xref: /petsc/src/mat/utils/matio.c (revision 4482741e5b2e2bbc854fb1f8dba65221386520f2)
1 /*$Id: matio.c,v 1.79 2001/08/06 21:16:10 bsmith Exp $*/
2 
3 /*
4    This file contains simple binary read/write routines for matrices.
5  */
6 
7 #include "src/mat/matimpl.h"             /*I  "petscmat.h"  I*/
8 #include "petscsys.h"
9 
10 #undef __FUNCT__
11 #define __FUNCT__ "MatLoadPrintHelp_Private"
12 static int MatLoadPrintHelp_Private(Mat A)
13 {
14   static PetscTruth called = PETSC_FALSE;
15   MPI_Comm          comm = A->comm;
16   int               ierr;
17 
18   PetscFunctionBegin;
19   if (called) {PetscFunctionReturn(0);} else called = PETSC_TRUE;
20   ierr = (*PetscHelpPrintf)(comm," Options for MatLoad:\n");CHKERRQ(ierr);
21   ierr = (*PetscHelpPrintf)(comm,"  -mat_type <type>\n");CHKERRQ(ierr);
22   ierr = (*PetscHelpPrintf)(comm,"  -matload_type <type>\n");CHKERRQ(ierr);
23   ierr = (*PetscHelpPrintf)(comm,"  -matload_block_size <block_size> :Used for MATBAIJ, MATBDIAG\n");CHKERRQ(ierr);
24   ierr = (*PetscHelpPrintf)(comm,"  -matload_bdiag_diags <s1,s2,s3,...> : Used for MATBDIAG\n");CHKERRQ(ierr);
25   PetscFunctionReturn(0);
26 }
27 
28 #undef __FUNCT__
29 #define __FUNCT__ "MatLoad"
30 /*@C
31    MatLoad - Loads a matrix that has been stored in binary format
32    with MatView().  The matrix format is determined from the options database.
33    Generates a parallel MPI matrix if the communicator has more than one
34    processor.  The default matrix type is AIJ.
35 
36    Collective on PetscViewer
37 
38    Input Parameters:
39 +  viewer - binary file viewer, created with PetscViewerBinaryOpen()
40 -  outtype - type of matrix desired, for example MATSEQAIJ,
41              MATMPIROWBS, etc.  See types in petsc/include/petscmat.h.
42 
43    Output Parameters:
44 .  newmat - new matrix
45 
46    Basic Options Database Keys:
47 +    -matload_type seqaij   - AIJ type
48 .    -matload_type mpiaij   - parallel AIJ type
49 .    -matload_type seqbaij  - block AIJ type
50 .    -matload_type mpibaij  - parallel block AIJ type
51 .    -matload_type seqsbaij - block symmetric AIJ type
52 .    -matload_type mpisbaij - parallel block symmetric AIJ type
53 .    -matload_type seqbdiag - block diagonal type
54 .    -matload_type mpibdiag - parallel block diagonal type
55 .    -matload_type mpirowbs - parallel rowbs type
56 .    -matload_type seqdense - dense type
57 .    -matload_type mpidense - parallel dense type
58 -    -matload_symmetric - matrix in file is symmetric
59 
60    More Options Database Keys:
61    Used with block matrix formats (MATSEQBAIJ, MATMPIBDIAG, ...) to specify
62    block size
63 .    -matload_block_size <bs>
64 
65    Used to specify block diagonal numbers for MATSEQBDIAG and MATMPIBDIAG formats
66 .    -matload_bdiag_diags <s1,s2,s3,...>
67 
68    Level: beginner
69 
70    Notes:
71    MatLoad() automatically loads into the options database any options
72    given in the file filename.info where filename is the name of the file
73    that was passed to the PetscViewerBinaryOpen(). The options in the info
74    file will be ignored if you use the -matload_ignore_info option.
75 
76    In parallel, each processor can load a subset of rows (or the
77    entire matrix).  This routine is especially useful when a large
78    matrix is stored on disk and only part of it existsis desired on each
79    processor.  For example, a parallel solver may access only some of
80    the rows from each processor.  The algorithm used here reads
81    relatively small blocks of data rather than reading the entire
82    matrix and then subsetting it.
