Actual source code: fdmatrix.c
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: {
12: PetscFunctionBegin;
13: if (F) {
14: PetscCall(VecCopy(F, fd->w1));
15: fd->fset = PETSC_TRUE;
16: } else {
17: fd->fset = PETSC_FALSE;
18: }
19: PetscFunctionReturn(PETSC_SUCCESS);
20: }
22: #include <petscdraw.h>
23: static PetscErrorCode MatFDColoringView_Draw_Zoom(PetscDraw draw, void *Aa)
24: {
25: MatFDColoring fd = (MatFDColoring)Aa;
26: PetscInt i, j, nz, row;
27: PetscReal x, y;
28: MatEntry *Jentry = fd->matentry;
30: PetscFunctionBegin;
31: /* loop over colors */
32: nz = 0;
33: for (i = 0; i < fd->ncolors; i++) {
34: for (j = 0; j < fd->nrows[i]; j++) {
35: row = Jentry[nz].row;
36: y = fd->M - row - fd->rstart;
37: x = (PetscReal)Jentry[nz++].col;
38: PetscCall(PetscDrawRectangle(draw, x, y, x + 1, y + 1, i + 1, i + 1, i + 1, i + 1));
39: }
40: }
41: PetscFunctionReturn(PETSC_SUCCESS);
42: }
44: static PetscErrorCode MatFDColoringView_Draw(MatFDColoring fd, PetscViewer viewer)
45: {
46: PetscBool isnull;
47: PetscDraw draw;
48: PetscReal xr, yr, xl, yl, h, w;
50: PetscFunctionBegin;
51: PetscCall(PetscViewerDrawGetDraw(viewer, 0, &draw));
52: PetscCall(PetscDrawIsNull(draw, &isnull));
53: if (isnull) PetscFunctionReturn(PETSC_SUCCESS);
55: xr = fd->N;
56: yr = fd->M;
57: h = yr / 10.0;
58: w = xr / 10.0;
59: xr += w;
60: yr += h;
61: xl = -w;
62: yl = -h;
63: PetscCall(PetscDrawSetCoordinates(draw, xl, yl, xr, yr));
64: PetscCall(PetscObjectCompose((PetscObject)fd, "Zoomviewer", (PetscObject)viewer));
65: PetscCall(PetscDrawZoom(draw, MatFDColoringView_Draw_Zoom, fd));
66: PetscCall(PetscObjectCompose((PetscObject)fd, "Zoomviewer", NULL));
67: PetscCall(PetscDrawSave(draw));
68: PetscFunctionReturn(PETSC_SUCCESS);
69: }
71: /*@C
72: MatFDColoringView - Views a finite difference coloring context.
74: Collective
76: Input Parameters:
77: + c - the coloring context
78: - viewer - visualization context
80: Level: intermediate
82: Notes:
83: The available visualization contexts include
84: + `PETSC_VIEWER_STDOUT_SELF` - standard output (default)
85: . `PETSC_VIEWER_STDOUT_WORLD` - synchronized standard
86: output where only the first processor opens
87: the file. All other processors send their
88: data to the first processor to print.
89: - `PETSC_VIEWER_DRAW_WORLD` - graphical display of nonzero structure
91: Since PETSc uses only a small number of basic colors (currently 33), if the coloring
92: involves more than 33 then some seemingly identical colors are displayed making it look
93: like an illegal coloring. This is just a graphical artifact.
