Actual source code: snesimpl.h

      2: #ifndef __SNESIMPL_H

     5:  #include petscsnes.h

      7: typedef struct _SNESOps *SNESOps;

      9: struct _SNESOps {
     10:   PetscErrorCode (*computefunction)(SNES,Vec,Vec,void*);
     11:   PetscErrorCode (*computejacobian)(SNES,Vec,Mat*,Mat*,MatStructure*,void*);
     12:   PetscErrorCode (*computescaling)(Vec,Vec,void*);
     13:   PetscErrorCode (*update)(SNES, PetscInt);                     /* General purpose function for update */
     14:   PetscErrorCode (*converged)(SNES,PetscInt,PetscReal,PetscReal,PetscReal,SNESConvergedReason*,void*);
     15:   PetscErrorCode (*setup)(SNES);             /* routine to set up the nonlinear solver */
     16:   PetscErrorCode (*solve)(SNES);             /* actual nonlinear solver */
     17:   PetscErrorCode (*view)(SNES,PetscViewer);
     18:   PetscErrorCode (*setfromoptions)(SNES);    /* sets options from database */
     19:   PetscErrorCode (*destroy)(SNES);
     20: };

     22: /*
     23:    Nonlinear solver context
     24:  */
     25: #define MAXSNESMONITORS 5

     27: struct _p_SNES {
     28:   PETSCHEADER(struct _SNESOps);

     30:   /*  ------------------------ User-provided stuff -------------------------------*/
     31:   void  *user;                                        /* user-defined context */

     33:   Vec   vec_sol,vec_sol_always;                 /* pointer to solution */
     34:   Vec   vec_sol_update_always;                  /* pointer to solution update */

     36:   Vec            vec_func,vec_func_always;               /* pointer to function */
     37:   Vec            afine;                                  /* If non-null solve F(x) = afine */
     38:   void           *funP;                                  /* user-defined function context */

     41:   Mat            jacobian;                               /* Jacobian matrix */
     42:   Mat            jacobian_pre;                           /* preconditioner matrix */
     43:   void           *jacP;                                  /* user-defined Jacobian context */
     44:   KSP            ksp;                                   /* linear solver context */

     46:   Vec            scaling;                                /* scaling vector */
     47:   void           *scaP;                                  /* scaling context */

     49:   /* ------------------------Time stepping hooks-----------------------------------*/

     51:   /* ---------------- PETSc-provided (or user-provided) stuff ---------------------*/

     53:   PetscErrorCode (*monitor[MAXSNESMONITORS])(SNES,PetscInt,PetscReal,void*); /* monitor routine */
     54:   PetscErrorCode (*monitordestroy[MAXSNESMONITORS])(void*);          /* monitor context destroy routine */
     55:   void           *monitorcontext[MAXSNESMONITORS];                   /* monitor context */
     56:   PetscInt       numbermonitors;                                     /* number of monitors */
     57:   void           *cnvP;                                                    /* convergence context */
     58:   SNESConvergedReason reason;

     60:   /* --- Routines and data that are unique to each particular solver --- */

     62:   PetscTruth     setupcalled;                /* true if setup has been called */
     63:   void           *data;                      /* implementation-specific data */

     65:   /* --------------------------  Parameters -------------------------------------- */

     67:   PetscInt    max_its;            /* max number of iterations */
     68:   PetscInt    max_funcs;          /* max number of function evals */
     69:   PetscInt    nfuncs;             /* number of function evaluations */
     70:   PetscInt    iter;               /* global iteration number */
     71:   PetscInt    linear_its;         /* total number of linear solver iterations */
     72:   PetscReal   norm;            /* residual norm of current iterate */
     73:   PetscReal   rtol;            /* relative tolerance */
     74:   PetscReal   abstol;            /* absolute tolerance */
     75:   PetscReal   xtol;            /* relative tolerance in solution */
     76:   PetscReal   deltatol;        /* trust region convergence tolerance */
     77:   PetscTruth  printreason;     /* print reason for convergence/divergence after each solve */
     78:   /* ------------------------ Default work-area management ---------------------- */

     80:   PetscInt    nwork;
     81:   Vec         *work;

     83:   /* ------------------------- Miscellaneous Information ------------------------ */

     85:   PetscReal   *conv_hist;         /* If !0, stores function norm (or
     86:                                     gradient norm) at each iteration */
     87:   PetscInt    *conv_hist_its;     /* linear iterations for each Newton step */
     88:   PetscInt    conv_hist_len;      /* size of convergence history array */
     89:   PetscInt    conv_hist_max;      /* actual amount of data in conv_history */
     90:   PetscTruth  conv_hist_reset;    /* reset counter for each new SNES solve */

     92:   /* the next two are used for failures in the line search; they should be put into the LS struct */
     93:   PetscInt    numFailures;        /* number of unsuccessful step attempts */
     94:   PetscInt    maxFailures;        /* maximum number of unsuccessful step attempts */

     96:   PetscInt    numLinearSolveFailures;
     97:   PetscInt    maxLinearSolveFailures;

     99:  /*
    100:    These are REALLY ugly and don't belong here, but since they must
    101:   be destroyed at the conclusion we have to put them somewhere.
    102:  */
    103:   PetscTruth  ksp_ewconv;        /* flag indicating use of Eisenstat-Walker KSP convergence criteria */
    104:   void        *kspconvctx;       /* KSP convergence context */

    106:   PetscReal   ttol;           /* used by default convergence test routine */

    108:   Vec         *vwork;            /* more work vectors for Jacobian approx */
    109:   PetscInt    nvwork;
    110: };

    112: /* Context for Eisenstat-Walker convergence criteria for KSP solvers */
    113: typedef struct {
    114:   PetscInt  version;             /* flag indicating version 1 or 2 of test */
    115:   PetscReal rtol_0;              /* initial rtol */
    116:   PetscReal rtol_last;           /* last rtol */
    117:   PetscReal rtol_max;            /* maximum rtol */
    118:   PetscReal gamma;               /* mult. factor for version 2 rtol computation */
    119:   PetscReal alpha;               /* power for version 2 rtol computation */
    120:   PetscReal alpha2;              /* power for safeguard */
    121:   PetscReal threshold;           /* threshold for imposing safeguard */
    122:   PetscReal lresid_last;         /* linear residual from last iteration */
    123:   PetscReal norm_last;           /* function norm from last iteration */
    124: } SNESKSPEW;

    126: #define SNESLogConvHistory(snes,res,its) \
    127:   { if (snes->conv_hist && snes->conv_hist_max > snes->conv_hist_len) \
    128:     { if (snes->conv_hist)     snes->conv_hist[snes->conv_hist_len]     = res; \
    129:       if (snes->conv_hist_its) snes->conv_hist_its[snes->conv_hist_len] = its; \
    130:       snes->conv_hist_len++;\
    131:     }}

    133: #define SNESMonitor(snes,it,rnorm) \
    134:         { PetscErrorCode _ierr; PetscInt _i,_im = snes->numbermonitors; \
    135:           for (_i=0; _i<_im; _i++) {\
    136:             _(*snes->monitor[_i])(snes,it,rnorm,snes->monitorcontext[_i]);CHKERRQ(_ierr); \
    137:           } \
    138:         }

    140: PetscErrorCode SNES_KSPSolve(SNES,KSP,Vec,Vec);
    141: PetscErrorCode SNESScaleStep_Private(SNES,Vec,PetscReal*,PetscReal*,PetscReal*,PetscReal*);

    145: #endif