Date: 2026-03-31T13:23:00+00:00

Actual source code: mfnimpl.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: */

     11: #pragma once

     13: #include <slepcmfn.h>
     14: #include <slepc/private/slepcimpl.h>

     16: /* SUBMANSEC = MFN */

     18: SLEPC_EXTERN PetscBool MFNRegisterAllCalled;
     19: SLEPC_EXTERN PetscBool MFNMonitorRegisterAllCalled;
     20: SLEPC_EXTERN PetscErrorCode MFNRegisterAll(void);
     21: SLEPC_EXTERN PetscErrorCode MFNMonitorRegisterAll(void);
     22: SLEPC_EXTERN PetscLogEvent MFN_SetUp,MFN_Solve;

     24: typedef struct _MFNOps *MFNOps;

     26: struct _MFNOps {
     27:   PetscErrorCode (*solve)(MFN,Vec,Vec);
     28:   PetscErrorCode (*setup)(MFN);
     29:   PetscErrorCode (*setfromoptions)(MFN,PetscOptionItems);
     30:   PetscErrorCode (*publishoptions)(MFN);
     31:   PetscErrorCode (*destroy)(MFN);
     32:   PetscErrorCode (*reset)(MFN);
     33:   PetscErrorCode (*view)(MFN,PetscViewer);
     34: };

     36: /*
     37:      Maximum number of monitors you can run with a single MFN
     38: */
     39: #define MAXMFNMONITORS 5

     41: /*
     42:    Defines the MFN data structure.
     43: */
     44: struct _p_MFN {
     45:   PETSCHEADER(struct _MFNOps);
     46:   /*------------------------- User parameters ---------------------------*/
     47:   Mat            A;                /* the problem matrix */
     48:   FN             fn;               /* which function to compute */
     49:   PetscInt       max_it;           /* maximum number of iterations */
     50:   PetscInt       ncv;              /* number of basis vectors */
     51:   PetscReal      tol;              /* tolerance */
     52:   PetscBool      errorifnotconverged;    /* error out if MFNSolve() does not converge */

     54:   /*-------------- User-provided functions and contexts -----------------*/
     55:   MFNMonitorFn      *monitor[MAXMFNMONITORS];
     56:   PetscCtxDestroyFn *monitordestroy[MAXMFNMONITORS];
     57:   void              *monitorcontext[MAXMFNMONITORS];
     58:   PetscInt          numbermonitors;

     60:   /*----------------- Child objects and working data -------------------*/
     61:   BV             V;                /* set of basis vectors */
     62:   Mat            AT;               /* the transpose of A, used in MFNSolveTranspose */
     63:   PetscInt       nwork;            /* number of work vectors */
     64:   Vec            *work;            /* work vectors */
     65:   void           *data;            /* placeholder for solver-specific stuff */

     67:   /* ----------------------- Status variables -------------------------- */
     68:   PetscInt       its;              /* number of iterations so far computed */
     69:   PetscInt       nv;               /* size of current Schur decomposition */
     70:   PetscReal      errest;           /* error estimate */
     71:   PetscReal      bnorm;            /* computed norm of right-hand side in current solve */
     72:   PetscBool      transpose_solve;  /* solve transpose system instead */
     73:   PetscInt       setupcalled;
     74:   MFNConvergedReason reason;
     75: };

     77: /*
     78:    MFN_CreateDenseMat - Creates a dense Mat of size k unless it already has that size
     79: */
     80: static inline PetscErrorCode MFN_CreateDenseMat(PetscInt k,Mat *A)
     81: {
     82:   PetscBool      create=PETSC_FALSE;
     83:   PetscInt       m,n;

     85:   PetscFunctionBegin;
     86:   if (!*A) create=PETSC_TRUE;
     87:   else {
     88:     PetscCall(MatGetSize(*A,&m,&n));
     89:     if (m!=k || n!=k) {
     90:       PetscCall(MatDestroy(A));
     91:       create=PETSC_TRUE;
     92:     }
     93:   }
     94:   if (create) PetscCall(MatCreateSeqDense(PETSC_COMM_SELF,k,k,NULL,A));
     95:   PetscFunctionReturn(PETSC_SUCCESS);
     96: }

     98: /*
     99:    MFN_CreateVec - Creates a Vec of size k unless it already has that size
    100: */
    101: static inline PetscErrorCode MFN_CreateVec(PetscInt k,Vec *v)
    102: {
    103:   PetscBool      create=PETSC_FALSE;
    104:   PetscInt       n;

    106:   PetscFunctionBegin;
    107:   if (!*v) create=PETSC_TRUE;
    108:   else {
    109:     PetscCall(VecGetSize(*v,&n));
    110:     if (n!=k) {
    111:       PetscCall(VecDestroy(v));
    112:       create=PETSC_TRUE;
    113:     }
    114:   }
    115:   if (create) PetscCall(VecCreateSeq(PETSC_COMM_SELF,k,v));
    116:   PetscFunctionReturn(PETSC_SUCCESS);
    117: }