xref: /petsc/src/sys/classes/viewer/impls/matlab/vmatlab.c (revision 2e956fe4fc852fabc23b437482e1fb7b77fddb0d)
15c6c1daeSBarry Smith 
2af0996ceSBarry Smith #include <petsc/private/viewerimpl.h>
35c6c1daeSBarry Smith #include <mat.h>
45c6c1daeSBarry Smith 
55c6c1daeSBarry Smith typedef struct {
65c6c1daeSBarry Smith   MATFile       *ep;
75c6c1daeSBarry Smith   PetscMPIInt   rank;
85c6c1daeSBarry Smith   PetscFileMode btype;
95c6c1daeSBarry Smith } PetscViewer_Matlab;
105c6c1daeSBarry Smith 
115c6c1daeSBarry Smith /*@C
125c6c1daeSBarry Smith     PetscViewerMatlabPutArray - Puts an array into the MATLAB viewer.
135c6c1daeSBarry Smith 
145c6c1daeSBarry Smith       Not collective: only processor zero saves the array
155c6c1daeSBarry Smith 
165c6c1daeSBarry Smith     Input Parameters:
175c6c1daeSBarry Smith +    mfile - the viewer
185c6c1daeSBarry Smith .    m,n - the dimensions of the array
195c6c1daeSBarry Smith .    array - the array (represented in one dimension)
205c6c1daeSBarry Smith -    name - the name of the array
215c6c1daeSBarry Smith 
225c6c1daeSBarry Smith    Level: advanced
235c6c1daeSBarry Smith 
2495452b02SPatrick Sanan      Notes:
2595452b02SPatrick Sanan     Only writes array values on processor 0.
265c6c1daeSBarry Smith 
275c6c1daeSBarry Smith @*/
285c6c1daeSBarry Smith PetscErrorCode  PetscViewerMatlabPutArray(PetscViewer mfile,int m,int n,const PetscScalar *array,const char *name)
295c6c1daeSBarry Smith {
302cb5e1ccSBarry Smith   PetscViewer_Matlab *ml;
315c6c1daeSBarry Smith   mxArray            *mat;
325c6c1daeSBarry Smith 
335c6c1daeSBarry Smith   PetscFunctionBegin;
3428b400f6SJacob Faibussowitsch   PetscCheck(mfile,PETSC_COMM_SELF,PETSC_ERR_ARG_NULL,"Null argument: probably PETSC_VIEWER_MATLAB_() failed");
352cb5e1ccSBarry Smith   ml = (PetscViewer_Matlab*)mfile->data;
365c6c1daeSBarry Smith   if (!ml->rank) {
379566063dSJacob Faibussowitsch     PetscCall(PetscInfo(mfile,"Putting MATLAB array %s\n",name));
385c6c1daeSBarry Smith #if !defined(PETSC_USE_COMPLEX)
395c6c1daeSBarry Smith     mat  = mxCreateDoubleMatrix(m,n,mxREAL);
405c6c1daeSBarry Smith #else
415c6c1daeSBarry Smith     mat  = mxCreateDoubleMatrix(m,n,mxCOMPLEX);
425c6c1daeSBarry Smith #endif
439566063dSJacob Faibussowitsch     PetscCall(PetscArraycpy(mxGetPr(mat),array,m*n));
445c6c1daeSBarry Smith     matPutVariable(ml->ep,name,mat);
455c6c1daeSBarry Smith 
469566063dSJacob Faibussowitsch     PetscCall(PetscInfo(mfile,"Put MATLAB array %s\n",name));
475c6c1daeSBarry Smith   }
485c6c1daeSBarry Smith   PetscFunctionReturn(0);
495c6c1daeSBarry Smith }
505c6c1daeSBarry Smith 
515c6c1daeSBarry Smith PetscErrorCode  PetscViewerMatlabPutVariable(PetscViewer viewer,const char *name,void *mat)
525c6c1daeSBarry Smith {
53a297a907SKarl Rupp   PetscViewer_Matlab *ml = (PetscViewer_Matlab*)viewer->data;
545c6c1daeSBarry Smith 
555c6c1daeSBarry Smith   PetscFunctionBegin;
565c6c1daeSBarry Smith   matPutVariable(ml->ep,name,(mxArray*)mat);
575c6c1daeSBarry Smith   PetscFunctionReturn(0);
585c6c1daeSBarry Smith }
595c6c1daeSBarry Smith 
605c6c1daeSBarry Smith /*@C
615c6c1daeSBarry Smith     PetscViewerMatlabGetArray - Gets a variable from a MATLAB viewer into an array
625c6c1daeSBarry Smith 
635c6c1daeSBarry Smith     Not Collective; only processor zero reads in the array
645c6c1daeSBarry Smith 
655c6c1daeSBarry Smith     Input Parameters:
665c6c1daeSBarry Smith +    mfile - the MATLAB file viewer
675c6c1daeSBarry Smith .    m,n - the dimensions of the array
685c6c1daeSBarry Smith .    array - the array (represented in one dimension)
695c6c1daeSBarry Smith -    name - the name of the array
705c6c1daeSBarry Smith 
715c6c1daeSBarry Smith    Level: advanced
725c6c1daeSBarry Smith 
7395452b02SPatrick Sanan      Notes:
7495452b02SPatrick Sanan     Only reads in array values on processor 0.
