Actual source code: fdmatrix.c
petsc-3.10.5 2019-03-28
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      2: /*
      3:    This is where the abstract matrix operations are defined that are
      4:   used for finite difference computations of Jacobians using coloring.
      5: */

      7:  #include <petsc/private/matimpl.h>
      8:  #include <petsc/private/isimpl.h>

     10: PetscErrorCode  MatFDColoringSetF(MatFDColoring fd,Vec F)
     11: {

     15:   if (F) {
     16:     VecCopy(F,fd->w1);
     17:     fd->fset = PETSC_TRUE;
     18:   } else {
     19:     fd->fset = PETSC_FALSE;
     20:   }
     21:   return(0);
     22: }

     24:  #include <petscdraw.h>
     25: static PetscErrorCode MatFDColoringView_Draw_Zoom(PetscDraw draw,void *Aa)
     26: {
     27:   MatFDColoring  fd = (MatFDColoring)Aa;
     29:   PetscInt       i,j,nz,row;
     30:   PetscReal      x,y;
     31:   MatEntry       *Jentry=fd->matentry;

     34:   /* loop over colors  */
     35:   nz = 0;
     36:   for (i=0; i<fd->ncolors; i++) {
     37:     for (j=0; j<fd->nrows[i]; j++) {
     38:       row = Jentry[nz].row;
     39:       y   = fd->M - row - fd->rstart;
     40:       x   = (PetscReal)Jentry[nz++].col;
     41:       PetscDrawRectangle(draw,x,y,x+1,y+1,i+1,i+1,i+1,i+1);
     42:     }
     43:   }
     44:   return(0);
     45: }

     47: static PetscErrorCode MatFDColoringView_Draw(MatFDColoring fd,PetscViewer viewer)
     48: {
     50:   PetscBool      isnull;
     51:   PetscDraw      draw;
     52:   PetscReal      xr,yr,xl,yl,h,w;

     55:   PetscViewerDrawGetDraw(viewer,0,&draw);
     56:   PetscDrawIsNull(draw,&isnull);
     57:   if (isnull) return(0);

     59:   xr   = fd->N; yr  = fd->M; h = yr/10.0; w = xr/10.0;
     60:   xr  += w;     yr += h;    xl = -w;     yl = -h;
     61:   PetscDrawSetCoordinates(draw,xl,yl,xr,yr);
     62:   PetscObjectCompose((PetscObject)fd,"Zoomviewer",(PetscObject)viewer);
     63:   PetscDrawZoom(draw,MatFDColoringView_Draw_Zoom,fd);
     64:   PetscObjectCompose((PetscObject)fd,"Zoomviewer",NULL);
     65:   PetscDrawSave(draw);
     66:   return(0);
     67: }

     69: /*@C
     70:    MatFDColoringView - Views a finite difference coloring context.

     72:    Collective on MatFDColoring

     74:    Input  Parameters:
     75: +  c - the coloring context
     76: -  viewer - visualization context

     78:    Level: intermediate

     80:    Notes:
     81:    The available visualization contexts include
     82: +     PETSC_VIEWER_STDOUT_SELF - standard output (default)
     83: .     PETSC_VIEWER_STDOUT_WORLD - synchronized standard
     84:         output where only the first processor opens
     85:         the file.  All other processors send their
     86:         data to the first processor to print.
     87: -     PETSC_VIEWER_DRAW_WORLD - graphical display of nonzero structure

     89:    Notes:
     90:      Since PETSc uses only a small number of basic colors (currently 33), if the coloring
     91:    involves more than 33 then some seemingly identical colors are displayed making it look
     92:    like an illegal coloring. This is just a graphical artifact.

