagonalScale(KSP, PetscBool);
    637: PETSC_EXTERN PetscErrorCode KSPGetDiagonalScale(KSP, PetscBool *);
    638: PETSC_EXTERN PetscErrorCode KSPSetDiagonalScaleFix(KSP, PetscBool);
    639: PETSC_EXTERN PetscErrorCode KSPGetDiagonalScaleFix(KSP, PetscBool *);

    641: /*S
    642:   KSPConvergedReasonViewFn - A prototype of a function used with `KSPConvergedReasonViewSet()`

    644:   Calling Sequence:
    645: + ksp - the `KSP` object whose `KSPConvergedReason` is to be viewed
    646: - ctx - context used by the function, set with `KSPConvergedReasonViewSet()`

    648:   Level: beginner

    650: .seealso: [](ch_ksp), `KSP`, `KSPConvergedReasonView()`, `KSPConvergedReasonViewSet()`, `KSPConvergedReasonViewFromOptions()`, `KSPView()`
    651: S*/
    652: PETSC_EXTERN_TYPEDEF typedef PetscErrorCode KSPConvergedReasonViewFn(KSP ksp, void *ctx);

    654: PETSC_EXTERN PetscErrorCode KSPView(KSP, PetscViewer);
    655: PETSC_EXTERN PetscErrorCode KSPLoad(KSP, PetscViewer);
    656: PETSC_EXTERN PetscErrorCode KSPViewFromOptions(KSP, PetscObject, const char[]);
    657: PETSC_EXTERN PetscErrorCode KSPConvergedReasonView(KSP, PetscViewer);
    658: PETSC_EXTERN PetscErrorCode KSPConvergedReasonViewSet(KSP, KSPConvergedReasonViewFn *, void *, PetscCtxDestroyFn *);
    659: PETSC_EXTERN PetscErrorCode KSPConvergedReasonViewFromOptions(KSP);
    660: PETSC_EXTERN PetscErrorCode KSPConvergedReasonViewCancel(KSP);
    661: PETSC_EXTERN PetscErrorCode KSPConvergedRateView(KSP, PetscViewer);

    663: PETSC_DEPRECATED_FUNCTION(3, 14, 0, "KSPConvergedReasonView()", ) static inline PetscErrorCode KSPReasonView(KSP ksp, PetscViewer v)
    664: {
    665:   return KSPConvergedReasonView(ksp, v);
    666: }
    667: PETSC_DEPRECATED_FUNCTION(3, 14, 0, "KSPConvergedReasonViewFromOptions()", ) static inline PetscErrorCode KSPReasonViewFromOptions(KSP ksp)
    668: {
    669:   return KSPConvergedReasonViewFromOptions(ksp);
    670: }

    672: #define KSP_FILE_CLASSID 1211223

    674: PETSC_EXTERN PetscErrorCode       KSPLSQRSetExactMatNorm(KSP, PetscBool);
    675: PETSC_EXTERN PetscErrorCode       KSPLSQRSetComputeStandardErrorVec(KSP, PetscBool);
    676: PETSC_EXTERN PetscErrorCode       KSPLSQRGetStandardErrorVec(KSP, Vec *);
    677: PETSC_EXTERN PetscErrorCode       KSPLSQRGetNorms(KSP, PetscReal *, PetscReal *);
    678: PETSC_EXTERN KSPMonitorRegisterFn KSPLSQRMonitorResidual;
    679: PETSC_EXTERN KSPMonitorRegisterFn KSPLSQRMonitorResidualDrawLG;
    680: PETSC_EXTERN PetscErrorCode       KSPLSQRMonitorResidualDrawLGCreate(PetscViewer, PetscViewerFormat, void *, PetscViewerAndFormat **);

    682: PETSC_EXTERN PetscErrorCode PCRedundantGetKSP(PC, KSP *);
    683: PETSC_EXTERN PetscErrorCode PCRedistributeGetKSP(PC, KSP *);
    684: PETSC_EXTERN PetscErrorCode PCTelescopeGetKSP(PC, KSP *);
    685: PETSC_EXTERN PetscErrorCode PCMPIGetKSP(PC, KSP *);

    687: /*E
    688:    KSPNormType - Norm calculated by the `KSP` and passed in the Krylov convergence
    689:        test routines.

    691:    Values:
    692: +  `KSP_NORM_DEFAULT`          - use the default for the current `KSPType`
    693: .  `KSP_NORM_NONE`             - use no norm calculation
    694: .  `KSP_NORM_PRECONDITIONED`   - use the preconditioned residual norm
    695: .  `KSP_NORM_UNPRECONDITIONED` - use the unpreconditioned residual norm
    696: -  `KSP_NORM_NATURAL`          - use the natural norm (the norm induced by the linear operator)

    698:    Level: advanced

    700:    Note:
    701:    Each solver only supports a subset of these and some may support different ones
    702:    depending on whether left or right preconditioning is used, see `KSPSetPCSide()`

    704: .seealso: [](ch_ksp), `KSP`, `PCSide`, `KSPSolve()`, `KSPGetConvergedReason()`, `KSPSetNormType()`,
    705:           `KSPSetConvergenceTest()`, `KSPSetPCSide()`, `KSP_NORM_DEFAULT`, `KSP_NORM_NONE`, `KSP_NORM_PRECONDITIONED`, `KSP_NORM_UNPRECONDITIONED`, `KSP_NORM_NATURAL`
    706: E*/
    707: typedef enum {
    708:   KSP_NORM_DEFAULT          = -1,
    709:   KSP_NORM_NONE             = 0,
    710:   KSP_NORM_PRECONDITIONED   = 1,
    711:   KSP_NORM_UNPRECONDITIONED = 2,
    712:   KSP_NORM_NATURAL          = 3
    713: } KSPNormType;
    714: #define KSP_NORM_MAX (KSP_NORM_NATURAL + 1)
    715: PETSC_EXTERN const char *const *const KSPNormTypes;

    717: /*MC
    718:    KSP_NORM_NONE - Do not compute a norm during the Krylov process. This will
    719:    possibly save some computation but means the convergence test cannot
    720:    be based on a norm of a residual etc.

    722:    Level: advanced

    724:    Note:
    725:    Some Krylov methods need to compute a residual norm (such as `KPSGMRES`) and then this option is ignored

    727: .seealso: [](ch_ksp), `KSPNormType`, `KSP`, `KSPSetNormType()`, `KSP_NORM_PRECONDITIONED`, `KSP_NORM_UNPRECONDITIONED`, `KSP_NORM_NATURAL`
    728: M*/

    730: /*MC
    731:    KSP_NORM_PRECONDITIONED - Compute the norm of the preconditioned residual B*(b - A*x), if left preconditioning, and pass that to the
    732:    convergence test routine.