755c6c1daeSBarry Smith 
765c6c1daeSBarry Smith @*/
775c6c1daeSBarry Smith PetscErrorCode  PetscViewerMatlabGetArray(PetscViewer mfile,int m,int n,PetscScalar *array,const char *name)
785c6c1daeSBarry Smith {
792cb5e1ccSBarry Smith   PetscViewer_Matlab *ml;
805c6c1daeSBarry Smith   mxArray            *mat;
815c6c1daeSBarry Smith 
825c6c1daeSBarry Smith   PetscFunctionBegin;
8328b400f6SJacob Faibussowitsch   PetscCheck(mfile,PETSC_COMM_SELF,PETSC_ERR_ARG_NULL,"Null argument: probably PETSC_VIEWER_MATLAB_() failed");
842cb5e1ccSBarry Smith   ml = (PetscViewer_Matlab*)mfile->data;
855c6c1daeSBarry Smith   if (!ml->rank) {
869566063dSJacob Faibussowitsch     PetscCall(PetscInfo(mfile,"Getting MATLAB array %s\n",name));
875c6c1daeSBarry Smith     mat  = matGetVariable(ml->ep,name);
8828b400f6SJacob Faibussowitsch     PetscCheck(mat,PETSC_COMM_SELF,PETSC_ERR_LIB,"Unable to get array %s from matlab",name);
899566063dSJacob Faibussowitsch     PetscCall(PetscArraycpy(array,mxGetPr(mat),m*n));
909566063dSJacob Faibussowitsch     PetscCall(PetscInfo(mfile,"Got MATLAB array %s\n",name));
915c6c1daeSBarry Smith   }
925c6c1daeSBarry Smith   PetscFunctionReturn(0);
935c6c1daeSBarry Smith }
945c6c1daeSBarry Smith 
955c6c1daeSBarry Smith PetscErrorCode  PetscViewerFileSetMode_Matlab(PetscViewer viewer,PetscFileMode type)
965c6c1daeSBarry Smith {
975c6c1daeSBarry Smith   PetscViewer_Matlab *vmatlab = (PetscViewer_Matlab*)viewer->data;
985c6c1daeSBarry Smith 
995c6c1daeSBarry Smith   PetscFunctionBegin;
1005c6c1daeSBarry Smith   vmatlab->btype = type;
1015c6c1daeSBarry Smith   PetscFunctionReturn(0);
1025c6c1daeSBarry Smith }
1035c6c1daeSBarry Smith 
1045c6c1daeSBarry Smith /*
1055c6c1daeSBarry Smith         Actually opens the file
1065c6c1daeSBarry Smith */
1075c6c1daeSBarry Smith PetscErrorCode  PetscViewerFileSetName_Matlab(PetscViewer viewer,const char name[])
1085c6c1daeSBarry Smith {
1095c6c1daeSBarry Smith   PetscViewer_Matlab *vmatlab = (PetscViewer_Matlab*)viewer->data;
1105c6c1daeSBarry Smith   PetscFileMode      type     = vmatlab->btype;
1115c6c1daeSBarry Smith 
1125c6c1daeSBarry Smith   PetscFunctionBegin;
113cc73adaaSBarry Smith   PetscCheck(type != (PetscFileMode) -1,PETSC_COMM_SELF,PETSC_ERR_ORDER,"Must call PetscViewerFileSetMode() before PetscViewerFileSetName()");
1145c6c1daeSBarry Smith   if (vmatlab->ep) matClose(vmatlab->ep);
1155c6c1daeSBarry Smith 
1165c6c1daeSBarry Smith   /* only first processor opens file */
1175c6c1daeSBarry Smith   if (!vmatlab->rank) {
118a297a907SKarl Rupp     if (type == FILE_MODE_READ) vmatlab->ep = matOpen(name,"r");
1197e4fd573SVaclav Hapla     else if (type == FILE_MODE_WRITE) vmatlab->ep = matOpen(name,"w");
12008401ef6SPierre Jolivet     else PetscCheck(type != FILE_MODE_UNDEFINED,PetscObjectComm((PetscObject)viewer),PETSC_ERR_ORDER, "Must call PetscViewerFileSetMode() before PetscViewerFileSetName()");
12198921bdaSJacob Faibussowitsch     else SETERRQ(PetscObjectComm((PetscObject)viewer),PETSC_ERR_SUP, "Unsupported file mode %s",PetscFileModes[type]);
