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