     94: .seealso: MatFDColoringCreate()

     96: .keywords: Mat, finite differences, coloring, view
     97: @*/
     98: PetscErrorCode  MatFDColoringView(MatFDColoring c,PetscViewer viewer)
     99: {
    100:   PetscErrorCode    ierr;
    101:   PetscInt          i,j;
    102:   PetscBool         isdraw,iascii;
    103:   PetscViewerFormat format;

    107:   if (!viewer) {
    108:     PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)c),&viewer);
    109:   }

    113:   PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERDRAW,&isdraw);
    114:   PetscObjectTypeCompare((PetscObject)viewer,PETSCVIEWERASCII,&iascii);
    115:   if (isdraw) {
    116:     MatFDColoringView_Draw(c,viewer);
    117:   } else if (iascii) {
    118:     PetscObjectPrintClassNamePrefixType((PetscObject)c,viewer);
    119:     PetscViewerASCIIPrintf(viewer,"  Error tolerance=%g\n",(double)c->error_rel);
    120:     PetscViewerASCIIPrintf(viewer,"  Umin=%g\n",(double)c->umin);
    121:     PetscViewerASCIIPrintf(viewer,"  Number of colors=%D\n",c->ncolors);

    123:     PetscViewerGetFormat(viewer,&format);
    124:     if (format != PETSC_VIEWER_ASCII_INFO) {
    125:       PetscInt row,col,nz;
    126:       nz = 0;
    127:       for (i=0; i<c->ncolors; i++) {
    128:         PetscViewerASCIIPrintf(viewer,"  Information for color %D\n",i);
    129:         PetscViewerASCIIPrintf(viewer,"    Number of columns %D\n",c->ncolumns[i]);
    130:         for (j=0; j<c->ncolumns[i]; j++) {
    131:           PetscViewerASCIIPrintf(viewer,"      %D\n",c->columns[i][j]);
    132:         }
    133:         PetscViewerASCIIPrintf(viewer,"    Number of rows %D\n",c->nrows[i]);
    134:         if (c->matentry) {
    135:           for (j=0; j<c->nrows[i]; j++) {
    136:             row  = c->matentry[nz].row;
    137:             col  = c->matentry[nz++].col;
    138:             PetscViewerASCIIPrintf(viewer,"      %D %D \n",row,col);
    139:           }
    140:         }
    141:       }
    142:     }
    143:     PetscViewerFlush(viewer);
    144:   }
    145:   return(0);
    146: }

    148: /*@
    149:    MatFDColoringSetParameters - Sets the parameters for the sparse approximation of
    150:    a Jacobian matrix using finite differences.

    152:    Logically Collective on MatFDColoring

    154:    The Jacobian is estimated with the differencing approximation
    155: .vb
    156:        F'(u)_{:,i} = [F(u+h*dx_{i}) - F(u)]/h where
    157:        htype = 'ds':
    158:          h = error_rel*u[i]                 if  abs(u[i]) > umin
    159:            = +/- error_rel*umin             otherwise, with +/- determined by the sign of u[i]
    160:          dx_{i} = (0, ... 1, .... 0)

    162:        htype = 'wp':
    163:          h = error_rel * sqrt(1 + ||u||)
    164: .ve

    166:    Input Parameters:
    167: +  coloring - the coloring context
    168: .  error_rel - relative error
    169: -  umin - minimum allowable u-value magnitude

    171:    Level: advanced

    173: .keywords: Mat, finite differences, coloring, set, parameters

    175: .seealso: MatFDColoringCreate(), MatFDColoringSetFromOptions()

    177: @*/
    178: PetscErrorCode MatFDColoringSetParameters(MatFDColoring matfd,PetscReal error,PetscReal umin)
    179: {
    184:   if (error != PETSC_DEFAULT) matfd->error_rel = error;
    185:   if (umin != PETSC_DEFAULT)  matfd->umin      = umin;
    186:   return(0);
    187: }

    189: /*@
    190:    MatFDColoringSetBlockSize - Sets block size for efficient inserting entries of Jacobian matrix.