1225c6c1daeSBarry Smith   }
1235c6c1daeSBarry Smith   PetscFunctionReturn(0);
1245c6c1daeSBarry Smith }
1255c6c1daeSBarry Smith 
1265c6c1daeSBarry Smith PetscErrorCode PetscViewerDestroy_Matlab(PetscViewer v)
1275c6c1daeSBarry Smith {
1285c6c1daeSBarry Smith   PetscViewer_Matlab *vf = (PetscViewer_Matlab*)v->data;
1295c6c1daeSBarry Smith 
1305c6c1daeSBarry Smith   PetscFunctionBegin;
1315c6c1daeSBarry Smith   if (vf->ep) matClose(vf->ep);
1329566063dSJacob Faibussowitsch   PetscCall(PetscFree(vf));
133*2e956fe4SStefano Zampini   PetscCall(PetscObjectComposeFunction((PetscObject)v,"PetscViewerFileSetName_C",NULL));
134*2e956fe4SStefano Zampini   PetscCall(PetscObjectComposeFunction((PetscObject)v,"PetscViewerFileSetMode_C",NULL));
1355c6c1daeSBarry Smith   PetscFunctionReturn(0);
1365c6c1daeSBarry Smith }
1375c6c1daeSBarry Smith 
1388556b5ebSBarry Smith /*MC
1398556b5ebSBarry Smith    PETSCVIEWERMATLAB - A viewer that saves the variables into a MATLAB .mat file that may be read into MATLAB
1408556b5ebSBarry Smith        with load('filename').
1418556b5ebSBarry Smith 
1428556b5ebSBarry Smith    Level: intermediate
1438556b5ebSBarry Smith 
1448556b5ebSBarry Smith        Note: Currently can only save PETSc vectors to .mat files, not matrices (use the PETSCVIEWERBINARY and
1458556b5ebSBarry Smith              ${PETSC_DIR}/share/petsc/matlab/PetscBinaryRead.m to read matrices into MATLAB).
1468556b5ebSBarry Smith 
1478556b5ebSBarry Smith              For parallel vectors obtained with DMCreateGlobalVector() or DMGetGlobalVector() the vectors are saved to
1488556b5ebSBarry Smith              the .mat file in natural ordering. You can use DMView() to save the DMDA information to the .mat file
1498556b5ebSBarry Smith              the fields in the MATLAB loaded da variable give the array dimensions so you can reshape the MATLAB
1508556b5ebSBarry Smith              vector to the same multidimensional shape as it had in PETSc for plotting etc. For example,
1518556b5ebSBarry Smith 
1528556b5ebSBarry Smith $             In your PETSc C/C++ code (assuming a two dimensional DMDA with one degree of freedom per node)
1538556b5ebSBarry Smith $                PetscObjectSetName((PetscObject)x,"x");
1548556b5ebSBarry Smith $                VecView(x,PETSC_VIEWER_MATLAB_WORLD);
1558556b5ebSBarry Smith $                PetscObjectSetName((PetscObject)da,"da");
1568556b5ebSBarry Smith $                DMView(x,PETSC_VIEWER_MATLAB_WORLD);
1578556b5ebSBarry Smith $             Then from MATLAB
1588556b5ebSBarry Smith $                load('matlaboutput.mat')   % matlaboutput.mat is the default filename
1598556b5ebSBarry Smith $                xnew = zeros(da.n,da.m);
1608556b5ebSBarry Smith $                xnew(:) = x;    % reshape one dimensional vector back to two dimensions
1618556b5ebSBarry Smith 
1628556b5ebSBarry Smith               If you wish to put the same variable into the .mat file several times you need to give it a new
1638556b5ebSBarry Smith               name before each call to view.