    734:    Level: advanced

    736: .seealso: [](ch_ksp), `KSPNormType`, `KSP`, `KSPSetNormType()`, `KSP_NORM_NONE`, `KSP_NORM_UNPRECONDITIONED`, `KSP_NORM_NATURAL`, `KSPSetConvergenceTest()`
    737: M*/

    739: /*MC
    740:    KSP_NORM_UNPRECONDITIONED - Compute the norm of the true residual (b - A*x) and pass that to the
    741:    convergence test routine.

    743:    Level: advanced

    745: .seealso: [](ch_ksp), `KSPNormType`, `KSP`, `KSPSetNormType()`, `KSP_NORM_NONE`, `KSP_NORM_PRECONDITIONED`, `KSP_NORM_NATURAL`, `KSPSetConvergenceTest()`
    746: M*/

    748: /*MC
    749:    KSP_NORM_NATURAL - Compute the 'natural norm' of residual sqrt((b - A*x)*B*(b - A*x)) and pass that to the
    750:    convergence test routine. This is only supported by  `KSPCG`, `KSPCR`, `KSPCGNE`, `KSPCGS`, `KSPFCG`, `KSPPIPEFCG`, `KSPPIPEGCR`

    752:    Level: advanced

    754: .seealso: [](ch_ksp), `KSPNormType`, `KSP`, `KSPSetNormType()`, `KSP_NORM_NONE`, `KSP_NORM_PRECONDITIONED`, `KSP_NORM_UNPRECONDITIONED`, `KSPSetConvergenceTest()`
    755: M*/

    757: PETSC_EXTERN PetscErrorCode KSPSetNormType(KSP, KSPNormType);
    758: PETSC_EXTERN PetscErrorCode KSPGetNormType(KSP, KSPNormType *);
    759: PETSC_EXTERN PetscErrorCode KSPSetSupportedNorm(KSP, KSPNormType, PCSide, PetscInt);
    760: PETSC_EXTERN PetscErrorCode KSPSetCheckNormIteration(KSP, PetscInt);
    761: PETSC_EXTERN PetscErrorCode KSPSetLagNorm(KSP, PetscBool);

    763: #define KSP_CONVERGED_CG_NEG_CURVE_DEPRECATED   KSP_CONVERGED_CG_NEG_CURVE PETSC_DEPRECATED_ENUM(3, 19, 0, "KSP_CONVERGED_NEG_CURVE", )
    764: #define KSP_CONVERGED_CG_CONSTRAINED_DEPRECATED KSP_CONVERGED_CG_CONSTRAINED PETSC_DEPRECATED_ENUM(3, 19, 0, "KSP_CONVERGED_STEP_LENGTH", )
    765: #define KSP_CONVERGED_RTOL_NORMAL_DEPRECATED    KSP_CONVERGED_RTOL_NORMAL PETSC_DEPRECATED_ENUM(3, 24, 0, "KSP_CONVERGED_RTOL_NORMAL_EQUATIONS", )
    766: #define KSP_CONVERGED_ATOL_NORMAL_DEPRECATED    KSP_CONVERGED_ATOL_NORMAL PETSC_DEPRECATED_ENUM(3, 24, 0, "KSP_CONVERGED_ATOL_NORMAL_EQUATIONS", )
    767: /*E
    768:    KSPConvergedReason - reason a Krylov method was determined to have converged or diverged

    770:    Values:
    771: +  `KSP_CONVERGED_RTOL_NORMAL_EQUATIONS` - requested decrease in the residual of the normal equations, for `KSPLSQR`
    772: .  `KSP_CONVERGED_ATOL_NORMAL_EQUATIONS` - requested absolute value in the residual of the normal equations, for `KSPLSQR`
    773: .  `KSP_CONVERGED_RTOL`                  - requested decrease in the residual
    774: .  `KSP_CONVERGED_ATOL`                  - requested absolute value in the residual
    775: .  `KSP_CONVERGED_ITS`                   - requested number of iterations
    776: .  `KSP_CONVERGED_NEG_CURVE`             - see note below
    777: .  `KSP_CONVERGED_STEP_LENGTH`           - see note below
    778: .  `KSP_CONVERGED_HAPPY_BREAKDOWN`       - happy breakdown (meaning early convergence of the `KSPType` occurred).
    779: .  `KSP_CONVERGED_USER`                  - the user has indicated convergence for an arbitrary reason
    780: .  `KSP_DIVERGED_NULL`                   - breakdown when solving the Hessenberg system within `KSPGMRES`
    781: .  `KSP_DIVERGED_ITS`                    - requested number of iterations
    782: .  `KSP_DIVERGED_DTOL`                   - large increase in the residual norm indicating the solution is diverging
    783: .  `KSP_DIVERGED_BREAKDOWN`              - breakdown in the Krylov method
    784: .  `KSP_DIVERGED_BREAKDOWN_BICG`         - breakdown in the `KSPBCGS` Krylov method
    785: .  `KSP_DIVERGED_NONSYMMETRIC`           - the operator or preonditioner was not symmetric for a `KSPType` that requires symmetry
    786: .  `KSP_DIVERGED_INDEFINITE_PC`          - the preconditioner was indefinite for a `KSPType` that requires it be definite, such as `KSPCG`
    787: .  `KSP_DIVERGED_NANORINF`               - a not a number of infinity was detected in a vector during the computation
    788: .  `KSP_DIVERGED_INDEFINITE_MAT`         - the operator was indefinite for a `KSPType` that requires it be definite, such as `KSPCG`
    789: .  `KSP_DIVERGED_PC_FAILED`              - the action of the preconditioner failed for some reason
    790: -  `KSP_DIVERGED_USER`                   - the user has indicated divergence for an arbitrary reason

    792:    Level: beginner

    794:    Note:
    795:    The values `KSP_CONVERGED_NEG_CURVE`, and `KSP_CONVERGED_STEP_LENGTH` are returned only by `KSPCG`, `KSPMINRES` and by
    796:    the special `KSPNASH`, `KSPSTCG`, and `KSPGLTR` solvers which are used by the `SNESNEWTONTR` (trust region) solver.

    798:    Developer Note:
    799:    The string versions of these are `KSPConvergedReasons`; if you change
    800:    any of the values here also change them that array of names.

