Date: 2026-06-01T23:13:25+00:00

Actual source code: gmresimpl.h

      1: /*
      2:    Private data structure used by the GMRES method. This data structure
      3:   must be identical to the beginning of the KSP_FGMRES data structure
      4:   so if you CHANGE anything here you must also change it there.
      5: */
      6: #pragma once

      8: #include <petsc/private/kspimpl.h>

     10: #define KSPGMRESHEADER \
     11:   /* Hessenberg matrix and orthogonalization information. */ \
     12:   PetscScalar *hh_origin;  /* holds Hessenberg matrix that has been multiplied by plane rotations (upper tri) */ \
     13:   PetscScalar *hes_origin; /* holds the original (unmodified) Hessenberg matrix which may be used to estimate the Singular Values of the matrix */ \
     14:   PetscScalar *hes_ritz;   /* holds the last full Hessenberg matrix to compute (harmonic) Ritz pairs */ \
     15:   PetscScalar *cc_origin;  /* holds cosines for rotation matrices */ \
     16:   PetscScalar *ss_origin;  /* holds sines for rotation matrices */ \
     17:   PetscScalar *rs_origin;  /* holds the right-hand side of the Hessenberg system */ \
     18: \
     19:   PetscScalar *orthogwork; /* holds dot products computed in orthogonalization */ \
     20: \
     21:   /* Work space for computing eigenvalues/singular values */ \
     22:   PetscReal   *Dsvd; \
     23:   PetscScalar *Rsvd; \
     24: \
     25:   PetscReal haptol;      /* tolerance for happy breakdown */ \
     26:   PetscInt  max_k;       /* number of vectors in Krylov space, restart size */ \
     27:   PetscInt  nextra_vecs; /* number of extra vecs needed, e.g. for a pipeline */ \
     28: \
     29:   PetscErrorCode (*orthog)(KSP, PetscInt); \
     30:   KSPGMRESCGSRefinementType cgstype; \
     31: \
     32:   Vec      *vecs;           /* the work vectors */ \
     33:   Vec      *vecb;           /* holds the last full basis vectors of the Krylov subspace to compute (harmonic) Ritz pairs */ \
     34:   PetscBool q_preallocate;  /* Preallocate all the work vectors for the Krylov subspace */ \
     35:   PetscInt  delta_allocate; /* number of vectors to preallocaate in each block if not preallocated */ \
     36:   PetscInt  vv_allocated;   /* number of allocated gmres direction vectors */ \
     37:   PetscInt  vecs_allocated; /*   total number of vecs available */ \
     38:   /* Since we may call the user "obtain_work_vectors" several times, we have to keep track of the pointers that it has returned */ \
     39:   Vec     **user_work; \
     40:   PetscInt *mwork_alloc; /* Number of work vectors allocated as part of  a work-vector chunk */ \
     41:   PetscInt  nwork_alloc; /* Number of work vector chunks allocated */ \
     42: \
     43:   /* Information for building solution */ \
     44:   PetscInt     it;           /* Current iteration: inside restart */ \
     45:   PetscInt     fullcycle;    /* Current number of complete cycle */ \
     46:   PetscScalar *nrs;          /* temp that holds the coefficients of the Krylov vectors that form the minimum residual solution */ \
     47:   Vec          sol_temp;     /* used to hold temporary solution */ \
     48:   PetscReal    rnorm0;       /* residual norm at beginning of the GMRESCycle */ \
     49:   PetscReal    breakdowntol; /* A relative tolerance is used for breakdown check in GMRESCycle */

     51: typedef struct {
     52:   KSPGMRESHEADER
     53: } KSP_GMRES;

     55: PETSC_INTERN PetscErrorCode KSPView_GMRES(KSP, PetscViewer);
     56: PETSC_INTERN PetscErrorCode KSPSetUp_GMRES(KSP);
     57: PETSC_INTERN PetscErrorCode KSPSetFromOptions_GMRES(KSP, PetscOptionItems PetscOptionsObject);
     58: PETSC_INTERN PetscErrorCode KSPComputeExtremeSingularValues_GMRES(KSP, PetscReal *, PetscReal *);
     59: PETSC_INTERN PetscErrorCode KSPComputeEigenvalues_GMRES(KSP, PetscInt, PetscReal *, PetscReal *, PetscInt *);
     60: PETSC_INTERN PetscErrorCode KSPComputeRitz_GMRES(KSP, PetscBool, PetscBool, PetscInt *, Vec[], PetscReal *, PetscReal *);
     61: PETSC_INTERN PetscErrorCode KSPReset_GMRES(KSP);
     62: PETSC_INTERN PetscErrorCode KSPDestroy_GMRES(KSP);
     63: PETSC_INTERN PetscErrorCode KSPGMRESGetNewVectors(KSP, PetscInt);

     65: typedef PetscErrorCode (*FCN)(KSP, PetscInt); /* force argument to next function to not be extern C*/

     67: PETSC_INTERN PetscErrorCode KSPGMRESSetHapTol_GMRES(KSP, PetscReal);
     68: PETSC_INTERN PetscErrorCode KSPGMRESSetPreAllocateVectors_GMRES(KSP);
     69: PETSC_INTERN PetscErrorCode KSPGMRESSetRestart_GMRES(KSP, PetscInt);
     70: PETSC_INTERN PetscErrorCode KSPGMRESGetRestart_GMRES(KSP, PetscInt *);
     71: PETSC_INTERN PetscErrorCode KSPGMRESSetOrthogonalization_GMRES(KSP, FCN);
     72: PETSC_INTERN PetscErrorCode KSPGMRESGetOrthogonalization_GMRES(KSP, FCN *);
     73: PETSC_INTERN PetscErrorCode KSPGMRESSetCGSRefinementType_GMRES(KSP, KSPGMRESCGSRefinementType);
     74: PETSC_INTERN PetscErrorCode KSPGMRESGetCGSRefinementType_GMRES(KSP, KSPGMRESCGSRefinementType *);

     76: /* These macros are guarded because they are redefined by derived implementations */
     77: #if !defined(KSPGMRES_NO_MACROS)
     78:   #define HH(a, b)  (gmres->hh_origin + (b) * (gmres->max_k + 2) + (a))
     79:   #define HES(a, b) (gmres->hes_origin + (b) * (gmres->max_k + 1) + (a))
     80:   #define CC(a)     (gmres->cc_origin + (a))
     81:   #define SS(a)     (gmres->ss_origin + (a))
     82:   #define GRS(a)    (gmres->rs_origin + (a))

     84:   /* vector names */
     85:   #define VEC_OFFSET     2
     86:   #define VEC_TEMP       gmres->vecs[0]
     87:   #define VEC_TEMP_MATOP gmres->vecs[1]
     88:   #define VEC_VV(i)      gmres->vecs[VEC_OFFSET + i]
     89: #endif