95: .seealso: `Mat`, `MatFDColoring`, `MatFDColoringCreate()`
96: @*/
97: PetscErrorCode MatFDColoringView(MatFDColoring c, PetscViewer viewer)
98: {
99: PetscInt i, j;
100: PetscBool isdraw, iascii;
101: PetscViewerFormat format;
103: PetscFunctionBegin;
105: if (!viewer) PetscCall(PetscViewerASCIIGetStdout(PetscObjectComm((PetscObject)c), &viewer));
107: PetscCheckSameComm(c, 1, viewer, 2);
109: PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERDRAW, &isdraw));
110: PetscCall(PetscObjectTypeCompare((PetscObject)viewer, PETSCVIEWERASCII, &iascii));
111: if (isdraw) {
112: PetscCall(MatFDColoringView_Draw(c, viewer));
113: } else if (iascii) {
114: PetscCall(PetscObjectPrintClassNamePrefixType((PetscObject)c, viewer));
115: PetscCall(PetscViewerASCIIPrintf(viewer, " Error tolerance=%g\n", (double)c->error_rel));
116: PetscCall(PetscViewerASCIIPrintf(viewer, " Umin=%g\n", (double)c->umin));
117: PetscCall(PetscViewerASCIIPrintf(viewer, " Number of colors=%" PetscInt_FMT "\n", c->ncolors));
119: PetscCall(PetscViewerGetFormat(viewer, &format));
120: if (format != PETSC_VIEWER_ASCII_INFO) {
121: PetscInt row, col, nz;
122: nz = 0;
123: for (i = 0; i < c->ncolors; i++) {
124: PetscCall(PetscViewerASCIIPrintf(viewer, " Information for color %" PetscInt_FMT "\n", i));
125: PetscCall(PetscViewerASCIIPrintf(viewer, " Number of columns %" PetscInt_FMT "\n", c->ncolumns[i]));
126: for (j = 0; j < c->ncolumns[i]; j++) PetscCall(PetscViewerASCIIPrintf(viewer, " %" PetscInt_FMT "\n", c->columns[i][j]));
127: PetscCall(PetscViewerASCIIPrintf(viewer, " Number of rows %" PetscInt_FMT "\n", c->nrows[i]));
128: if (c->matentry) {
129: for (j = 0; j < c->nrows[i]; j++) {
130: row = c->matentry[nz].row;
131: col = c->matentry[nz++].col;
132: PetscCall(PetscViewerASCIIPrintf(viewer, " %" PetscInt_FMT " %" PetscInt_FMT " \n", row, col));
133: }
134: }
135: }
136: }
137: PetscCall(PetscViewerFlush(viewer));
138: }
139: PetscFunctionReturn(PETSC_SUCCESS);
140: }
142: /*@
143: MatFDColoringSetParameters - Sets the parameters for the sparse approximation of
144: a Jacobian matrix using finite differences.
146: Logically Collective
148: The Jacobian is estimated with the differencing approximation
149: .vb
150: F'(u)_{:,i} = [F(u+h*dx_{i}) - F(u)]/h where
151: htype = 'ds':
152: h = error_rel*u[i] if abs(u[i]) > umin
153: = +/- error_rel*umin otherwise, with +/- determined by the sign of u[i]
154: dx_{i} = (0, ... 1, .... 0)
156: htype = 'wp':
157: h = error_rel * sqrt(1 + ||u||)
158: .ve
160: Input Parameters:
161: + matfd - the coloring context
162: . error - relative error
163: - umin - minimum allowable u-value magnitude
165: Level: advanced
167: .seealso: `Mat`, `MatFDColoring`, `MatFDColoringCreate()`, `MatFDColoringSetFromOptions()`
168: @*/
169: PetscErrorCode MatFDColoringSetParameters(MatFDColoring matfd, PetscReal error, PetscReal umin)
170: {
171: PetscFunctionBegin;
175: if (error != PETSC_DEFAULT) matfd->error_rel = error;
176: if (umin != PETSC_DEFAULT) matfd->umin = umin;
177: PetscFunctionReturn(PETSC_SUCCESS);
178: }
180: /*@
181: MatFDColoringSetBlockSize - Sets block size for efficient inserting entries of Jacobian matrix.
