Date: 2026-03-31T13:22:58+00:00

Actual source code: slepcst.h

      1: /*
      2:    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
      3:    SLEPc - Scalable Library for Eigenvalue Problem Computations
      4:    Copyright (c) 2002-, Universitat Politecnica de Valencia, Spain

      6:    This file is part of SLEPc.
      7:    SLEPc is distributed under a 2-clause BSD license (see LICENSE).
      8:    - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
      9: */
     10: /*
     11:    Spectral transformation module for eigenvalue problems
     12: */

     14: #pragma once

     16: #include <slepcsys.h>
     17: #include <slepcbv.h>
     18: #include <petscksp.h>

     20: /* SUBMANSEC = ST */

     22: SLEPC_EXTERN PetscErrorCode STInitializePackage(void);
     23: SLEPC_EXTERN PetscErrorCode STFinalizePackage(void);

     25: /*S
     26:    ST - Spectral transformation, encapsulates the functionality required
     27:    for acceleration techniques based on the transformation of the spectrum,
     28:    e.g., shift-and-invert.

     30:    Level: beginner

     32: .seealso: [](ch:st), `STCreate()`
     33: S*/
     34: typedef struct _p_ST* ST;

     36: /*J
     37:    STType - String with the name of the spectral transformation type.

     39:    Level: beginner

     41: .seealso: [](ch:st), `ST`, `STSetType()`
     42: J*/
     43: typedef const char *STType;
     44: #define STSHIFT     "shift"
     45: #define STSINVERT   "sinvert"
     46: #define STCAYLEY    "cayley"
     47: #define STPRECOND   "precond"
     48: #define STFILTER    "filter"
     49: #define STSHELL     "shell"

     51: /* Logging support */
     52: SLEPC_EXTERN PetscClassId ST_CLASSID;

     54: SLEPC_EXTERN PetscErrorCode STCreate(MPI_Comm,ST*);
     55: SLEPC_EXTERN PetscErrorCode STDestroy(ST*);
     56: SLEPC_EXTERN PetscErrorCode STReset(ST);
     57: SLEPC_EXTERN PetscErrorCode STSetType(ST,STType);
     58: SLEPC_EXTERN PetscErrorCode STGetType(ST,STType*);
     59: SLEPC_EXTERN PetscErrorCode STSetMatrices(ST,PetscInt,Mat[]);
     60: SLEPC_EXTERN PetscErrorCode STGetMatrix(ST,PetscInt,Mat*);
     61: SLEPC_EXTERN PetscErrorCode STGetMatrixTransformed(ST,PetscInt,Mat*);
     62: SLEPC_EXTERN PetscErrorCode STGetNumMatrices(ST,PetscInt*);
     63: SLEPC_EXTERN PetscErrorCode STGetOperator(ST,Mat*);
     64: SLEPC_EXTERN PetscErrorCode STRestoreOperator(ST,Mat*);
     65: SLEPC_EXTERN PetscErrorCode STSetUp(ST);
     66: SLEPC_EXTERN PetscErrorCode STSetFromOptions(ST);
     67: SLEPC_EXTERN PetscErrorCode STView(ST,PetscViewer);
     68: SLEPC_EXTERN PetscErrorCode STViewFromOptions(ST,PetscObject,const char[]);

     70: PETSC_DEPRECATED_FUNCTION(3, 15, 0, "STSetMatrices()", ) static inline PetscErrorCode STSetOperators(ST st,PetscInt n,Mat *A) {return STSetMatrices(st,n,A);}
     71: PETSC_DEPRECATED_FUNCTION(3, 15, 0, "STGetMatrix()", ) static inline PetscErrorCode STGetOperators(ST st,PetscInt k,Mat *A) {return STGetMatrix(st,k,A);}
     72: PETSC_DEPRECATED_FUNCTION(3, 15, 0, "STGetMatrixTransformed()", ) static inline PetscErrorCode STGetTOperators(ST st,PetscInt k,Mat *A) {return STGetMatrixTransformed(st,k,A);}
     73: PETSC_DEPRECATED_FUNCTION(3, 15, 0, "STGetOperator() followed by MatComputeOperator()", ) static inline PetscErrorCode STComputeExplicitOperator(ST st,Mat *A)
     74: {
     75:   Mat Op;