    192:    Logically Collective on MatFDColoring

    194:    Input Parameters:
    195: +  coloring - the coloring context
    196: .  brows - number of rows in the block
    197: -  bcols - number of columns in the block

    199:    Level: intermediate

    201: .keywords: Mat, coloring

    203: .seealso: MatFDColoringCreate(), MatFDColoringSetFromOptions()

    205: @*/
    206: PetscErrorCode MatFDColoringSetBlockSize(MatFDColoring matfd,PetscInt brows,PetscInt bcols)
    207: {
    212:   if (brows != PETSC_DEFAULT) matfd->brows = brows;
    213:   if (bcols != PETSC_DEFAULT) matfd->bcols = bcols;
    214:   return(0);
    215: }

    217: /*@
    218:    MatFDColoringSetUp - Sets up the internal data structures of matrix coloring context for the later use.

    220:    Collective on Mat

    222:    Input Parameters:
    223: +  mat - the matrix containing the nonzero structure of the Jacobian
    224: .  iscoloring - the coloring of the matrix; usually obtained with MatGetColoring() or DMCreateColoring()
    225: -  color - the matrix coloring context

    227:    Level: beginner

    229: .keywords: MatFDColoring, setup

    231: .seealso: MatFDColoringCreate(), MatFDColoringDestroy()
    232: @*/
    233: PetscErrorCode MatFDColoringSetUp(Mat mat,ISColoring iscoloring,MatFDColoring color)
    234: {

    240:   if (color->setupcalled) return(0);

    242:   PetscLogEventBegin(MAT_FDColoringSetUp,mat,0,0,0);
    243:   if (mat->ops->fdcoloringsetup) {
    244:     (*mat->ops->fdcoloringsetup)(mat,iscoloring,color);
    245:   } else SETERRQ1(PetscObjectComm((PetscObject)mat),PETSC_ERR_SUP,"Code not yet written for matrix type %s",((PetscObject)mat)->type_name);

    247:   color->setupcalled = PETSC_TRUE;
    248:    PetscLogEventEnd(MAT_FDColoringSetUp,mat,0,0,0);
    249:   return(0);
    250: }

    252: /*@C
    253:    MatFDColoringGetFunction - Gets the function to use for computing the Jacobian.

    255:    Not Collective

    257:    Input Parameters:
    258: .  coloring - the coloring context

    260:    Output Parameters:
    261: +  f - the function
    262: -  fctx - the optional user-defined function context

    264:    Level: intermediate

    266: .keywords: Mat, Jacobian, finite differences, set, function

    268: .seealso: MatFDColoringCreate(), MatFDColoringSetFunction(), MatFDColoringSetFromOptions()

    270: @*/
    271: PetscErrorCode  MatFDColoringGetFunction(MatFDColoring matfd,PetscErrorCode (**f)(void),void **fctx)
    272: {
    275:   if (f) *f = matfd->f;
    276:   if (fctx) *fctx = matfd->fctx;
    277:   return(0);
    278: }

    280: /*@C
    281:    MatFDColoringSetFunction - Sets the function to use for computing the Jacobian.

    283:    Logically Collective on MatFDColoring

    285:    Input Parameters:
    286: +  coloring - the coloring context
    287: .  f - the function
    288: -  fctx - the optional user-defined function context

    290:    Calling sequence of (*f) function:
    291:     For SNES:    PetscErrorCode (*f)(SNES,Vec,Vec,void*)
    292:     If not using SNES: PetscErrorCode (*f)(void *dummy,Vec,Vec,void*) and dummy is ignored

    294:    Level: advanced

    296:    Notes:
    297:     This function is usually used automatically by SNES (when one uses SNESSetJacobian() with the argument
    298:      SNESComputeJacobianDefaultColor()) and only needs to be used by someone computing a matrix via coloring directly by
    299:      calling MatFDColoringApply()

    301:    Fortran Notes:
    302:     In Fortran you must call MatFDColoringSetFunction() for a coloring object to
    303:   be used without SNES or within the SNES solvers.