183: Logically Collective
185: Input Parameters:
186: + coloring - the coloring context
187: . brows - number of rows in the block
188: - bcols - number of columns in the block
190: Level: intermediate
192: .seealso: `Mat`, `MatFDColoring`, `MatFDColoringCreate()`, `MatFDColoringSetFromOptions()`
193: @*/
194: PetscErrorCode MatFDColoringSetBlockSize(MatFDColoring matfd, PetscInt brows, PetscInt bcols)
195: {
196: PetscFunctionBegin;
200: if (brows != PETSC_DEFAULT) matfd->brows = brows;
201: if (bcols != PETSC_DEFAULT) matfd->bcols = bcols;
202: PetscFunctionReturn(PETSC_SUCCESS);
203: }
205: /*@
206: MatFDColoringSetUp - Sets up the internal data structures of matrix coloring context for the later use.
208: Collective
210: Input Parameters:
211: + mat - the matrix containing the nonzero structure of the Jacobian
212: . iscoloring - the coloring of the matrix; usually obtained with `MatGetColoring()` or `DMCreateColoring()`
213: - color - the matrix coloring context
215: Level: beginner
217: Notes:
218: When the coloring type is `IS_COLORING_LOCAL` the coloring is in the local ordering of the unknowns.
220: .seealso: `Mat`, `MatFDColoring`, `MatFDColoringCreate()`, `MatFDColoringDestroy()`
221: @*/
222: PetscErrorCode MatFDColoringSetUp(Mat mat, ISColoring iscoloring, MatFDColoring color)
223: {
224: PetscBool eq;
226: PetscFunctionBegin;
229: if (color->setupcalled) PetscFunctionReturn(PETSC_SUCCESS);
230: PetscCall(PetscObjectCompareId((PetscObject)mat, color->matid, &eq));
231: PetscCheck(eq, PetscObjectComm((PetscObject)mat), PETSC_ERR_ARG_WRONG, "Matrix used with MatFDColoringSetUp() must be that used with MatFDColoringCreate()");
233: PetscCall(PetscLogEventBegin(MAT_FDColoringSetUp, mat, 0, 0, 0));
234: PetscUseTypeMethod(mat, fdcoloringsetup, iscoloring, color);
236: color->setupcalled = PETSC_TRUE;
237: PetscCall(PetscLogEventEnd(MAT_FDColoringSetUp, mat, 0, 0, 0));
238: PetscFunctionReturn(PETSC_SUCCESS);
239: }
241: /*@C
242: MatFDColoringGetFunction - Gets the function to use for computing the Jacobian.
244: Not Collective
246: Input Parameter:
247: . coloring - the coloring context
249: Output Parameters:
250: + f - the function
251: - fctx - the optional user-defined function context
253: Level: intermediate
255: .seealso: `Mat`, `MatFDColoring`, `MatFDColoringCreate()`, `MatFDColoringSetFunction()`, `MatFDColoringSetFromOptions()`
256: @*/
257: PetscErrorCode MatFDColoringGetFunction(MatFDColoring matfd, PetscErrorCode (**f)(void), void **fctx)
258: {
259: PetscFunctionBegin;
261: if (f) *f = matfd->f;
262: if (fctx) *fctx = matfd->fctx;
263: PetscFunctionReturn(PETSC_SUCCESS);
264: }
266: /*@C
267: MatFDColoringSetFunction - Sets the function to use for computing the Jacobian.
269: Logically Collective
271: Input Parameters:
272: + coloring - the coloring context
273: . f - the function
274: - fctx - the optional user-defined function context
276: Calling sequence of (*f) function:
277: For `SNES` use PetscErrorCode (*f)(SNES,Vec,Vec,void*)
278: If not using `SNES` use PetscErrorCode (*f)(void *dummy,Vec,Vec,void*) and dummy is ignored
280: Level: advanced
282: Note:
283: This function is usually used automatically by `SNES` (when one uses `SNESSetJacobian()` with the argument
284: `SNESComputeJacobianDefaultColor()`) and only needs to be used by someone computing a matrix via coloring directly by
285: calling `MatFDColoringApply()`
287: Fortran Note:
288: In Fortran you must call `MatFDColoringSetFunction()` for a coloring object to
289: be used without `SNES` or within the `SNES` solvers.