     77:   PetscFunctionBegin;
     78:   PetscCall(STGetOperator(st,&Op));
     79:   PetscCall(MatComputeOperator(Op,MATAIJ,A));
     80:   PetscCall(STRestoreOperator(st,&Op));
     81:   PetscFunctionReturn(PETSC_SUCCESS);
     82: }

     84: SLEPC_EXTERN PetscErrorCode STApply(ST,Vec,Vec);
     85: SLEPC_EXTERN PetscErrorCode STApplyMat(ST,Mat,Mat);
     86: SLEPC_EXTERN PetscErrorCode STApplyTranspose(ST,Vec,Vec);
     87: SLEPC_EXTERN PetscErrorCode STApplyHermitianTranspose(ST,Vec,Vec);
     88: SLEPC_EXTERN PetscErrorCode STMatMult(ST,PetscInt,Vec,Vec);
     89: SLEPC_EXTERN PetscErrorCode STMatMultTranspose(ST,PetscInt,Vec,Vec);
     90: SLEPC_EXTERN PetscErrorCode STMatMultHermitianTranspose(ST,PetscInt,Vec,Vec);
     91: SLEPC_EXTERN PetscErrorCode STMatSolve(ST,Vec,Vec);
     92: SLEPC_EXTERN PetscErrorCode STMatSolveTranspose(ST,Vec,Vec);
     93: SLEPC_EXTERN PetscErrorCode STMatSolveHermitianTranspose(ST,Vec,Vec);
     94: SLEPC_EXTERN PetscErrorCode STMatMatSolve(ST,Mat,Mat);
     95: SLEPC_EXTERN PetscErrorCode STGetBilinearForm(ST,Mat*);
     96: SLEPC_EXTERN PetscErrorCode STMatSetUp(ST,PetscScalar,PetscScalar[]);
     97: SLEPC_EXTERN PetscErrorCode STPostSolve(ST);
     98: SLEPC_EXTERN PetscErrorCode STResetMatrixState(ST);
     99: SLEPC_EXTERN PetscErrorCode STSetWorkVecs(ST,PetscInt);

    101: SLEPC_EXTERN PetscErrorCode STSetKSP(ST,KSP);
    102: SLEPC_EXTERN PetscErrorCode STGetKSP(ST,KSP*);
    103: SLEPC_EXTERN PetscErrorCode STSetShift(ST,PetscScalar);
    104: SLEPC_EXTERN PetscErrorCode STGetShift(ST,PetscScalar*);
    105: SLEPC_EXTERN PetscErrorCode STSetDefaultShift(ST,PetscScalar);
    106: SLEPC_EXTERN PetscErrorCode STScaleShift(ST,PetscScalar);
    107: SLEPC_EXTERN PetscErrorCode STSetBalanceMatrix(ST,Vec);
    108: SLEPC_EXTERN PetscErrorCode STGetBalanceMatrix(ST,Vec*);
    109: SLEPC_EXTERN PetscErrorCode STSetTransform(ST,PetscBool);
    110: SLEPC_EXTERN PetscErrorCode STGetTransform(ST,PetscBool*);
    111: SLEPC_EXTERN PetscErrorCode STSetStructured(ST,PetscBool);
    112: SLEPC_EXTERN PetscErrorCode STGetStructured(ST,PetscBool*);

    114: SLEPC_EXTERN PetscErrorCode STSetOptionsPrefix(ST,const char[]);
    115: SLEPC_EXTERN PetscErrorCode STAppendOptionsPrefix(ST,const char[]);
    116: SLEPC_EXTERN PetscErrorCode STGetOptionsPrefix(ST,const char*[]);

    118: SLEPC_EXTERN PetscErrorCode STBackTransform(ST,PetscInt,PetscScalar[],PetscScalar[]);
    119: SLEPC_EXTERN PetscErrorCode STIsInjective(ST,PetscBool*);

    121: SLEPC_EXTERN PetscErrorCode STCheckNullSpace(ST,BV);

    123: SLEPC_EXTERN PetscErrorCode STSetPreconditionerMat(ST,Mat);
    124: SLEPC_EXTERN PetscErrorCode STGetPreconditionerMat(ST,Mat*);
    125: SLEPC_EXTERN PetscErrorCode STSetSplitPreconditioner(ST,PetscInt,Mat[],MatStructure);
    126: SLEPC_EXTERN PetscErrorCode STGetSplitPreconditionerTerm(ST,PetscInt,Mat*);
    127: SLEPC_EXTERN PetscErrorCode STGetSplitPreconditionerInfo(ST,PetscInt*,MatStructure*);

