Date: 2022-03-31T04:48:10+00:00

Actual source code: lgmresimpl.h

      1: /* A. Baker */
      2: /*
      3:    Private data structure used by the LGMRES method.
      4: */

      9: #define KSPGMRES_NO_MACROS
     10: #include <../src/ksp/ksp/impls/gmres/gmresimpl.h>

     12: typedef struct {
     13:   KSPGMRESHEADER

     15:   /* LGMRES_MOD - make these for the z vectors - new storage for lgmres */
     16:   Vec *augvecs;                      /* holds the error approximation vectors for lgmres. */
     17:   Vec **augvecs_user_work;           /* same purpose as user_work above, but this one is
     18:                                          for our error approx vectors */
     19:   /* currently only augvecs_user_work[0] is used, not sure if this will be */
     20:   /* extended in the future to use more, or if this is a design bug */
     21:   PetscInt aug_vv_allocated;           /* aug_vv_allocated is the number of allocated lgmres
     22:                                           augmentation vectors */
     23:   PetscInt aug_vecs_allocated;         /* aug_vecs_allocated is the total number of augmentation vecs
     24:                                           available - used to simplify the dynamic
     25:                                        allocation of vectors */
     26:   PetscScalar *hwork;                /* work array to hold Hessenberg product */

     28:   PetscInt augwork_alloc;            /*size of chunk allocated for augmentation vectors */

     30:   PetscInt aug_dim;                  /* max number of augmented directions to add */

     32:   PetscInt aug_ct;                   /* number of aug. vectors available */

     34:   PetscInt *aug_order;               /*keeps track of order to use aug. vectors*/

     36:   PetscBool approx_constant;        /* = 1 then the approx space at each restart will
     37:                                   be  size max_k .  Therefore, more than (max_k - aug_dim)
     38:                                   krylov vectors may be used if less than aug_dim error
     39:                                   approximations are available (in the first few restarts,
     40:                                   for example) to keep the space a constant size. */

     42:   PetscInt matvecs;                 /*keep track of matvecs */
     43: } KSP_LGMRES;

     45: #define HH(a,b)  (lgmres->hh_origin + (b)*(lgmres->max_k+2)+(a))
     46: /* HH will be size (max_k+2)*(max_k+1)  -  think of HH as
     47:    being stored columnwise (inc. zeros) for access purposes. */
     48: #define HES(a,b) (lgmres->hes_origin + (b)*(lgmres->max_k+1)+(a))
     49: /* HES will be size (max_k + 1) * (max_k + 1) -
     50:    again, think of HES as being stored columnwise */
     51: #define CC(a)    (lgmres->cc_origin + (a)) /* CC will be length (max_k+1) - cosines */
     52: #define SS(a)    (lgmres->ss_origin + (a)) /* SS will be length (max_k+1) - sines */
     53: #define GRS(a)    (lgmres->rs_origin + (a)) /* GRS will be length (max_k+2) - rt side */

     55: /* vector names */
     56: #define VEC_OFFSET     2
     57: #define VEC_TEMP       lgmres->vecs[0]               /* work space */
     58: #define VEC_TEMP_MATOP lgmres->vecs[1]               /* work space */
     59: #define VEC_VV(i)      lgmres->vecs[VEC_OFFSET+i]    /* use to access
     60:                                                         othog basis vectors */
     61: /*LGMRES_MOD */
     62: #define AUG_OFFSET     1
     63: #define AUGVEC(i)      lgmres->augvecs[AUG_OFFSET+i]   /*error approx vectors */
     64: #define AUG_ORDER(i)   lgmres->aug_order[i]            /*order in which to augment */
     65: #define A_AUGVEC(i)    lgmres->augvecs[AUG_OFFSET+i+lgmres->aug_dim] /*A times error vector */
     66: #define AUG_TEMP       lgmres->augvecs[0]              /* work vector */
     67: #endif