    802: .seealso: [](ch_ksp), `KSP`, `KSPSolve()`, `KSPGetConvergedReason()`, `KSPSetTolerances()`, `KSPConvergedReasonView()`
    803: E*/
    804: typedef enum { /* converged */
    805:   KSP_CONVERGED_RTOL_NORMAL_DEPRECATED    = 1,
    806:   KSP_CONVERGED_RTOL_NORMAL_EQUATIONS     = 1,
    807:   KSP_CONVERGED_ATOL_NORMAL_DEPRECATED    = 9,
    808:   KSP_CONVERGED_ATOL_NORMAL_EQUATIONS     = 9,
    809:   KSP_CONVERGED_RTOL                      = 2,
    810:   KSP_CONVERGED_ATOL                      = 3,
    811:   KSP_CONVERGED_ITS                       = 4,
    812:   KSP_CONVERGED_NEG_CURVE                 = 5,
    813:   KSP_CONVERGED_CG_NEG_CURVE_DEPRECATED   = 5,
    814:   KSP_CONVERGED_CG_CONSTRAINED_DEPRECATED = 6,
    815:   KSP_CONVERGED_STEP_LENGTH               = 6,
    816:   KSP_CONVERGED_HAPPY_BREAKDOWN           = 7,
    817:   KSP_CONVERGED_USER                      = 8,
    818:   /* diverged */
    819:   KSP_DIVERGED_NULL                      = -2,
    820:   KSP_DIVERGED_ITS                       = -3,
    821:   KSP_DIVERGED_DTOL                      = -4,
    822:   KSP_DIVERGED_BREAKDOWN                 = -5,
    823:   KSP_DIVERGED_BREAKDOWN_BICG            = -6,
    824:   KSP_DIVERGED_NONSYMMETRIC              = -7,
    825:   KSP_DIVERGED_INDEFINITE_PC             = -8,
    826:   KSP_DIVERGED_NANORINF                  = -9,
    827:   KSP_DIVERGED_INDEFINITE_MAT            = -10,
    828:   KSP_DIVERGED_PC_FAILED                 = -11,
    829:   KSP_DIVERGED_PCSETUP_FAILED_DEPRECATED = -11,
    830:   KSP_DIVERGED_USER                      = -12,

    832:   KSP_CONVERGED_ITERATING = 0
    833: } KSPConvergedReason;
    834: PETSC_EXTERN const char *const *KSPConvergedReasons;

    836: /*MC
    837:    KSP_CONVERGED_RTOL - $||r|| \le rtol*||b||$ or $rtol*||b - A*x_0||$ if `KSPConvergedDefaultSetUIRNorm()` was called

    839:    Level: beginner

    841:    Notes:
    842:    See `KSPNormType` and `KSPSetNormType()` for possible norms that may be used. By default
    843:    for left preconditioning it is the 2-norm of the preconditioned residual, and the
    844:    2-norm of the residual for right preconditioning

    846:    See also `KSP_CONVERGED_ATOL` which may apply before this tolerance.

    848: .seealso: [](ch_ksp), `KSPNormType`, `KSP_CONVERGED_ATOL`, `KSP_DIVERGED_DTOL`, `KSPSolve()`, `KSPGetConvergedReason()`, `KSPConvergedReason`, `KSPSetTolerances()`
    849: M*/

    851: /*MC
    852:    KSP_CONVERGED_ATOL - $||r|| \le atol$

    854:    Level: beginner

    856:    Notes:
    857:    See `KSPNormType` and `KSPSetNormType()` for possible norms that may be used. By default
    858:    for left preconditioning it is the 2-norm of the preconditioned residual, and the
    859:    2-norm of the residual for right preconditioning

    861:    See also `KSP_CONVERGED_RTOL` which may apply before this tolerance.

    863: .seealso: [](ch_ksp), `KSPNormType`, `KSP_CONVERGED_RTOL`, `KSP_DIVERGED_DTOL`, `KSPSolve()`, `KSPGetConvergedReason()`, `KSPConvergedReason`, `KSPSetTolerances()`
    864: M*/

    866: /*MC
    867:    KSP_DIVERGED_DTOL - $||r|| \ge dtol*||b||$

    869:    Level: beginner

    871:    Note:
    872:    See `KSPNormType` and `KSPSetNormType()` for possible norms that may be used. By default
    873:    for left preconditioning it is the 2-norm of the preconditioned residual, and the
    874:    2-norm of the residual for right preconditioning

    876: .seealso: [](ch_ksp), `KSPNormType`, `KSP_CONVERGED_ATOL`, `KSP_CONVERGED_RTOL`, `KSPSolve()`, `KSPGetConvergedReason()`, `KSPConvergedReason`, `KSPSetTolerances()`
    877: M*/

    879: /*MC
    880:    KSP_DIVERGED_ITS - Ran out of iterations before any convergence criteria was
    881:    reached

    883:    Level: beginner

    885: .seealso: [](ch_ksp), `KSPSolve()`, `KSPGetConvergedReason()`, `KSPConvergedReason`, `KSPSetTolerances()`
    886: M*/

    888: /*MC
    889:    KSP_CONVERGED_ITS - Used by the `KSPPREONLY` solver after the single iteration of
    890:    the preconditioner is applied. Also used when the `KSPConvergedSkip()` convergence
    891:    test routine is set in `KSP`.

    893:    Level: beginner

    895: .seealso: [](ch_ksp), `KSPSolve()`, `KSPGetConvergedReason()`, `KSPConvergedReason`, `KSPSetTolerances()`
    896: M*/

    898: /*MC
    899:    KSP_DIVERGED_BREAKDOWN - A breakdown in the Krylov method was detected so the
    900:    method could not continue to enlarge the Krylov space. Could be due to a singular matrix or
    901:    preconditioner. In `KSPHPDDM`, this is also returned when some search directions within a block
    902:    are collinear.

    904:    Level: beginner

    906: .seealso: [](ch_ksp), `KSPSolve()`, `KSPGetConvergedReason()`, `KSPConvergedReason`, `KSPSetTolerances()`
    907: M*/

    909: /*MC
    910:    KSP_DIVERGED_BREAKDOWN_BICG - A breakdown in the `KSPBICG` method was detected so the
    911:    method could not continue to enlarge the Krylov space.