1648556b5ebSBarry Smith 
1658556b5ebSBarry Smith               Use PetscViewerMatlabPutArray() to just put an array of doubles into the .mat file
1668556b5ebSBarry Smith 
167c2e3fba1SPatrick Sanan .seealso: `PETSC_VIEWER_MATLAB_()`, `PETSC_VIEWER_MATLAB_SELF`, `PETSC_VIEWER_MATLAB_WORLD`, `PetscViewerCreate()`,
168db781477SPatrick Sanan           `PetscViewerMatlabOpen()`, `VecView()`, `DMView()`, `PetscViewerMatlabPutArray()`, `PETSCVIEWERBINARY`, `PETSCVIEWERASCII`, `PETSCVIEWERDRAW`,
169db781477SPatrick Sanan           `PETSC_VIEWER_STDOUT_()`, `PetscViewerFileSetName()`, `PetscViewerFileSetMode()`, `PetscViewerFormat`
1708556b5ebSBarry Smith 
1718556b5ebSBarry Smith M*/
1728cc058d9SJed Brown PETSC_EXTERN PetscErrorCode PetscViewerCreate_Matlab(PetscViewer viewer)
1735c6c1daeSBarry Smith {
1745c6c1daeSBarry Smith   PetscViewer_Matlab *e;
1755c6c1daeSBarry Smith 
1765c6c1daeSBarry Smith   PetscFunctionBegin;
1779566063dSJacob Faibussowitsch   PetscCall(PetscNewLog(viewer,&e));
1789566063dSJacob Faibussowitsch   PetscCallMPI(MPI_Comm_rank(PetscObjectComm((PetscObject)viewer),&e->rank));
1797e4fd573SVaclav Hapla   e->btype     = FILE_MODE_UNDEFINED;
1805c6c1daeSBarry Smith   viewer->data = (void*) e;
181a297a907SKarl Rupp 
1829566063dSJacob Faibussowitsch   PetscCall(PetscObjectComposeFunction((PetscObject)viewer,"PetscViewerFileSetName_C",PetscViewerFileSetName_Matlab));
1839566063dSJacob Faibussowitsch   PetscCall(PetscObjectComposeFunction((PetscObject)viewer,"PetscViewerFileSetMode_C",PetscViewerFileSetMode_Matlab));
184a297a907SKarl Rupp 
1855c6c1daeSBarry Smith   viewer->ops->destroy = PetscViewerDestroy_Matlab;
1865c6c1daeSBarry Smith   PetscFunctionReturn(0);
1875c6c1daeSBarry Smith }
1885c6c1daeSBarry Smith 
1895c6c1daeSBarry Smith /*@C
1905c6c1daeSBarry Smith    PetscViewerMatlabOpen - Opens a Matlab .mat file for output
1915c6c1daeSBarry Smith 
192d083f849SBarry Smith    Collective
1935c6c1daeSBarry Smith 
1945c6c1daeSBarry Smith    Input Parameters:
1955c6c1daeSBarry Smith +  comm - MPI communicator
1965c6c1daeSBarry Smith .  name - name of file
1975c6c1daeSBarry Smith -  type - type of file
1985c6c1daeSBarry Smith $    FILE_MODE_WRITE - create new file for MATLAB output
1995c6c1daeSBarry Smith $    FILE_MODE_READ - open existing file for MATLAB input
2005c6c1daeSBarry Smith $    FILE_MODE_WRITE - open existing file for MATLAB output
2015c6c1daeSBarry Smith 
2025c6c1daeSBarry Smith    Output Parameter:
2035c6c1daeSBarry Smith .  binv - PetscViewer for MATLAB output to use with the specified file
2045c6c1daeSBarry Smith 
2055c6c1daeSBarry Smith    Level: beginner
2065c6c1daeSBarry Smith 
2075c6c1daeSBarry Smith    Note: This PetscViewer should be destroyed with PetscViewerDestroy().
2085c6c1daeSBarry Smith 
2095c6c1daeSBarry Smith     For writing files it only opens the file on processor 0 in the communicator.
2105c6c1daeSBarry Smith 
2115c6c1daeSBarry Smith      This only saves Vecs it cannot be used to save Mats. We recommend using the PETSCVIEWERBINARY to save objects to be loaded into MATLAB
2125c6c1daeSBarry Smith      instead of this routine.