    129: SLEPC_EXTERN PetscErrorCode STMatCreateVecs(ST,Vec*,Vec*);
    130: SLEPC_EXTERN PetscErrorCode STMatCreateVecsEmpty(ST,Vec*,Vec*);
    131: SLEPC_EXTERN PetscErrorCode STMatGetSize(ST,PetscInt*,PetscInt*);
    132: SLEPC_EXTERN PetscErrorCode STMatGetLocalSize(ST,PetscInt*,PetscInt*);

    134: /*E
    135:    STMatMode - Determines how to handle the coefficient matrix of the linear
    136:    system associated with the spectral transformation.

    138:    Values:
    139: +  `ST_MATMODE_COPY`    - the coefficient matrix is built explicitly on a copy of $A$
    140: .  `ST_MATMODE_INPLACE` - the coefficient matrix is built explicitly overwriting $A$
    141: -  `ST_MATMODE_SHELL`   - the coefficient matrix is handled implicitly

    143:    Level: intermediate

    145: .seealso: [](ch:st), `STSetMatMode()`, `STGetMatMode()`
    146: E*/
    147: typedef enum { ST_MATMODE_COPY,
    148:                ST_MATMODE_INPLACE,
    149:                ST_MATMODE_SHELL } STMatMode;
    150: SLEPC_EXTERN const char *STMatModes[];

    152: /*MC
    153:    ST_MATMODE_COPY - The coefficient matrix of the linear system, $A-\sigma B$, is
    154:    built explicitly on a copy of $A$.

    156:    Note:
    157:    If memory is an issue, one may prefer one of the other two modes.

    159:    Level: intermediate

    161: .seealso: [](ch:st), `STMatMode`, `STSetMatMode()`, `ST_MATMODE_INPLACE`, `ST_MATMODE_SHELL`
    162: M*/

    164: /*MC
    165:    ST_MATMODE_INPLACE - The coefficient matrix of the linear system, $A-\sigma B$, is
    166:    built explicitly overwritting $A$.

    168:    Note:
    169:    This mode uses less memory than `ST_MATMODE_COPY`, but it modifies $A$. This
    170:    alteration of $A$ is reversed after the eigensolution process has finished,
    171:    but due to roundoff, the result might not be exactly equal to the original $A$.

    173:    Level: intermediate

    175: .seealso: [](ch:st), `STMatMode`, `STSetMatMode()`, `ST_MATMODE_COPY`, `ST_MATMODE_SHELL`
    176: M*/

    178: /*MC
    179:    ST_MATMODE_SHELL - The coefficient matrix of the linear system, $A-\sigma B$, is
    180:    not built explicitly, and instead it is handled implicitly via a `MATSHELL`.

    182:    Note:
    183:    This mode severely restricts the number of possibilities available for solving
    184:    the linear system via `KSP`.

    186:    Level: intermediate

    188: .seealso: [](ch:st), `STMatMode`, `STSetMatMode()`, `ST_MATMODE_COPY`, `ST_MATMODE_INPLACE`
    189: M*/

    191: SLEPC_EXTERN PetscErrorCode STSetMatMode(ST,STMatMode);
    192: SLEPC_EXTERN PetscErrorCode STGetMatMode(ST,STMatMode*);
    193: SLEPC_EXTERN PetscErrorCode STSetMatStructure(ST,MatStructure);
    194: SLEPC_EXTERN PetscErrorCode STGetMatStructure(ST,MatStructure*);

    196: SLEPC_EXTERN PetscFunctionList STList;
    197: SLEPC_EXTERN PetscErrorCode STRegister(const char[],PetscErrorCode(*)(ST));

    199: /* --------- options specific to particular spectral transformations-------- */

    201: /*S
    202:    STShellDestroyFn - A prototype of a function for destroying the context
    203:    set with `STShellSetContext()` in an `STSHELL`.

    205:    Calling Sequence:
    206: .  st   - the spectral transformation context

    208:    Level: advanced

    210: .seealso: [](ch:st), `STShellSetDestroy()`, `STShellSetContext()`
    211: S*/
    212: PETSC_EXTERN_TYPEDEF typedef PetscErrorCode STShellDestroyFn(ST st);

    214: /*S
    215:    STShellApplyFn - A prototype of a function for the user-defined `STApply()`
    216:    operation in an `STSHELL`.