    305: .keywords: Mat, Jacobian, finite differences, set, function

    307: .seealso: MatFDColoringCreate(), MatFDColoringGetFunction(), MatFDColoringSetFromOptions()

    309: @*/
    310: PetscErrorCode  MatFDColoringSetFunction(MatFDColoring matfd,PetscErrorCode (*f)(void),void *fctx)
    311: {
    314:   matfd->f    = f;
    315:   matfd->fctx = fctx;
    316:   return(0);
    317: }

    319: /*@
    320:    MatFDColoringSetFromOptions - Sets coloring finite difference parameters from
    321:    the options database.

    323:    Collective on MatFDColoring

    325:    The Jacobian, F'(u), is estimated with the differencing approximation
    326: .vb
    327:        F'(u)_{:,i} = [F(u+h*dx_{i}) - F(u)]/h where
    328:        h = error_rel*u[i]                 if  abs(u[i]) > umin
    329:          = +/- error_rel*umin             otherwise, with +/- determined by the sign of u[i]
    330:        dx_{i} = (0, ... 1, .... 0)
    331: .ve

    333:    Input Parameter:
    334: .  coloring - the coloring context

    336:    Options Database Keys:
    337: +  -mat_fd_coloring_err <err> - Sets <err> (square root of relative error in the function)
    338: .  -mat_fd_coloring_umin <umin> - Sets umin, the minimum allowable u-value magnitude
    339: .  -mat_fd_type - "wp" or "ds" (see MATMFFD_WP or MATMFFD_DS)
    340: .  -mat_fd_coloring_view - Activates basic viewing
    341: .  -mat_fd_coloring_view ::ascii_info - Activates viewing info
    342: -  -mat_fd_coloring_view draw - Activates drawing

    344:     Level: intermediate

    346: .keywords: Mat, finite differences, parameters

    348: .seealso: MatFDColoringCreate(), MatFDColoringView(), MatFDColoringSetParameters()

    350: @*/
    351: PetscErrorCode  MatFDColoringSetFromOptions(MatFDColoring matfd)
    352: {
    354:   PetscBool      flg;
    355:   char           value[3];

    360:   PetscObjectOptionsBegin((PetscObject)matfd);
    361:   PetscOptionsReal("-mat_fd_coloring_err","Square root of relative error in function","MatFDColoringSetParameters",matfd->error_rel,&matfd->error_rel,0);
    362:   PetscOptionsReal("-mat_fd_coloring_umin","Minimum allowable u magnitude","MatFDColoringSetParameters",matfd->umin,&matfd->umin,0);
    363:   PetscOptionsString("-mat_fd_type","Algorithm to compute h, wp or ds","MatFDColoringCreate",matfd->htype,value,3,&flg);
    364:   if (flg) {
    365:     if (value[0] == 'w' && value[1] == 'p') matfd->htype = "wp";
    366:     else if (value[0] == 'd' && value[1] == 's') matfd->htype = "ds";
    367:     else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Unknown finite differencing type %s",value);
    368:   }
    369:   PetscOptionsInt("-mat_fd_coloring_brows","Number of block rows","MatFDColoringSetBlockSize",matfd->brows,&matfd->brows,NULL);
    370:   PetscOptionsInt("-mat_fd_coloring_bcols","Number of block columns","MatFDColoringSetBlockSize",matfd->bcols,&matfd->bcols,&flg);
    371:   if (flg && matfd->bcols > matfd->ncolors) {
    372:     /* input bcols cannot be > matfd->ncolors, thus set it as ncolors */
    373:     matfd->bcols = matfd->ncolors;
    374:   }

    376:   /* process any options handlers added with PetscObjectAddOptionsHandler() */
    377:   PetscObjectProcessOptionsHandlers(PetscOptionsObject,(PetscObject)matfd);
    378:   PetscOptionsEnd();
    379:   return(0);
    380: }