2135c6c1daeSBarry Smith 
214db781477SPatrick Sanan .seealso: `PetscViewerASCIIOpen()`, `PetscViewerPushFormat()`, `PetscViewerDestroy()`, `PETSCVIEWERBINARY`, `PetscViewerBinaryOpen()`
215db781477SPatrick Sanan           `VecView()`, `MatView()`, `VecLoad()`, `MatLoad()`
2165c6c1daeSBarry Smith @*/
2175c6c1daeSBarry Smith PetscErrorCode  PetscViewerMatlabOpen(MPI_Comm comm,const char name[],PetscFileMode type,PetscViewer *binv)
2185c6c1daeSBarry Smith {
2195c6c1daeSBarry Smith   PetscFunctionBegin;
2209566063dSJacob Faibussowitsch   PetscCall(PetscViewerCreate(comm,binv));
2219566063dSJacob Faibussowitsch   PetscCall(PetscViewerSetType(*binv,PETSCVIEWERMATLAB));
2229566063dSJacob Faibussowitsch   PetscCall(PetscViewerFileSetMode(*binv,type));
2239566063dSJacob Faibussowitsch   PetscCall(PetscViewerFileSetName(*binv,name));
2245c6c1daeSBarry Smith   PetscFunctionReturn(0);
2255c6c1daeSBarry Smith }
2265c6c1daeSBarry Smith 
2275c6c1daeSBarry Smith static PetscMPIInt Petsc_Viewer_Matlab_keyval = MPI_KEYVAL_INVALID;
2285c6c1daeSBarry Smith 
2295c6c1daeSBarry Smith /*@C
2305c6c1daeSBarry Smith      PETSC_VIEWER_MATLAB_ - Creates a Matlab PetscViewer shared by all processors
2315c6c1daeSBarry Smith                      in a communicator.
2325c6c1daeSBarry Smith 
233d083f849SBarry Smith      Collective
2345c6c1daeSBarry Smith 
2355c6c1daeSBarry Smith      Input Parameter:
2365c6c1daeSBarry Smith .    comm - the MPI communicator to share the Matlab PetscViewer
2375c6c1daeSBarry Smith 
2385c6c1daeSBarry Smith      Level: intermediate
2395c6c1daeSBarry Smith 
2405c6c1daeSBarry Smith    Options Database Keys:
24110699b91SBarry Smith .    -viewer_matlab_filename <name> - name of the Matlab file
2425c6c1daeSBarry Smith 
2435c6c1daeSBarry Smith    Environmental variables:
24410699b91SBarry Smith .   PETSC_VIEWER_MATLAB_FILENAME - name of the Matlab file
2455c6c1daeSBarry Smith 
2465c6c1daeSBarry Smith      Notes:
2475c6c1daeSBarry Smith      Unlike almost all other PETSc routines, PETSC_VIEWER_MATLAB_ does not return
2485c6c1daeSBarry Smith      an error code.  The matlab PetscViewer is usually used in the form
2495c6c1daeSBarry Smith $       XXXView(XXX object,PETSC_VIEWER_MATLAB_(comm));
2505c6c1daeSBarry Smith 
2515c6c1daeSBarry Smith      Use PETSC_VIEWER_SOCKET_() or PetscViewerSocketOpen() to communicator with an interactive MATLAB session.