    218:    Calling Sequence:
    219: +  st   - the spectral transformation context
    220: .  xin  - input vector
    221: -  xout - output vector

    223:    Level: advanced

    225: .seealso: [](ch:st), `STShellSetApply()`, `STApply()`
    226: S*/
    227: PETSC_EXTERN_TYPEDEF typedef PetscErrorCode STShellApplyFn(ST st,Vec xin,Vec xout);

    229: /*S
    230:    STShellApplyTransposeFn - A prototype of a function for the user-defined `STApplyTranspose()`
    231:    operation in an `STSHELL`.

    233:    Calling Sequence:
    234: +  st   - the spectral transformation context
    235: .  xin  - input vector
    236: -  xout - output vector

    238:    Level: advanced

    240: .seealso: [](ch:st), `STShellSetApplyTranspose()`, `STApplyTranspose()`
    241: S*/
    242: PETSC_EXTERN_TYPEDEF typedef PetscErrorCode STShellApplyTransposeFn(ST st,Vec xin,Vec xout);

    244: /*S
    245:    STShellApplyHermitianTransposeFn - A prototype of a function for the user-defined
    246:    `STApplyHermitianTranspose()` operation in an `STSHELL`.

    248:    Calling Sequence:
    249: +  st   - the spectral transformation context
    250: .  xin  - input vector
    251: -  xout - output vector

    253:    Level: advanced

    255: .seealso: [](ch:st), `STShellSetApplyHermitianTranspose()`, `STApplyHermitianTranspose()`
    256: S*/
    257: PETSC_EXTERN_TYPEDEF typedef PetscErrorCode STShellApplyHermitianTransposeFn(ST st,Vec xin,Vec xout);

    259: /*S
    260:    STShellBackTransformFn - A prototype of a function for the user-defined `STBackTransform()`
    261:    operation in an `STSHELL`.

    263:    Calling Sequence:
    264: +  st   - the spectral transformation context
    265: .  n    - number of eigenvalues to be backtransformed
    266: .  eigr - pointer to the real parts of the eigenvalues to transform back
    267: -  eigi - pointer to the imaginary parts

    269:    Level: advanced

    271: .seealso: [](ch:st), `STShellSetBackTransform()`, `STBackTransform()`
    272: S*/
    273: PETSC_EXTERN_TYPEDEF typedef PetscErrorCode STShellBackTransformFn(ST st,PetscInt n,PetscScalar *eigr,PetscScalar *eigi);

    275: SLEPC_EXTERN PetscErrorCode STShellGetContext(ST,PetscCtxRt);
    276: SLEPC_EXTERN PetscErrorCode STShellSetContext(ST,PetscCtx);
    277: SLEPC_EXTERN PetscErrorCode STShellSetDestroy(ST,STShellDestroyFn*);
    278: SLEPC_EXTERN PetscErrorCode STShellSetApply(ST,STShellApplyFn*);
    279: SLEPC_EXTERN PetscErrorCode STShellSetApplyTranspose(ST,STShellApplyTransposeFn*);
    280: SLEPC_EXTERN PetscErrorCode STShellSetApplyHermitianTranspose(ST,STShellApplyHermitianTransposeFn*);
    281: SLEPC_EXTERN PetscErrorCode STShellSetBackTransform(ST,STShellBackTransformFn*);

    283: SLEPC_EXTERN PetscErrorCode STCayleyGetAntishift(ST,PetscScalar*);
    284: SLEPC_EXTERN PetscErrorCode STCayleySetAntishift(ST,PetscScalar);

    286: PETSC_DEPRECATED_FUNCTION(3, 15, 0, "STGetPreconditionerMat()", ) static inline PetscErrorCode STPrecondGetMatForPC(ST st,Mat *A) {return STGetPreconditionerMat(st,A);}
    287: PETSC_DEPRECATED_FUNCTION(3, 15, 0, "STSetPreconditionerMat()", ) static inline PetscErrorCode STPrecondSetMatForPC(ST st,Mat A) {return STSetPreconditionerMat(st,A);}
    288: SLEPC_EXTERN PetscErrorCode STPrecondGetKSPHasMat(ST,PetscBool*);
    289: SLEPC_EXTERN PetscErrorCode STPrecondSetKSPHasMat(ST,PetscBool);

    291: /*E
    292:    STFilterType - Selects the method used to build the filter.

