Actual source code: ex78.c
2: static char help[] = "Reads in a matrix in ASCII MATLAB format (I,J,A), read in vectors rhs and exact_solu in ASCII format.\n\
3: Writes them using the PETSc sparse format.\n\
4: Note: I and J start at 1, not 0, use -noshift if indices in file start with zero!\n\
5: Input parameters are:\n\
6: -Ain <filename> : input matrix in ascii format\n\
7: -rhs <filename> : input rhs in ascii format\n\
8: -solu <filename> : input true solution in ascii format\n\\n";
10: /*
11: Example: ./ex78 -Ain Ain -rhs rhs -solu solu -noshift -mat_view
12: with the datafiles in the following format:
13: Ain (I and J start at 0):
14: ------------------------
15: 3 3 6
16: 0 0 1.0
17: 0 1 2.0
18: 1 0 3.0
19: 1 1 4.0
20: 1 2 5.0
21: 2 2 6.0
23: rhs
24: ---
25: 0 3.0
26: 1 12.0
27: 2 6.0
29: solu
30: ----
31: 0 1.0
32: 0 1.0
33: 0 1.0
34: */
36: #include <petscmat.h>
38: int main(int argc, char **args)
39: {
40: Mat A = NULL;
41: Vec b, u = NULL, u_tmp;
42: char Ain[PETSC_MAX_PATH_LEN], rhs[PETSC_MAX_PATH_LEN], solu[PETSC_MAX_PATH_LEN];
43: int m, n = 0, nz, dummy; /* these are fscaned so kept as int */
44: PetscInt i, col, row, shift = 1, sizes[3], nsizes;
45: PetscScalar val;
46: PetscReal res_norm;
47: FILE *Afile, *bfile, *ufile;
48: PetscViewer view;
49: PetscBool flg_A, flg_b, flg_u, flg;
50: PetscMPIInt size;
52: PetscFunctionBeginUser;
53: PetscCall(PetscInitialize(&argc, &args, (char *)0, help));
54: PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size));
55: PetscCheck(size == 1, PETSC_COMM_WORLD, PETSC_ERR_WRONG_MPI_SIZE, "This is a uniprocessor example only!");
57: /* Read in matrix, rhs and exact solution from ascii files */
58: PetscCall(PetscOptionsGetString(NULL, NULL, "-Ain", Ain, sizeof(Ain), &flg_A));
59: PetscCall(PetscOptionsHasName(NULL, NULL, "-noshift", &flg));
60: if (flg) shift = 0;
61: if (flg_A) {
62: PetscCall(PetscPrintf(PETSC_COMM_SELF, "\n Read matrix in ascii format ...\n"));
63: PetscCall(PetscFOpen(PETSC_COMM_SELF, Ain, "r", &Afile));
64: nsizes = 3;
65: PetscCall(PetscOptionsGetIntArray(NULL, NULL, "-nosizesinfile", sizes, &nsizes, &flg));
66: if (flg) {
67: PetscCheck(nsizes == 3, PETSC_COMM_WORLD, PETSC_ERR_USER, "Must pass in three m,n,nz as arguments for -nosizesinfile");
68: m = sizes[0];
69: n = sizes[1];
70: nz = sizes[2];
71: } else {
72: PetscCheck(fscanf(Afile, "%d %d %d\n", &m, &n, &nz) == 3, PETSC_COMM_SELF, PETSC_ERR_FILE_UNEXPECTED, "Badly formatted input file");
73: }
74: PetscCall(PetscPrintf(PETSC_COMM_SELF, "m: %d, n: %d, nz: %d \n", m, n, nz));
75: PetscCheck(m == n, PETSC_COMM_SELF, PETSC_ERR_ARG_SIZ, "Number of rows, cols must be same for this example");
76: PetscCall(MatCreate(PETSC_COMM_SELF, &A));
77: PetscCall(MatSetSizes(A, PETSC_DECIDE, PETSC_DECIDE, m, n));
78: PetscCall(MatSetFromOptions(A));
79: PetscCall(MatSeqAIJSetPreallocation(A, nz / m, NULL));
80: PetscCall(MatSetOption(A, MAT_NEW_NONZERO_ALLOCATION_ERR, PETSC_FALSE));
82: for (i = 0; i < nz; i++) {
83: PetscCheck(fscanf(Afile, "%d %d %le\n", &row, &col, (double *)&val) == 3, PETSC_COMM_SELF, PETSC_ERR_FILE_UNEXPECTED, "Badly formatted input file");