291: .seealso: `Mat`, `MatFDColoring`, `MatFDColoringCreate()`, `MatFDColoringGetFunction()`, `MatFDColoringSetFromOptions()`
292: @*/
293: PetscErrorCode MatFDColoringSetFunction(MatFDColoring matfd, PetscErrorCode (*f)(void), void *fctx)
294: {
295: PetscFunctionBegin;
297: matfd->f = f;
298: matfd->fctx = fctx;
299: PetscFunctionReturn(PETSC_SUCCESS);
300: }
302: /*@
303: MatFDColoringSetFromOptions - Sets coloring finite difference parameters from
304: the options database.
306: Collective
308: The Jacobian, F'(u), is estimated with the differencing approximation
309: .vb
310: F'(u)_{:,i} = [F(u+h*dx_{i}) - F(u)]/h where
311: h = error_rel*u[i] if abs(u[i]) > umin
312: = +/- error_rel*umin otherwise, with +/- determined by the sign of u[i]
313: dx_{i} = (0, ... 1, .... 0)
314: .ve
316: Input Parameter:
317: . coloring - the coloring context
319: Options Database Keys:
320: + -mat_fd_coloring_err <err> - Sets <err> (square root of relative error in the function)
321: . -mat_fd_coloring_umin <umin> - Sets umin, the minimum allowable u-value magnitude
322: . -mat_fd_type - "wp" or "ds" (see MATMFFD_WP or MATMFFD_DS)
323: . -mat_fd_coloring_view - Activates basic viewing
324: . -mat_fd_coloring_view ::ascii_info - Activates viewing info
325: - -mat_fd_coloring_view draw - Activates drawing
327: Level: intermediate
329: .seealso: `Mat`, `MatFDColoring`, `MatFDColoringCreate()`, `MatFDColoringView()`, `MatFDColoringSetParameters()`
330: @*/
331: PetscErrorCode MatFDColoringSetFromOptions(MatFDColoring matfd)
332: {
333: PetscBool flg;
334: char value[3];
336: PetscFunctionBegin;
339: PetscObjectOptionsBegin((PetscObject)matfd);
340: PetscCall(PetscOptionsReal("-mat_fd_coloring_err", "Square root of relative error in function", "MatFDColoringSetParameters", matfd->error_rel, &matfd->error_rel, NULL));
341: PetscCall(PetscOptionsReal("-mat_fd_coloring_umin", "Minimum allowable u magnitude", "MatFDColoringSetParameters", matfd->umin, &matfd->umin, NULL));
342: PetscCall(PetscOptionsString("-mat_fd_type", "Algorithm to compute h, wp or ds", "MatFDColoringCreate", matfd->htype, value, sizeof(value), &flg));
343: if (flg) {
344: if (value[0] == 'w' && value[1] == 'p') matfd->htype = "wp";
345: else if (value[0] == 'd' && value[1] == 's') matfd->htype = "ds";
346: else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Unknown finite differencing type %s", value);
347: }
348: PetscCall(PetscOptionsInt("-mat_fd_coloring_brows", "Number of block rows", "MatFDColoringSetBlockSize", matfd->brows, &matfd->brows, NULL));
349: PetscCall(PetscOptionsInt("-mat_fd_coloring_bcols", "Number of block columns", "MatFDColoringSetBlockSize", matfd->bcols, &matfd->bcols, &flg));
350: if (flg && matfd->bcols > matfd->ncolors) {
351: /* input bcols cannot be > matfd->ncolors, thus set it as ncolors */
352: matfd->bcols = matfd->ncolors;
353: }
355: /* process any options handlers added with PetscObjectAddOptionsHandler() */
356: PetscCall(PetscObjectProcessOptionsHandlers((PetscObject)matfd, PetscOptionsObject));
357: PetscOptionsEnd();
358: PetscFunctionReturn(PETSC_SUCCESS);
359: }
361: /*@C
362: MatFDColoringSetType - Sets the approach for computing the finite difference parameter
364: Collective
366: Input Parameters:
367: + coloring - the coloring context
368: - type - either `MATMFFD_WP` or `MATMFFD_DS`
370: Options Database Keys:
371: . -mat_fd_type - "wp" or "ds"
373: Level: intermediate
375: Note:
376: It is goofy that the argument type is `MatMFFDType` since the `MatFDColoring` actually computes the matrix entries
377: but the process of computing the entries is the same as as with the `MATMFFD` operation so we should reuse the names instead of
378: introducing another one.