    913:    Level: beginner

    915: .seealso: [](ch_ksp), `KSPSolve()`, `KSPGetConvergedReason()`, `KSPConvergedReason`, `KSPSetTolerances()`
    916: M*/

    918: /*MC
    919:    KSP_DIVERGED_NONSYMMETRIC - It appears the operator or preconditioner is not
    920:    symmetric and this Krylov method (`KSPCG`, `KSPMINRES`, `KSPCR`) requires symmetry

    922:    Level: beginner

    924: .seealso: [](ch_ksp), `KSPSolve()`, `KSPGetConvergedReason()`, `KSPConvergedReason`, `KSPSetTolerances()`
    925: M*/

    927: /*MC
    928:    KSP_DIVERGED_INDEFINITE_PC - It appears the preconditioner is indefinite (has both
    929:    positive and negative eigenvalues) and this Krylov method (`KSPCG`) requires it to
    930:    be symmetric positive definite (SPD).

    932:    Level: beginner

    934:    Note:
    935:    This can happen with the `PCICC` preconditioner, use the options database option `-pc_factor_shift_positive_definite` to force
    936:    the `PCICC` preconditioner to generate a positive definite preconditioner

    938: .seealso: [](ch_ksp), `KSPSolve()`, `KSPGetConvergedReason()`, `KSPConvergedReason`, `KSPSetTolerances()`
    939: M*/

    941: /*MC
    942:    KSP_DIVERGED_PC_FAILED - It was not possible to build or use the requested preconditioner. This is usually due to a
    943:    zero pivot in a factorization. It can also result from a failure in a subpreconditioner inside a nested preconditioner
    944:    such as `PCFIELDSPLIT`.

    946:    Level: beginner

    948:    Note:
    949:    Run with `-ksp_error_if_not_converged` to stop the program when the error is detected and print an error message with details.

    951: .seealso: [](ch_ksp), `KSPSolve()`, `KSPGetConvergedReason()`, `KSPConvergedReason`, `KSPSetTolerances()`
    952: M*/

    954: /*MC
    955:    KSP_CONVERGED_ITERATING - This flag is returned if `KSPGetConvergedReason()` is called
    956:    while `KSPSolve()` is still running.

    958:    Level: beginner

    960: .seealso: [](ch_ksp), `KSPSolve()`, `KSPGetConvergedReason()`, `KSPConvergedReason`, `KSPSetTolerances()`
    961: M*/

    963: /*S
    964:   KSPConvergenceTestFn - A prototype of a function used with `KSPSetConvergenceTest()`

    966:   Calling Sequence:
    967: + ksp    - iterative solver obtained from `KSPCreate()`
    968: . it     - iteration number
    969: . rnorm  - (estimated) 2-norm of (preconditioned) residual
    970: . reason - the reason why it has converged or diverged
    971: - ctx    - optional convergence context, as set by `KSPSetConvergenceTest()`

    973:   Level: beginner

    975: .seealso: [](ch_ksp), `KSP`, `KSPSetConvergenceTest()`, `KSPGetConvergenceTest()`
    976: S*/
    977: PETSC_EXTERN_TYPEDEF typedef PetscErrorCode KSPConvergenceTestFn(KSP ksp, PetscInt it, PetscReal rnorm, KSPConvergedReason *reason, void *ctx);

    979: PETSC_EXTERN PetscErrorCode       KSPSetConvergenceTest(KSP, KSPConvergenceTestFn *, void *, PetscCtxDestroyFn *);
    980: PETSC_EXTERN PetscErrorCode       KSPGetConvergenceTest(KSP, KSPConvergenceTestFn **, void **, PetscCtxDestroyFn **);
    981: PETSC_EXTERN PetscErrorCode       KSPGetAndClearConvergenceTest(KSP, KSPConvergenceTestFn **, void **, PetscCtxDestroyFn **);
    982: PETSC_EXTERN PetscErrorCode       KSPGetConvergenceContext(KSP, void *);
    983: PETSC_EXTERN KSPConvergenceTestFn KSPConvergedDefault;
    984: PETSC_EXTERN KSPConvergenceTestFn KSPLSQRConvergedDefault;
    985: PETSC_EXTERN PetscCtxDestroyFn    KSPConvergedDefaultDestroy;
    986: PETSC_EXTERN PetscErrorCode       KSPConvergedDefaultCreate(void **);
    987: PETSC_EXTERN PetscErrorCode       KSPConvergedDefaultSetUIRNorm(KSP);
    988: PETSC_EXTERN PetscErrorCode       KSPConvergedDefaultSetUMIRNorm(KSP);
    989: PETSC_EXTERN PetscErrorCode       KSPConvergedDefaultSetConvergedMaxits(KSP, PetscBool);
    990: PETSC_EXTERN PetscErrorCode       KSPConvergedSkip(KSP, PetscInt, PetscReal, KSPConvergedReason *, void *);
    991: PETSC_EXTERN PetscErrorCode       KSPGetConvergedReason(KSP, KSPConvergedReason *);
    992: PETSC_EXTERN PetscErrorCode       KSPGetConvergedReasonString(KSP, const char *[]);
    993: PETSC_EXTERN PetscErrorCode       KSPComputeConvergenceRate(KSP, PetscReal *, PetscReal *, PetscReal *, PetscReal *);
    994: PETSC_EXTERN PetscErrorCode       KSPSetConvergedNegativeCurvature(KSP, PetscBool);
    995: PETSC_EXTERN PetscErrorCode       KSPGetConvergedNegativeCurvature(KSP, PetscBool *);

    997: PETSC_DEPRECATED_FUNCTION(3, 5, 0, "KSPConvergedDefault()", ) static inline void KSPDefaultConverged(void)
    998: { /* never called */
    999: }
    1000: #define KSPDefaultConverged (KSPDefaultConverged, KSPConvergedDefault)
    1001: PETSC_DEPRECATED_FUNCTION(3, 5, 0, "KSPConvergedDefaultDestroy()", ) static inline void KSPDefaultConvergedDestroy(void)
    1002: { /* never called */
    1003: }
    1004: #define KSPDefaultConvergedDestroy (KSPDefaultConvergedDestroy, KSPConvergedDefaultDestroy)
    1005: PETSC_DEPRECATED_FUNCTION(3, 5, 0, "KSPConvergedDefaultCreate()", ) static inline void KSPDefaultConvergedCreate(void)
    1006: { /* never called */
    1007: }
    1008: #define KSPDefaultConvergedCreate (KSPDefaultConvergedCreate, KSPConvergedDefaultCreate)
    1009: PETSC_DEPRECATED_FUNCTION(3, 5, 0, "KSPConvergedDefaultSetUIRNorm()", ) static inline void KSPDefaultConvergedSetUIRNorm(void)
    1010: { /* never called */
    1011: }
    1012: #define KSPDefaultConvergedSetUIRNorm (KSPDefaultConvergedSetUIRNorm, KSPConvergedDefaultSetUIRNorm)
    1013: PETSC_DEPRECATED_FUNCTION(3, 5, 0, "KSPConvergedDefaultSetUMIRNorm()", ) static inline void KSPDefaultConvergedSetUMIRNorm(void)
    1014: { /* never called */
    1015: }
    1016: #define KSPDefaultConvergedSetUMIRNorm (KSPDefaultConvergedSetUMIRNorm, KSPConvergedDefaultSetUMIRNorm)
    1017: PETSC_DEPRECATED_FUNCTION(3, 5, 0, "KSPConvergedSkip()", ) static inline void KSPSkipConverged(void)
    1018: { /* never called */
    1019: }
    1020: #define KSPSkipConverged (KSPSkipConverged, KSPConvergedSkip)