    382: /*@C
    383:    MatFDColoringSetType - Sets the approach for computing the finite difference parameter

    385:    Collective on MatFDColoring

    387:    Input Parameters:
    388: +  coloring - the coloring context
    389: -  type - either MATMFFD_WP or MATMFFD_DS

    391:    Options Database Keys:
    392: .  -mat_fd_type - "wp" or "ds"

    394:    Note: It is goofy that the argument type is MatMFFDType since the MatFDColoring actually computes the matrix entries
    395:          but the process of computing the entries is the same as as with the MatMFFD operation so we should reuse the names instead of
    396:          introducing another one.

    398:    Level: intermediate

    400: .keywords: Mat, finite differences, parameters

    402: .seealso: MatFDColoringCreate(), MatFDColoringView(), MatFDColoringSetParameters()

    404: @*/
    405: PetscErrorCode  MatFDColoringSetType(MatFDColoring matfd,MatMFFDType type)
    406: {
    409:   /*
    410:      It is goofy to handle the strings this way but currently there is no code to free a dynamically created matfd->htype
    411:      and this function is being provided as patch for a release so it shouldn't change the implementaton
    412:   */
    413:   if (type[0] == 'w' && type[1] == 'p') matfd->htype = "wp";
    414:   else if (type[0] == 'd' && type[1] == 's') matfd->htype = "ds";
    415:   else SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_ARG_OUTOFRANGE,"Unknown finite differencing type %s",type);
    416:   return(0);
    417: }

    419: PetscErrorCode MatFDColoringViewFromOptions(MatFDColoring fd,const char prefix[],const char optionname[])
    420: {
    421:   PetscErrorCode    ierr;
    422:   PetscBool         flg;
    423:   PetscViewer       viewer;
    424:   PetscViewerFormat format;

    427:   if (prefix) {
    428:     PetscOptionsGetViewer(PetscObjectComm((PetscObject)fd),prefix,optionname,&viewer,&format,&flg);
    429:   } else {
    430:     PetscOptionsGetViewer(PetscObjectComm((PetscObject)fd),((PetscObject)fd)->prefix,optionname,&viewer,&format,&flg);
    431:   }
    432:   if (flg) {
    433:     PetscViewerPushFormat(viewer,format);
    434:     MatFDColoringView(fd,viewer);
    435:     PetscViewerPopFormat(viewer);
    436:     PetscViewerDestroy(&viewer);
    437:   }
    438:   return(0);
    439: }

    441: /*@
    442:    MatFDColoringCreate - Creates a matrix coloring context for finite difference
    443:    computation of Jacobians.

    445:    Collective on Mat

    447:    Input Parameters:
    448: +  mat - the matrix containing the nonzero structure of the Jacobian
    449: -  iscoloring - the coloring of the matrix; usually obtained with MatColoringCreate() or DMCreateColoring()

    451:     Output Parameter:
    452: .   color - the new coloring context

    454:     Level: intermediate

    456: .seealso: MatFDColoringDestroy(),SNESComputeJacobianDefaultColor(), ISColoringCreate(),
    457:           MatFDColoringSetFunction(), MatFDColoringSetFromOptions(), MatFDColoringApply(),
    458:           MatFDColoringView(), MatFDColoringSetParameters(), MatColoringCreate(), DMCreateColoring()
    459: @*/
    460: PetscErrorCode  MatFDColoringCreate(Mat mat,ISColoring iscoloring,MatFDColoring *color)
    461: {
    462:   MatFDColoring  c;
    463:   MPI_Comm       comm;
    465:   PetscInt       M,N;