83 
84    Notes for advanced users:
85    Most users should not need to know the details of the binary storage
86    format, since MatLoad() and MatView() completely hide these details.
87    But for anyone who's interested, the standard binary matrix storage
88    format is
89 
90 $    int    MAT_FILE_COOKIE
91 $    int    number of rows
92 $    int    number of columns
93 $    int    total number of nonzeros
94 $    int    *number nonzeros in each row
95 $    int    *column indices of all nonzeros (starting index is zero)
96 $    PetscScalar *values of all nonzeros
97 
98    Note for Cray users, the int's stored in the binary file are 32 bit
99 integers; not 64 as they are represented in the memory, so if you
100 write your own routines to read/write these binary files from the Cray
101 you need to adjust the integer sizes that you read in, see
102 PetscReadBinary() and PetscWriteBinary() to see how this may be
103 done.
104 
105    In addition, PETSc automatically does the byte swapping for
106 machines that store the bytes reversed, e.g.  DEC alpha, freebsd,
107 linux, nt and the paragon; thus if you write your own binary
108 read/write routines you have to swap the bytes; see PetscReadBinary()
109 and PetscWriteBinary() to see how this may be done.
110 
111 .keywords: matrix, load, binary, input
112 
113 .seealso: PetscViewerBinaryOpen(), MatView(), VecLoad()
114 
115  @*/
116 int MatLoad(PetscViewer viewer,const MatType outtype,Mat *newmat)
117 {
118   Mat         factory;
119   int         ierr;
120   PetscTruth  isbinary,flg;
121   MPI_Comm    comm;
122   int         (*r)(PetscViewer,const MatType,Mat*);
123   char        mtype[256],*prefix;
124 
125   PetscFunctionBegin;
126   PetscValidHeaderSpecific(viewer,PETSC_VIEWER_COOKIE,1);
127   PetscValidPointer(newmat,3);
128   *newmat = 0;
129 
130   ierr = PetscObjectGetOptionsPrefix((PetscObject)viewer,&prefix);CHKERRQ(ierr);
131   ierr = PetscTypeCompare((PetscObject)viewer,PETSC_VIEWER_BINARY,&isbinary);CHKERRQ(ierr);
132   if (!isbinary) {
133     SETERRQ(PETSC_ERR_ARG_WRONG,"Invalid viewer; open viewer with PetscViewerBinaryOpen()");
134   }
135 
136   ierr = PetscOptionsGetString(prefix,"-mat_type",mtype,256,&flg);CHKERRQ(ierr);
137   if (flg) {
138     outtype = mtype;
139   }
140   ierr = PetscOptionsGetString(prefix,"-matload_type",mtype,256,&flg);CHKERRQ(ierr);
141   if (flg) {
142     outtype = mtype;
143   }
144   if (!outtype) outtype = MATAIJ;
145 
146   ierr = PetscObjectGetComm((PetscObject)viewer,&comm);CHKERRQ(ierr);
147   ierr = MatCreate(comm,0,0,0,0,&factory);CHKERRQ(ierr);
148   ierr = MatSetType(factory,outtype);CHKERRQ(ierr);
149   r = factory->ops->load;
150   ierr = MatDestroy(factory);
151   if (!r) SETERRQ1(PETSC_ERR_SUP,"MatLoad is not supported for type: %s",outtype);
152 
153   ierr = PetscLogEventBegin(MAT_Load,viewer,0,0,0);CHKERRQ(ierr);
154   ierr = (*r)(viewer,outtype,newmat);CHKERRQ(ierr);
155   ierr = PetscLogEventEnd(MAT_Load,viewer,0,0,0);CHKERRQ(ierr);
156 
157   ierr = PetscOptionsHasName(prefix,"-matload_symmetric",&flg);CHKERRQ(ierr);
158   if (flg) {
159     ierr = MatSetOption(*newmat,MAT_SYMMETRIC);CHKERRQ(ierr);
160     ierr = MatSetOption(*newmat,MAT_SYMMETRY_ETERNAL);CHKERRQ(ierr);
161   }
162   ierr = PetscOptionsHasName(PETSC_NULL,"-help",&flg);CHKERRQ(ierr);
163   if (flg) {ierr = MatLoadPrintHelp_Private(*newmat);CHKERRQ(ierr); }
164   PetscFunctionReturn(0);
165 }
166 
167