    1022: PETSC_EXTERN PetscErrorCode KSPComputeOperator(KSP, MatType, Mat *);
    1023: PETSC_DEPRECATED_FUNCTION(3, 12, 0, "KSPComputeOperator()", ) static inline PetscErrorCode KSPComputeExplicitOperator(KSP A, Mat *B)
    1024: {
    1025:   return KSPComputeOperator(A, PETSC_NULLPTR, B);
    1026: }

    1028: /*E
    1029:    KSPCGType - Determines what type of `KSPCG` to use

    1031:    Values:
    1032:  + `KSP_CG_SYMMETRIC` - the matrix is complex symmetric
    1033:  - `KSP_CG_HERMITIAN` - the matrix is complex Hermitian

    1035:    Level: beginner

    1037: .seealso: [](ch_ksp), `KSPCG`, `KSP`, `KSPCGSetType()`
    1038: E*/
    1039: typedef enum {
    1040:   KSP_CG_SYMMETRIC = 0,
    1041:   KSP_CG_HERMITIAN = 1
    1042: } KSPCGType;
    1043: PETSC_EXTERN const char *const KSPCGTypes[];

    1045: PETSC_EXTERN PetscErrorCode KSPCGSetType(KSP, KSPCGType);
    1046: PETSC_EXTERN PetscErrorCode KSPCGUseSingleReduction(KSP, PetscBool);

    1048: PETSC_EXTERN PetscErrorCode KSPCGSetRadius(KSP, PetscReal);
    1049: PETSC_EXTERN PetscErrorCode KSPCGSetObjectiveTarget(KSP, PetscReal);
    1050: PETSC_EXTERN PetscErrorCode KSPCGGetNormD(KSP, PetscReal *);
    1051: PETSC_EXTERN PetscErrorCode KSPCGGetObjFcn(KSP, PetscReal *);

    1053: PETSC_EXTERN PetscErrorCode KSPGLTRGetMinEig(KSP, PetscReal *);
    1054: PETSC_EXTERN PetscErrorCode KSPGLTRGetLambda(KSP, PetscReal *);
    1055: PETSC_DEPRECATED_FUNCTION(3, 12, 0, "KSPGLTRGetMinEig()", ) static inline PetscErrorCode KSPCGGLTRGetMinEig(KSP ksp, PetscReal *x)
    1056: {
    1057:   return KSPGLTRGetMinEig(ksp, x);
    1058: }
    1059: PETSC_DEPRECATED_FUNCTION(3, 12, 0, "KSPGLTRGetLambda()", ) static inline PetscErrorCode KSPCGGLTRGetLambda(KSP ksp, PetscReal *x)
    1060: {
    1061:   return KSPGLTRGetLambda(ksp, x);
    1062: }

    1064: PETSC_EXTERN PetscErrorCode KSPPythonSetType(KSP, const char[]);
    1065: PETSC_EXTERN PetscErrorCode KSPPythonGetType(KSP, const char *[]);

    1067: PETSC_EXTERN PetscErrorCode PCPreSolve(PC, KSP);
    1068: PETSC_EXTERN PetscErrorCode PCPostSolve(PC, KSP);

    1070: PETSC_EXTERN PetscErrorCode KSPMonitorLGRange(KSP, PetscInt, PetscReal, void *);

    1072: /*S
    1073:   PCShellPSolveFn - A function prototype for functions provided to `PCShellSetPreSolve()` and `PCShellSetPostSolve()`

    1075:   Calling Sequence:
    1076: + pc  - the preconditioner `PC` context
    1077: . ksp - the `KSP` context
    1078: . xin  - input vector
    1079: - xout - output vector

    1081:   Level: intermediate

    1083: .seealso: [](ch_snes), `KSPPSolveFn`, `KSP`, `PCShellSetPreSolve()`, `PCShellSetPostSolve()`
    1084: S*/
    1085: PETSC_EXTERN_TYPEDEF typedef PetscErrorCode PCShellPSolveFn(PC pc, KSP ksp, Vec xim, Vec xout);

    1087: PETSC_EXTERN PetscErrorCode PCShellSetPreSolve(PC, PCShellPSolveFn *);
    1088: PETSC_EXTERN PetscErrorCode PCShellSetPostSolve(PC, PCShellPSolveFn *);

    1090: /*S
    1091:    KSPGuess - Abstract PETSc object that manages all initial guess generation methods for Krylov methods.

    1093:    Level: intermediate

    1095:    Note:
    1096:    These methods generate initial guesses based on a series of previous, related, linear solves. For example,
    1097:    in implicit time-stepping with `TS`.

    1099: .seealso: [](ch_ksp), `KSPCreate()`, `KSPGuessSetType()`, `KSPGuessType`
    1100: S*/
    1101: typedef struct _p_KSPGuess *KSPGuess;

    1103: /*J
    1104:    KSPGuessType - String with the name of a PETSc initial guess approach for Krylov methods.