    294:    Values:
    295: +  `ST_FILTER_FILTLAN`   - the filter is built with FILTLAN (Filtered Lanczos)
    296: -  `ST_FILTER_CHEBYSHEV` - the filter is built with a Chebyshev series

    298:    Level: intermediate

    300: .seealso: [](ch:st), `STFilterSetType()`, `STGetFilterType()`
    301: E*/
    302: typedef enum { ST_FILTER_FILTLAN   = 1,
    303:                ST_FILTER_CHEBYSHEV = 2 } STFilterType;
    304: SLEPC_EXTERN const char *STFilterTypes[];

    306: /*MC
    307:    ST_FILTER_FILTLAN - The polynomial filter is built with FILTLAN (Filtered Lanczos).

    309:    Note:
    310:    This filter implements the Filtered Lanczos method {cite:p}`Fan12`. In fact,
    311:    the implementation adapts files from the FILTLAN package by the same authors,
    312:    which have been converted for a native integration in SLEPc.

    314:    Level: intermediate

    316: .seealso: [](ch:st), `STFilterType`, `STFilterSetType()`, `ST_FILTER_CHEBYSHEV`
    317: M*/

    319: /*MC
    320:    ST_FILTER_CHEBYSHEV - The filter is based on a truncated Chebyshev series.

    322:    Note:
    323:    The application of the filter is implemented by means of a Clenshaw
    324:    algorithm. This filter also supports using damping, see `STFilterSetDamping()`.

    326:    Level: intermediate

    328: .seealso: [](ch:st), `STFilterType`, `STSetFilterType()`, `STFilterSetDamping()`, `ST_FILTER_FILTLAN`
    329: M*/

    331: /*E
    332:    STFilterDamping - The damping type used to build the filter.

    334:    Values:
    335: +  `ST_FILTER_DAMPING_NONE`    - no damping
    336: .  `ST_FILTER_DAMPING_JACKSON` - Jackson damping
    337: .  `ST_FILTER_DAMPING_LANCZOS` - Lanczos damping
    338: -  `ST_FILTER_DAMPING_FEJER`   - Fejer damping

    340:    Notes:
    341:    The default is no damping.

    343:    For the definition of the damping coefficients, see for instance {cite:p}`Pie16`

    345:    Level: advanced

    347: .seealso: [](ch:st), `STSetFilterDamping()`, `STGetFilterDamping()`
    348: E*/
    349: typedef enum { ST_FILTER_DAMPING_NONE,
    350:                ST_FILTER_DAMPING_JACKSON,
    351:                ST_FILTER_DAMPING_LANCZOS,
    352:                ST_FILTER_DAMPING_FEJER } STFilterDamping;
    353: SLEPC_EXTERN const char *STFilterDampings[];

    355: /*MC
    356:    ST_MATMODE_COPY - The coefficient matrix of the linear system, $A-\sigma B$, is
    357:    built explicitly on a copy of $A$.

    359:    Note:
    360:    If memory is an issue, one may prefer one of the other two modes.

    362:    Level: intermediate

    364: .seealso: [](ch:st), `STMatMode`, `STSetMatMode()`, `ST_MATMODE_INPLACE`, `ST_MATMODE_SHELL`
    365: M*/

    367: SLEPC_EXTERN PetscErrorCode STFilterSetType(ST,STFilterType);
    368: SLEPC_EXTERN PetscErrorCode STFilterGetType(ST,STFilterType*);
    369: SLEPC_EXTERN PetscErrorCode STFilterSetInterval(ST,PetscReal,PetscReal);
    370: SLEPC_EXTERN PetscErrorCode STFilterGetInterval(ST,PetscReal*,PetscReal*);
    371: SLEPC_EXTERN PetscErrorCode STFilterSetRange(ST,PetscReal,PetscReal);
    372: SLEPC_EXTERN PetscErrorCode STFilterGetRange(ST,PetscReal*,PetscReal*);
    373: SLEPC_EXTERN PetscErrorCode STFilterSetDegree(ST,PetscInt);
    374: SLEPC_EXTERN PetscErrorCode STFilterGetDegree(ST,PetscInt*);
    375: SLEPC_EXTERN PetscErrorCode STFilterGetThreshold(ST,PetscReal*);
    376: SLEPC_EXTERN PetscErrorCode STFilterSetDamping(ST,STFilterDamping);
    377: SLEPC_EXTERN PetscErrorCode STFilterGetDamping(ST,STFilterDamping*);