2525c6c1daeSBarry Smith 
253db781477SPatrick Sanan .seealso: `PETSC_VIEWER_MATLAB_WORLD`, `PETSC_VIEWER_MATLAB_SELF`, `PetscViewerMatlabOpen()`, `PetscViewerCreate()`,
254db781477SPatrick Sanan           `PetscViewerDestroy()`
2555c6c1daeSBarry Smith @*/
2565c6c1daeSBarry Smith PetscViewer  PETSC_VIEWER_MATLAB_(MPI_Comm comm)
2575c6c1daeSBarry Smith {
2585c6c1daeSBarry Smith   PetscErrorCode ierr;
2595c6c1daeSBarry Smith   PetscBool      flg;
2605c6c1daeSBarry Smith   PetscViewer    viewer;
2615c6c1daeSBarry Smith   char           fname[PETSC_MAX_PATH_LEN];
2625c6c1daeSBarry Smith   MPI_Comm       ncomm;
2635c6c1daeSBarry Smith 
2645c6c1daeSBarry Smith   PetscFunctionBegin;
265efca3c55SSatish Balay   ierr = PetscCommDuplicate(comm,&ncomm,NULL);if (ierr) {PetscError(PETSC_COMM_SELF,__LINE__,"PETSC_VIEWER_MATLAB_",__FILE__,PETSC_ERR_PLIB,PETSC_ERROR_INITIAL," ");PetscFunctionReturn(0);}
2665c6c1daeSBarry Smith   if (Petsc_Viewer_Matlab_keyval == MPI_KEYVAL_INVALID) {
26712801b39SBarry Smith     ierr = MPI_Comm_create_keyval(MPI_COMM_NULL_COPY_FN,MPI_COMM_NULL_DELETE_FN,&Petsc_Viewer_Matlab_keyval,0);
2682cb5e1ccSBarry Smith     if (ierr) {PetscError(PETSC_COMM_SELF,__LINE__,"PETSC_VIEWER_MATLAB_",__FILE__,PETSC_ERR_PLIB,PETSC_ERROR_INITIAL," ");PetscFunctionReturn(NULL);}
2695c6c1daeSBarry Smith   }
27047435625SJed Brown   ierr = MPI_Comm_get_attr(ncomm,Petsc_Viewer_Matlab_keyval,(void**)&viewer,(int*)&flg);
2712cb5e1ccSBarry Smith   if (ierr) {PetscError(PETSC_COMM_SELF,__LINE__,"PETSC_VIEWER_MATLAB_",__FILE__,PETSC_ERR_PLIB,PETSC_ERROR_INITIAL," ");PetscFunctionReturn(NULL);}
2725c6c1daeSBarry Smith   if (!flg) { /* PetscViewer not yet created */
2735c6c1daeSBarry Smith     ierr = PetscOptionsGetenv(ncomm,"PETSC_VIEWER_MATLAB_FILENAME",fname,PETSC_MAX_PATH_LEN,&flg);
2742cb5e1ccSBarry Smith     if (ierr) {PetscError(PETSC_COMM_SELF,__LINE__,"PETSC_VIEWER_MATLAB_",__FILE__,PETSC_ERR_PLIB,PETSC_ERROR_REPEAT," ");PetscFunctionReturn(NULL);}
2755c6c1daeSBarry Smith     if (!flg) {
2765c6c1daeSBarry Smith       ierr = PetscStrcpy(fname,"matlaboutput.mat");
2772cb5e1ccSBarry Smith       if (ierr) {PetscError(PETSC_COMM_SELF,__LINE__,"PETSC_VIEWER_MATLAB_",__FILE__,PETSC_ERR_PLIB,PETSC_ERROR_REPEAT," ");PetscFunctionReturn(NULL);}
2785c6c1daeSBarry Smith     }
2795c6c1daeSBarry Smith     ierr = PetscViewerMatlabOpen(ncomm,fname,FILE_MODE_WRITE,&viewer);
2802cb5e1ccSBarry Smith     if (ierr) {PetscError(PETSC_COMM_SELF,__LINE__,"PETSC_VIEWER_MATLAB_",__FILE__,PETSC_ERR_PLIB,PETSC_ERROR_REPEAT," ");PetscFunctionReturn(NULL);}
2815c6c1daeSBarry Smith     ierr = PetscObjectRegisterDestroy((PetscObject)viewer);
2822cb5e1ccSBarry Smith     if (ierr) {PetscError(PETSC_COMM_SELF,__LINE__,"PETSC_VIEWER_MATLAB_",__FILE__,PETSC_ERR_PLIB,PETSC_ERROR_REPEAT," ");PetscFunctionReturn(NULL);}
28347435625SJed Brown     ierr = MPI_Comm_set_attr(ncomm,Petsc_Viewer_Matlab_keyval,(void*)viewer);
2842cb5e1ccSBarry Smith     if (ierr) {PetscError(PETSC_COMM_SELF,__LINE__,"PETSC_VIEWER_MATLAB_",__FILE__,PETSC_ERR_PLIB,PETSC_ERROR_INITIAL," ");PetscFunctionReturn(NULL);}
2855c6c1daeSBarry Smith   }
2865c6c1daeSBarry Smith   ierr = PetscCommDestroy(&ncomm);
2872cb5e1ccSBarry Smith   if (ierr) {PetscError(PETSC_COMM_SELF,__LINE__,"PETSC_VIEWER_MATLAB_",__FILE__,PETSC_ERR_PLIB,PETSC_ERROR_REPEAT," ");PetscFunctionReturn(NULL);}
2885c6c1daeSBarry Smith   PetscFunctionReturn(viewer);
2895c6c1daeSBarry Smith }
290