    1106:    Values:
    1107:  + `KSPGUESSFISCHER` - methodology developed by Paul Fischer
    1108:  - `KSPGUESSPOD`     - methodology based on proper orthogonal decomposition (POD)

    1110:    Level: intermediate

    1112: .seealso: [](ch_ksp), `KSP`, `KSPGuess`
    1113: J*/
    1114: typedef const char *KSPGuessType;
    1115: #define KSPGUESSFISCHER "fischer"
    1116: #define KSPGUESSPOD     "pod"

    1118: PETSC_EXTERN PetscErrorCode KSPGuessRegister(const char[], PetscErrorCode (*)(KSPGuess));
    1119: PETSC_EXTERN PetscErrorCode KSPSetGuess(KSP, KSPGuess);
    1120: PETSC_EXTERN PetscErrorCode KSPGetGuess(KSP, KSPGuess *);
    1121: PETSC_EXTERN PetscErrorCode KSPGuessView(KSPGuess, PetscViewer);
    1122: PETSC_EXTERN PetscErrorCode KSPGuessDestroy(KSPGuess *);
    1123: PETSC_EXTERN PetscErrorCode KSPGuessCreate(MPI_Comm, KSPGuess *);
    1124: PETSC_EXTERN PetscErrorCode KSPGuessSetType(KSPGuess, KSPGuessType);
    1125: PETSC_EXTERN PetscErrorCode KSPGuessGetType(KSPGuess, KSPGuessType *);
    1126: PETSC_EXTERN PetscErrorCode KSPGuessSetTolerance(KSPGuess, PetscReal);
    1127: PETSC_EXTERN PetscErrorCode KSPGuessSetUp(KSPGuess);
    1128: PETSC_EXTERN PetscErrorCode KSPGuessUpdate(KSPGuess, Vec, Vec);
    1129: PETSC_EXTERN PetscErrorCode KSPGuessFormGuess(KSPGuess, Vec, Vec);
    1130: PETSC_EXTERN PetscErrorCode KSPGuessSetFromOptions(KSPGuess);
    1131: PETSC_EXTERN PetscErrorCode KSPGuessFischerSetModel(KSPGuess, PetscInt, PetscInt);
    1132: PETSC_EXTERN PetscErrorCode KSPSetUseFischerGuess(KSP, PetscInt, PetscInt);
    1133: PETSC_EXTERN PetscErrorCode KSPSetInitialGuessKnoll(KSP, PetscBool);
    1134: PETSC_EXTERN PetscErrorCode KSPGetInitialGuessKnoll(KSP, PetscBool *);

    1136: /*E
    1137:     MatSchurComplementAinvType - Determines how to approximate the inverse of the (0,0) block in Schur complement matrix assembly routines

    1139:     Level: intermediate

    1141: .seealso: `MatSchurComplementGetAinvType()`, `MatSchurComplementSetAinvType()`, `MatSchurComplementGetPmat()`, `MatGetSchurComplement()`,
    1142:           `MatCreateSchurComplementPmat()`, `MatCreateSchurComplement()`
    1143: E*/
    1144: typedef enum {
    1145:   MAT_SCHUR_COMPLEMENT_AINV_DIAG,
    1146:   MAT_SCHUR_COMPLEMENT_AINV_LUMP,
    1147:   MAT_SCHUR_COMPLEMENT_AINV_BLOCK_DIAG,
    1148:   MAT_SCHUR_COMPLEMENT_AINV_FULL
    1149: } MatSchurComplementAinvType;
    1150: PETSC_EXTERN const char *const MatSchurComplementAinvTypes[];

    1152: PETSC_EXTERN PetscErrorCode MatCreateSchurComplement(Mat, Mat, Mat, Mat, Mat, Mat *);
    1153: PETSC_EXTERN PetscErrorCode MatSchurComplementGetKSP(Mat, KSP *);
    1154: PETSC_EXTERN PetscErrorCode MatSchurComplementSetKSP(Mat, KSP);
    1155: PETSC_EXTERN PetscErrorCode MatSchurComplementSetSubMatrices(Mat, Mat, Mat, Mat, Mat, Mat);
    1156: PETSC_EXTERN PetscErrorCode MatSchurComplementUpdateSubMatrices(Mat, Mat, Mat, Mat, Mat, Mat);
    1157: PETSC_EXTERN PetscErrorCode MatSchurComplementGetSubMatrices(Mat, Mat *, Mat *, Mat *, Mat *, Mat *);
    1158: PETSC_EXTERN PetscErrorCode MatSchurComplementSetAinvType(Mat, MatSchurComplementAinvType);
    1159: PETSC_EXTERN PetscErrorCode MatSchurComplementGetAinvType(Mat, MatSchurComplementAinvType *);
    1160: PETSC_EXTERN PetscErrorCode MatSchurComplementGetPmat(Mat, MatReuse, Mat *);
    1161: PETSC_EXTERN PetscErrorCode MatSchurComplementComputeExplicitOperator(Mat, Mat *);
    1162: PETSC_EXTERN PetscErrorCode MatGetSchurComplement(Mat, IS, IS, IS, IS, MatReuse, Mat *, MatSchurComplementAinvType, MatReuse, Mat *);
    1163: PETSC_EXTERN PetscErrorCode MatCreateSchurComplementPmat(Mat, Mat, Mat, Mat, MatSchurComplementAinvType, MatReuse, Mat *);

    1165: PETSC_EXTERN PetscErrorCode MatCreateLMVMDFP(MPI_Comm, PetscInt, PetscInt, Mat *);
    1166: PETSC_EXTERN PetscErrorCode MatCreateLMVMBFGS(MPI_Comm, PetscInt, PetscInt, Mat *);
    1167: PETSC_EXTERN PetscErrorCode MatCreateLMVMDBFGS(MPI_Comm, PetscInt, PetscInt, Mat *);
    1168: PETSC_EXTERN PetscErrorCode MatCreateLMVMDDFP(MPI_Comm, PetscInt, PetscInt, Mat *);
    1169: PETSC_EXTERN PetscErrorCode MatCreateLMVMDQN(MPI_Comm, PetscInt, PetscInt, Mat *);
    1170: PETSC_EXTERN PetscErrorCode MatCreateLMVMSR1(MPI_Comm, PetscInt, PetscInt, Mat *);
    1171: PETSC_EXTERN PetscErrorCode MatCreateLMVMBroyden(MPI_Comm, PetscInt, PetscInt, Mat *);
    1172: PETSC_EXTERN PetscErrorCode MatCreateLMVMBadBroyden(MPI_Comm, PetscInt, PetscInt, Mat *);
    1173: PETSC_EXTERN PetscErrorCode MatCreateLMVMSymBroyden(MPI_Comm, PetscInt, PetscInt, Mat *);
    1174: PETSC_EXTERN PetscErrorCode MatCreateLMVMSymBadBroyden(MPI_Comm, PetscInt, PetscInt, Mat *);
    1175: PETSC_EXTERN PetscErrorCode MatCreateLMVMDiagBroyden(MPI_Comm, PetscInt, PetscInt, Mat *);