380: .seealso: `Mat`, `MatFDColoring`, `MatFDColoringCreate()`, `MatFDColoringView()`, `MatFDColoringSetParameters()`
381: @*/
382: PetscErrorCode MatFDColoringSetType(MatFDColoring matfd, MatMFFDType type)
383: {
384: PetscFunctionBegin;
386: /*
387: It is goofy to handle the strings this way but currently there is no code to free a dynamically created matfd->htype
388: and this function is being provided as patch for a release so it shouldn't change the implementation
389: */
390: if (type[0] == 'w' && type[1] == 'p') matfd->htype = "wp";
391: else if (type[0] == 'd' && type[1] == 's') matfd->htype = "ds";
392: else SETERRQ(PETSC_COMM_SELF, PETSC_ERR_ARG_OUTOFRANGE, "Unknown finite differencing type %s", type);
393: PetscFunctionReturn(PETSC_SUCCESS);
394: }
396: PetscErrorCode MatFDColoringViewFromOptions(MatFDColoring fd, const char prefix[], const char optionname[])
397: {
398: PetscBool flg;
399: PetscViewer viewer;
400: PetscViewerFormat format;
402: PetscFunctionBegin;
403: if (prefix) {
404: PetscCall(PetscOptionsGetViewer(PetscObjectComm((PetscObject)fd), ((PetscObject)fd)->options, prefix, optionname, &viewer, &format, &flg));
405: } else {
406: PetscCall(PetscOptionsGetViewer(PetscObjectComm((PetscObject)fd), ((PetscObject)fd)->options, ((PetscObject)fd)->prefix, optionname, &viewer, &format, &flg));
407: }
408: if (flg) {
409: PetscCall(PetscViewerPushFormat(viewer, format));
410: PetscCall(MatFDColoringView(fd, viewer));
411: PetscCall(PetscViewerPopFormat(viewer));
412: PetscCall(PetscViewerDestroy(&viewer));
413: }
414: PetscFunctionReturn(PETSC_SUCCESS);
415: }
417: /*@
418: MatFDColoringCreate - Creates a matrix coloring context for finite difference
419: computation of Jacobians.
421: Collective
423: Input Parameters:
424: + mat - the matrix containing the nonzero structure of the Jacobian
425: - iscoloring - the coloring of the matrix; usually obtained with `MatColoringCreate()` or `DMCreateColoring()`
427: Output Parameter:
428: . color - the new coloring context
430: Level: intermediate
432: .seealso: `Mat`, `MatFDColoring`, `MatFDColoringDestroy()`, `SNESComputeJacobianDefaultColor()`, `ISColoringCreate()`,
433: `MatFDColoringSetFunction()`, `MatFDColoringSetFromOptions()`, `MatFDColoringApply()`,
434: `MatFDColoringView()`, `MatFDColoringSetParameters()`, `MatColoringCreate()`, `DMCreateColoring()`, `MatFDColoringSetValues()`
435: @*/
436: PetscErrorCode MatFDColoringCreate(Mat mat, ISColoring iscoloring, MatFDColoring *color)
437: {
438: MatFDColoring c;
439: MPI_Comm comm;
440: PetscInt M, N;
442: PetscFunctionBegin;
444: PetscCheck(mat->assembled, PetscObjectComm((PetscObject)mat), PETSC_ERR_ARG_WRONGSTATE, "Matrix must be assembled by calls to MatAssemblyBegin/End();");
445: PetscCall(PetscLogEventBegin(MAT_FDColoringCreate, mat, 0, 0, 0));
446: PetscCall(MatGetSize(mat, &M, &N));