    469:   if (!mat->assembled) SETERRQ(PetscObjectComm((PetscObject)mat),PETSC_ERR_ARG_WRONGSTATE,"Matrix must be assembled by calls to MatAssemblyBegin/End();");
    470:   PetscLogEventBegin(MAT_FDColoringCreate,mat,0,0,0);
    471:   MatGetSize(mat,&M,&N);
    472:   if (M != N) SETERRQ(PetscObjectComm((PetscObject)mat),PETSC_ERR_SUP,"Only for square matrices");
    473:   PetscObjectGetComm((PetscObject)mat,&comm);
    474:   PetscHeaderCreate(c,MAT_FDCOLORING_CLASSID,"MatFDColoring","Jacobian computation via finite differences with coloring","Mat",comm,MatFDColoringDestroy,MatFDColoringView);

    476:   c->ctype = iscoloring->ctype;

    478:   if (mat->ops->fdcoloringcreate) {
    479:     (*mat->ops->fdcoloringcreate)(mat,iscoloring,c);
    480:   } else SETERRQ1(PetscObjectComm((PetscObject)mat),PETSC_ERR_SUP,"Code not yet written for matrix type %s",((PetscObject)mat)->type_name);

    482:   MatCreateVecs(mat,NULL,&c->w1);
    483:   PetscLogObjectParent((PetscObject)c,(PetscObject)c->w1);
    484:   VecDuplicate(c->w1,&c->w2);
    485:   PetscLogObjectParent((PetscObject)c,(PetscObject)c->w2);

    487:   c->error_rel    = PETSC_SQRT_MACHINE_EPSILON;
    488:   c->umin         = 100.0*PETSC_SQRT_MACHINE_EPSILON;
    489:   c->currentcolor = -1;
    490:   c->htype        = "wp";
    491:   c->fset         = PETSC_FALSE;
    492:   c->setupcalled  = PETSC_FALSE;

    494:   *color = c;
    495:   PetscObjectCompose((PetscObject)mat,"SNESMatFDColoring",(PetscObject)c);
    496:   PetscLogEventEnd(MAT_FDColoringCreate,mat,0,0,0);
    497:   return(0);
    498: }

    500: /*@
    501:     MatFDColoringDestroy - Destroys a matrix coloring context that was created
    502:     via MatFDColoringCreate().

    504:     Collective on MatFDColoring

    506:     Input Parameter:
    507: .   c - coloring context

    509:     Level: intermediate

    511: .seealso: MatFDColoringCreate()
    512: @*/
    513: PetscErrorCode  MatFDColoringDestroy(MatFDColoring *c)
    514: {
    516:   PetscInt       i;
    517:   MatFDColoring  color = *c;

    520:   if (!*c) return(0);
    521:   if (--((PetscObject)color)->refct > 0) {*c = 0; return(0);}

    523:   for (i=0; i<color->ncolors; i++) {
    524:     PetscFree(color->columns[i]);
    525:   }
    526:   PetscFree(color->ncolumns);
    527:   PetscFree(color->columns);
    528:   PetscFree(color->nrows);
    529:   if (color->htype[0] == 'w') {
    530:     PetscFree(color->matentry2);
    531:   } else {
    532:     PetscFree(color->matentry);
    533:   }
    534:   PetscFree(color->dy);
    535:   if (color->vscale) {VecDestroy(&color->vscale);}
    536:   VecDestroy(&color->w1);
    537:   VecDestroy(&color->w2);
    538:   VecDestroy(&color->w3);
    539:   PetscHeaderDestroy(c);
    540:   return(0);
    541: }

    543: /*@C
    544:     MatFDColoringGetPerturbedColumns - Returns the indices of the columns that
    545:       that are currently being perturbed.