    1177: PETSC_EXTERN PetscErrorCode MatLMVMUpdate(Mat, Vec, Vec);
    1178: PETSC_EXTERN PetscErrorCode MatLMVMIsAllocated(Mat, PetscBool *);
    1179: PETSC_EXTERN PetscErrorCode MatLMVMAllocate(Mat, Vec, Vec);
    1180: PETSC_EXTERN PetscErrorCode MatLMVMReset(Mat, PetscBool);
    1181: PETSC_EXTERN PetscErrorCode MatLMVMResetShift(Mat);
    1182: PETSC_EXTERN PetscErrorCode MatLMVMClearJ0(Mat);
    1183: PETSC_EXTERN PetscErrorCode MatLMVMSetJ0(Mat, Mat);
    1184: PETSC_EXTERN PetscErrorCode MatLMVMSetJ0Scale(Mat, PetscReal);
    1185: PETSC_EXTERN PetscErrorCode MatLMVMSetJ0Diag(Mat, Vec);
    1186: PETSC_EXTERN PetscErrorCode MatLMVMSetJ0PC(Mat, PC);
    1187: PETSC_EXTERN PetscErrorCode MatLMVMSetJ0KSP(Mat, KSP);
    1188: PETSC_EXTERN PetscErrorCode MatLMVMApplyJ0Fwd(Mat, Vec, Vec);
    1189: PETSC_EXTERN PetscErrorCode MatLMVMApplyJ0Inv(Mat, Vec, Vec);
    1190: PETSC_EXTERN PetscErrorCode MatLMVMGetLastUpdate(Mat, Vec *, Vec *);
    1191: PETSC_EXTERN PetscErrorCode MatLMVMGetJ0(Mat, Mat *);
    1192: PETSC_EXTERN PetscErrorCode MatLMVMGetJ0PC(Mat, PC *);
    1193: PETSC_EXTERN PetscErrorCode MatLMVMGetJ0KSP(Mat, KSP *);
    1194: PETSC_EXTERN PetscErrorCode MatLMVMSetHistorySize(Mat, PetscInt);
    1195: PETSC_EXTERN PetscErrorCode MatLMVMGetHistorySize(Mat, PetscInt *);
    1196: PETSC_EXTERN PetscErrorCode MatLMVMGetUpdateCount(Mat, PetscInt *);
    1197: PETSC_EXTERN PetscErrorCode MatLMVMGetRejectCount(Mat, PetscInt *);
    1198: PETSC_EXTERN PetscErrorCode MatLMVMSymBroydenSetDelta(Mat, PetscScalar);

    1200: /*E
    1201:   MatLMVMMultAlgorithm - The type of algorithm used for matrix-vector products and solves used internally by a `MatLMVM` matrix

    1203:   Values:
    1204: + `MAT_LMVM_MULT_RECURSIVE`     - Use recursive formulas for products and solves
    1205: . `MAT_LMVM_MULT_DENSE`         - Use dense formulas for products and solves when possible
    1206: - `MAT_LMVM_MULT_COMPACT_DENSE` - The same as `MATLMVM_MULT_DENSE`, but go further and ensure products and solves are computed in compact low-rank update form

    1208:   Level: advanced

    1210:   Options Database Keys:
    1211: . -mat_lmvm_mult_algorithm  - the algorithm to use for multiplication (recursive, dense, compact_dense)

    1213: .seealso: [](ch_matrices), `MatLMVM`, `MatLMVMSetMultAlgorithm()`, `MatLMVMGetMultAlgorithm()`
    1214: E*/
    1215: typedef enum {
    1216:   MAT_LMVM_MULT_RECURSIVE,
    1217:   MAT_LMVM_MULT_DENSE,
    1218:   MAT_LMVM_MULT_COMPACT_DENSE,
    1219: } MatLMVMMultAlgorithm;

    1221: PETSC_EXTERN const char *const MatLMVMMultAlgorithms[];

    1223: PETSC_EXTERN PetscErrorCode MatLMVMSetMultAlgorithm(Mat, MatLMVMMultAlgorithm);
    1224: PETSC_EXTERN PetscErrorCode MatLMVMGetMultAlgorithm(Mat, MatLMVMMultAlgorithm *);

    1226: /*E
    1227:   MatLMVMSymBroydenScaleType - Rescaling type for the initial Hessian of a symmetric Broyden matrix.

    1229:   Values:
    1230: + `MAT_LMVM_SYMBROYDEN_SCALE_NONE`     - no rescaling
    1231: . `MAT_LMVM_SYMBROYDEN_SCALE_SCALAR`   - scalar rescaling
    1232: . `MAT_LMVM_SYMBROYDEN_SCALE_DIAGONAL` - diagonal rescaling
    1233: . `MAT_LMVM_SYMBROYDEN_SCALE_USER`     - same as `MAT_LMVM_SYMBROYDN_SCALE_NONE`
    1234: - `MAT_LMVM_SYMBROYDEN_SCALE_DECIDE`   - let PETSc decide rescaling

    1236:   Level: intermediate

    1238: .seealso: [](ch_matrices), `MatLMVM`, `MatLMVMSymBroydenSetScaleType()`
    1239: E*/
    1240: typedef enum {
    1241:   MAT_LMVM_SYMBROYDEN_SCALE_NONE     = 0,
    1242:   MAT_LMVM_SYMBROYDEN_SCALE_SCALAR   = 1,
    1243:   MAT_LMVM_SYMBROYDEN_SCALE_DIAGONAL = 2,
    1244:   MAT_LMVM_SYMBROYDEN_SCALE_USER     = 3,
    1245:   MAT_LMVM_SYMBROYDEN_SCALE_DECIDE   = 4
    1246: } MatLMVMSymBroydenScaleType;
    1247: PETSC_EXTERN const char *const MatLMVMSymBroydenScaleTypes[];

    1249: PETSC_EXTERN PetscErrorCode MatLMVMSymBroydenSetScaleType(Mat, MatLMVMSymBroydenScaleType);
    1250: PETSC_EXTERN PetscErrorCode MatLMVMSymBroydenGetPhi(Mat, PetscReal *);
    1251: PETSC_EXTERN PetscErrorCode MatLMVMSymBroydenSetPhi(Mat, PetscReal);
    1252: PETSC_EXTERN PetscErrorCode MatLMVMSymBadBroydenGetPsi(Mat, PetscReal *);
    1253: PETSC_EXTERN PetscErrorCode MatLMVMSymBadBroydenSetPsi(Mat, PetscReal);

    1255: /*E
    1256:   MatLMVMDenseType - Memory storage strategy for dense variants of `MATLMVM`.