447: PetscCheck(M == N, PetscObjectComm((PetscObject)mat), PETSC_ERR_SUP, "Only for square matrices");
448: PetscCall(PetscObjectGetComm((PetscObject)mat, &comm));
449: PetscCall(PetscHeaderCreate(c, MAT_FDCOLORING_CLASSID, "MatFDColoring", "Jacobian computation via finite differences with coloring", "Mat", comm, MatFDColoringDestroy, MatFDColoringView));
451: c->ctype = iscoloring->ctype;
452: PetscCall(PetscObjectGetId((PetscObject)mat, &c->matid));
454: PetscUseTypeMethod(mat, fdcoloringcreate, iscoloring, c);
456: PetscCall(MatCreateVecs(mat, NULL, &c->w1));
457: /* Vec is used intensively in particular piece of scalar CPU code; won't benefit from bouncing back and forth to the GPU */
458: PetscCall(VecBindToCPU(c->w1, PETSC_TRUE));
459: PetscCall(VecDuplicate(c->w1, &c->w2));
460: /* Vec is used intensively in particular piece of scalar CPU code; won't benefit from bouncing back and forth to the GPU */
461: PetscCall(VecBindToCPU(c->w2, PETSC_TRUE));
463: c->error_rel = PETSC_SQRT_MACHINE_EPSILON;
464: c->umin = 100.0 * PETSC_SQRT_MACHINE_EPSILON;
465: c->currentcolor = -1;
466: c->htype = "wp";
467: c->fset = PETSC_FALSE;
468: c->setupcalled = PETSC_FALSE;
470: *color = c;
471: PetscCall(PetscObjectCompose((PetscObject)mat, "SNESMatFDColoring", (PetscObject)c));
472: PetscCall(PetscLogEventEnd(MAT_FDColoringCreate, mat, 0, 0, 0));
473: PetscFunctionReturn(PETSC_SUCCESS);
474: }
476: /*@
477: MatFDColoringDestroy - Destroys a matrix coloring context that was created
478: via `MatFDColoringCreate()`.
480: Collective
482: Input Parameter:
483: . c - coloring context
485: Level: intermediate
487: .seealso: `Mat`, `MatFDColoring`, `MatFDColoringCreate()`
488: @*/
489: PetscErrorCode MatFDColoringDestroy(MatFDColoring *c)
490: {
491: PetscInt i;
492: MatFDColoring color = *c;
494: PetscFunctionBegin;
495: if (!*c) PetscFunctionReturn(PETSC_SUCCESS);
496: if (--((PetscObject)color)->refct > 0) {
497: *c = NULL;
498: PetscFunctionReturn(PETSC_SUCCESS);
499: }
501: /* we do not free the column arrays since their entries are owned by the ISs in color->isa */
502: for (i = 0; i < color->ncolors; i++) PetscCall(ISDestroy(&color->isa[i]));
503: PetscCall(PetscFree(color->isa));
504: PetscCall(PetscFree2(color->ncolumns, color->columns));
505: PetscCall(PetscFree(color->nrows));
506: if (color->htype[0] == 'w') {
507: PetscCall(PetscFree(color->matentry2));
508: } else {
509: PetscCall(PetscFree(color->matentry));
510: }
511: PetscCall(PetscFree(color->dy));
512: if (color->vscale) PetscCall(VecDestroy(&color->vscale));
513: PetscCall(VecDestroy(&color->w1));
514: PetscCall(VecDestroy(&color->w2));
515: PetscCall(VecDestroy(&color->w3));
516: PetscCall(PetscHeaderDestroy(c));
517: PetscFunctionReturn(PETSC_SUCCESS);
518: }
520: /*@C
521: MatFDColoringGetPerturbedColumns - Returns the indices of the columns that
522: that are currently being perturbed.