    547:     Not Collective

    549:     Input Parameters:
    550: .   coloring - coloring context created with MatFDColoringCreate()

    552:     Output Parameters:
    553: +   n - the number of local columns being perturbed
    554: -   cols - the column indices, in global numbering

    556:    Level: advanced

    558:    Fortran Note:
    559:    This routine has a different interface for Fortran
    560: $     #include <petsc/finclude/petscmat.h>
    561: $          use petscmat
    562: $          PetscInt, pointer :: array(:)
    563: $          PetscErrorCode  ierr
    564: $          MatFDColoring   i
    565: $          call MatFDColoringGetPerturbedColumnsF90(i,array,ierr)
    566: $      use the entries of array ...
    567: $          call MatFDColoringRestorePerturbedColumnsF90(i,array,ierr)

    569: .seealso: MatFDColoringCreate(), MatFDColoringDestroy(), MatFDColoringView(), MatFDColoringApply()

    571: .keywords: coloring, Jacobian, finite differences
    572: @*/
    573: PetscErrorCode  MatFDColoringGetPerturbedColumns(MatFDColoring coloring,PetscInt *n,const PetscInt *cols[])
    574: {
    576:   if (coloring->currentcolor >= 0) {
    577:     *n    = coloring->ncolumns[coloring->currentcolor];
    578:     *cols = coloring->columns[coloring->currentcolor];
    579:   } else {
    580:     *n = 0;
    581:   }
    582:   return(0);
    583: }

    585: /*@
    586:     MatFDColoringApply - Given a matrix for which a MatFDColoring context
    587:     has been created, computes the Jacobian for a function via finite differences.

    589:     Collective on MatFDColoring

    591:     Input Parameters:
    592: +   mat - location to store Jacobian
    593: .   coloring - coloring context created with MatFDColoringCreate()
    594: .   x1 - location at which Jacobian is to be computed
    595: -   sctx - context required by function, if this is being used with the SNES solver then it is SNES object, otherwise it is null

    597:     Options Database Keys:
    598: +    -mat_fd_type - "wp" or "ds"  (see MATMFFD_WP or MATMFFD_DS)
    599: .    -mat_fd_coloring_view - Activates basic viewing or coloring
    600: .    -mat_fd_coloring_view draw - Activates drawing of coloring
    601: -    -mat_fd_coloring_view ::ascii_info - Activates viewing of coloring info

    603:     Level: intermediate

    605: .seealso: MatFDColoringCreate(), MatFDColoringDestroy(), MatFDColoringView(), MatFDColoringSetFunction()

    607: .keywords: coloring, Jacobian, finite differences
    608: @*/
    609: PetscErrorCode  MatFDColoringApply(Mat J,MatFDColoring coloring,Vec x1,void *sctx)
    610: {
    612:   PetscBool      flg = PETSC_FALSE;

    618:   if (!coloring->f) SETERRQ(PetscObjectComm((PetscObject)J),PETSC_ERR_ARG_WRONGSTATE,"Must call MatFDColoringSetFunction()");
    619:   if (!J->ops->fdcoloringapply) SETERRQ1(PETSC_COMM_SELF,PETSC_ERR_SUP,"Not supported for this matrix type %s",((PetscObject)J)->type_name);
    620:   if (!coloring->setupcalled) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_WRONGSTATE,"Must call MatFDColoringSetUp()");

    622:   MatSetUnfactored(J);
    623:   PetscOptionsGetBool(((PetscObject)coloring)->options,NULL,"-mat_fd_coloring_dont_rezero",&flg,NULL);
    624:   if (flg) {
    625:     PetscInfo(coloring,"Not calling MatZeroEntries()\n");
    626:   } else {
    627:     PetscBool assembled;
    628:     MatAssembled(J,&assembled);
    629:     if (assembled) {
    630:       MatZeroEntries(J);
    631:     }
    632:   }

    634:   PetscLogEventBegin(MAT_FDColoringApply,coloring,J,x1,0);
    635:   (*J->ops->fdcoloringapply)(J,coloring,x1,sctx);
    636:   PetscLogEventEnd(MAT_FDColoringApply,coloring,J,x1,0);
    637:   if (!coloring->viewed) {
    638:     MatFDColoringViewFromOptions(coloring,NULL,"-mat_fd_coloring_view");
    639:     coloring->viewed = PETSC_TRUE;
    640:   }
    641:   return(0);
    642: }