    1258:   Values:
    1259: + `MAT_LMVM_DENSE_REORDER` - reorders memory to minimize kernel launch
    1260: - `MAT_LMVM_DENSE_INPLACE` - computes inplace to minimize memory movement

    1262:   Level: intermediate

    1264: .seealso: [](ch_matrices), `MatLMVM`, `MatLMVMDenseSetType()`
    1265: E*/
    1266: typedef enum {
    1267:   MAT_LMVM_DENSE_REORDER,
    1268:   MAT_LMVM_DENSE_INPLACE
    1269: } MatLMVMDenseType;
    1270: PETSC_EXTERN const char *const MatLMVMDenseTypes[];

    1272: PETSC_EXTERN PetscErrorCode MatLMVMDenseSetType(Mat, MatLMVMDenseType);

    1274: PETSC_EXTERN PetscErrorCode KSPSetDM(KSP, DM);
    1275: PETSC_EXTERN PetscErrorCode KSPSetDMActive(KSP, PetscBool);
    1276: PETSC_EXTERN PetscErrorCode KSPGetDM(KSP, DM *);
    1277: PETSC_EXTERN PetscErrorCode KSPSetApplicationContext(KSP, void *);
    1278: PETSC_EXTERN PetscErrorCode KSPGetApplicationContext(KSP, void *);

    1280: /*S
    1281:   KSPComputeRHSFn - A prototype of a `KSP` evaluation function that would be passed to `KSPSetComputeRHS()`

    1283:   Calling Sequence:
    1284: + ksp  - `ksp` context
    1285: . b    - output vector
    1286: - ctx - [optional] user-defined function context

    1288:   Level: beginner

    1290: .seealso: [](ch_ksp), `KSP`, `KSPSetComputeRHS()`, `SNESGetFunction()`, `KSPComputeInitialGuessFn`, `KSPComputeOperatorsFn`
    1291: S*/
    1292: PETSC_EXTERN_TYPEDEF typedef PetscErrorCode KSPComputeRHSFn(KSP ksp, Vec b, void *ctx);

    1294: PETSC_EXTERN PetscErrorCode KSPSetComputeRHS(KSP, KSPComputeRHSFn *, void *);

    1296: /*S
    1297:   KSPComputeOperatorsFn - A prototype of a `KSP` evaluation function that would be passed to `KSPSetComputeOperators()`

    1299:   Calling Sequence:
    1300: + ksp - `KSP` context
    1301: . A   - the operator that defines the linear system
    1302: . P   - an operator from which to build the preconditioner (often the same as `A`)
    1303: - ctx - [optional] user-defined function context

    1305:   Level: beginner

    1307: .seealso: [](ch_ksp), `KSP`, `KSPSetComputeRHS()`, `SNESGetFunction()`, `KSPComputeRHSFn`, `KSPComputeInitialGuessFn`
    1308: S*/
    1309: PETSC_EXTERN_TYPEDEF typedef PetscErrorCode KSPComputeOperatorsFn(KSP ksp, Mat A, Mat P, void *ctx);

    1311: PETSC_EXTERN PetscErrorCode KSPSetComputeOperators(KSP, KSPComputeOperatorsFn, void *);

    1313: /*S
    1314:   KSPComputeInitialGuessFn - A prototype of a `KSP` evaluation function that would be passed to `KSPSetComputeInitialGuess()`

    1316:   Calling Sequence:
    1317: + ksp  - `ksp` context
    1318: . x    - output vector
    1319: - ctx - [optional] user-defined function context

    1321:   Level: beginner

    1323: .seealso: [](ch_ksp), `KSP`, `KSPSetComputeInitialGuess()`, `SNESGetFunction()`, `KSPComputeRHSFn`, `KSPComputeOperatorsFn`
    1324: S*/
    1325: PETSC_EXTERN_TYPEDEF typedef PetscErrorCode KSPComputeInitialGuessFn(KSP ksp, Vec x, void *ctx);

    1327: PETSC_EXTERN PetscErrorCode KSPSetComputeInitialGuess(KSP, KSPComputeInitialGuessFn *, void *);
    1328: PETSC_EXTERN PetscErrorCode DMKSPSetComputeOperators(DM, KSPComputeOperatorsFn *, void *);
    1329: PETSC_EXTERN PetscErrorCode DMKSPGetComputeOperators(DM, KSPComputeOperatorsFn **, void *);
    1330: PETSC_EXTERN PetscErrorCode DMKSPSetComputeRHS(DM, KSPComputeRHSFn *, void *);
    1331: PETSC_EXTERN PetscErrorCode DMKSPGetComputeRHS(DM, KSPComputeRHSFn **, void *);
    1332: PETSC_EXTERN PetscErrorCode DMKSPSetComputeInitialGuess(DM, KSPComputeInitialGuessFn *, void *);
    1333: PETSC_EXTERN PetscErrorCode DMKSPGetComputeInitialGuess(DM, KSPComputeInitialGuessFn **, void *);

    1335: PETSC_EXTERN PetscErrorCode DMGlobalToLocalSolve(DM, Vec, Vec);
    1336: PETSC_EXTERN PetscErrorCode DMSwarmProjectFields(DM, DM, PetscInt, const char *[], Vec[], ScatterMode);
    1337: PETSC_EXTERN PetscErrorCode DMSwarmProjectGradientFields(DM, DM, PetscInt, const char *[], Vec[], ScatterMode);

    1339: PETSC_EXTERN PetscErrorCode DMAdaptInterpolator(DM, DM, Mat, KSP, Mat, Mat, Mat *, void *);
    1340: PETSC_EXTERN PetscErrorCode DMCheckInterpolator(DM, Mat, Mat, Mat, PetscReal);

    1342: PETSC_EXTERN PetscErrorCode PCBJKOKKOSSetKSP(PC, KSP);
    1343: PETSC_EXTERN PetscErrorCode PCBJKOKKOSGetKSP(PC, KSP *);

    1345: PETSC_EXTERN PetscErrorCode DMCopyDMKSP(DM, DM);

    1347: #include <petscdstypes.h>
    1348: PETSC_EXTERN PetscErrorCode DMProjectField(DM, PetscReal, Vec, PetscPointFn **, InsertMode, Vec);