524: Not Collective
526: Input Parameter:
527: . coloring - coloring context created with `MatFDColoringCreate()`
529: Output Parameters:
530: + n - the number of local columns being perturbed
531: - cols - the column indices, in global numbering
533: Level: advanced
535: Note:
536: IF the matrix type is `MATBAIJ`, then the block column indices are returned
538: Fortran Note:
539: This routine has a different interface for Fortran
540: .vb
541: #include <petsc/finclude/petscmat.h>
542: use petscmat
543: PetscInt, pointer :: array(:)
544: PetscErrorCode ierr
545: MatFDColoring i
546: call MatFDColoringGetPerturbedColumnsF90(i,array,ierr)
547: use the entries of array ...
548: call MatFDColoringRestorePerturbedColumnsF90(i,array,ierr)
549: .ve
551: .seealso: `Mat`, `MatFDColoring`, `MatFDColoringCreate()`, `MatFDColoringDestroy()`, `MatFDColoringView()`, `MatFDColoringApply()`
552: @*/
553: PetscErrorCode MatFDColoringGetPerturbedColumns(MatFDColoring coloring, PetscInt *n, const PetscInt *cols[])
554: {
555: PetscFunctionBegin;
556: if (coloring->currentcolor >= 0) {
557: *n = coloring->ncolumns[coloring->currentcolor];
558: *cols = coloring->columns[coloring->currentcolor];
559: } else {
560: *n = 0;
561: }
562: PetscFunctionReturn(PETSC_SUCCESS);
563: }
565: /*@
566: MatFDColoringApply - Given a matrix for which a `MatFDColoring` context
567: has been created, computes the Jacobian for a function via finite differences.
569: Collective
571: Input Parameters:
572: + mat - location to store Jacobian
573: . coloring - coloring context created with `MatFDColoringCreate()`
574: . x1 - location at which Jacobian is to be computed
575: - sctx - context required by function, if this is being used with the SNES solver then it is `SNES` object, otherwise it is null
577: Options Database Keys:
578: + -mat_fd_type - "wp" or "ds" (see `MATMFFD_WP` or `MATMFFD_DS`)
579: . -mat_fd_coloring_view - Activates basic viewing or coloring
580: . -mat_fd_coloring_view draw - Activates drawing of coloring
581: - -mat_fd_coloring_view ::ascii_info - Activates viewing of coloring info
583: Level: intermediate
585: .seealso: `Mat`, `MatFDColoring`, `MatFDColoringCreate()`, `MatFDColoringDestroy()`, `MatFDColoringView()`, `MatFDColoringSetFunction()`, `MatFDColoringSetValues()`
586: @*/
587: PetscErrorCode MatFDColoringApply(Mat J, MatFDColoring coloring, Vec x1, void *sctx)
588: {
589: PetscBool eq;
591: PetscFunctionBegin;
595: PetscCall(PetscObjectCompareId((PetscObject)J, coloring->matid, &eq));
596: PetscCheck(eq, PetscObjectComm((PetscObject)J), PETSC_ERR_ARG_WRONG, "Matrix used with MatFDColoringApply() must be that used with MatFDColoringCreate()");
597: PetscCheck(coloring->f, PetscObjectComm((PetscObject)J), PETSC_ERR_ARG_WRONGSTATE, "Must call MatFDColoringSetFunction()");
598: PetscCheck(coloring->setupcalled, PETSC_COMM_SELF, PETSC_ERR_ARG_WRONGSTATE, "Must call MatFDColoringSetUp()");
600: PetscCall(MatSetUnfactored(J));
601: PetscCall(PetscLogEventBegin(MAT_FDColoringApply, coloring, J, x1, 0));
602: PetscUseTypeMethod(J, fdcoloringapply, coloring, x1, sctx);
603: PetscCall(PetscLogEventEnd(MAT_FDColoringApply, coloring, J, x1, 0));
604: if (!coloring->viewed) {
605: PetscCall(MatFDColoringViewFromOptions(coloring, NULL, "-mat_fd_coloring_view"));
606: coloring->viewed = PETSC_TRUE;
607: }
608: PetscFunctionReturn(PETSC_SUCCESS);
609: }