84: row -= shift;
85: col -= shift; /* set index set starts at 0 */
86: PetscCall(MatSetValues(A, 1, &row, 1, &col, &val, INSERT_VALUES));
87: }
88: PetscCall(MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY));
89: PetscCall(MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY));
90: fclose(Afile);
91: }
93: PetscCall(PetscOptionsGetString(NULL, NULL, "-rhs", rhs, sizeof(rhs), &flg_b));
94: if (flg_b) {
95: PetscCall(VecCreate(PETSC_COMM_SELF, &b));
96: PetscCall(VecSetSizes(b, PETSC_DECIDE, n));
97: PetscCall(VecSetFromOptions(b));
98: PetscCall(PetscPrintf(PETSC_COMM_SELF, "\n Read rhs in ascii format ...\n"));
99: PetscCall(PetscFOpen(PETSC_COMM_SELF, rhs, "r", &bfile));
100: for (i = 0; i < n; i++) {
101: PetscCheck(fscanf(bfile, "%d %le\n", &dummy, (double *)&val) == 2, PETSC_COMM_SELF, PETSC_ERR_FILE_UNEXPECTED, "Badly formatted input file");
102: PetscCall(VecSetValues(b, 1, &i, &val, INSERT_VALUES));
103: }
104: PetscCall(VecAssemblyBegin(b));
105: PetscCall(VecAssemblyEnd(b));
106: fclose(bfile);
107: }
109: PetscCall(PetscOptionsGetString(NULL, NULL, "-solu", solu, sizeof(solu), &flg_u));
110: if (flg_u) {
111: PetscCall(VecCreate(PETSC_COMM_SELF, &u));
112: PetscCall(VecSetSizes(u, PETSC_DECIDE, n));
113: PetscCall(VecSetFromOptions(u));
114: PetscCall(PetscPrintf(PETSC_COMM_SELF, "\n Read exact solution in ascii format ...\n"));
115: PetscCall(PetscFOpen(PETSC_COMM_SELF, solu, "r", &ufile));
116: for (i = 0; i < n; i++) {
117: PetscCheck(fscanf(ufile, "%d %le\n", &dummy, (double *)&val) == 2, PETSC_COMM_SELF, PETSC_ERR_FILE_UNEXPECTED, "Badly formatted input file");
118: PetscCall(VecSetValues(u, 1, &i, &val, INSERT_VALUES));
119: }
120: PetscCall(VecAssemblyBegin(u));
121: PetscCall(VecAssemblyEnd(u));
122: fclose(ufile);
123: }
125: /* Write matrix, rhs and exact solution in Petsc binary file */
126: PetscCall(PetscPrintf(PETSC_COMM_SELF, "\n Write matrix in binary to 'matrix.dat' ...\n"));
127: PetscCall(PetscViewerBinaryOpen(PETSC_COMM_SELF, "matrix.dat", FILE_MODE_WRITE, &view));
128: PetscCall(MatView(A, view));
130: if (flg_b) { /* Write rhs in Petsc binary file */
131: PetscCall(PetscPrintf(PETSC_COMM_SELF, "\n Write rhs in binary to 'matrix.dat' ...\n"));
132: PetscCall(VecView(b, view));
133: }
134: if (flg_u) {
135: PetscCall(PetscPrintf(PETSC_COMM_SELF, "\n Write exact solution in binary to 'matrix.dat' ...\n"));
136: PetscCall(VecView(u, view));
137: }
139: /* Check accuracy of the data */
140: if (flg_A & flg_b & flg_u) {
141: PetscCall(VecDuplicate(u, &u_tmp));
142: PetscCall(MatMult(A, u, u_tmp));
143: PetscCall(VecAXPY(u_tmp, -1.0, b));
144: PetscCall(VecNorm(u_tmp, NORM_2, &res_norm));
145: PetscCall(PetscPrintf(PETSC_COMM_SELF, "\n Accuracy of the reading data: | b - A*u |_2 : %g \n", res_norm));
146: PetscCall(VecDestroy(&u_tmp));
147: }
149: PetscCall(MatDestroy(&A));
150: if (flg_b) PetscCall(VecDestroy(&b));
151: if (flg_u) PetscCall(VecDestroy(&u));
152: PetscCall(PetscViewerDestroy(&view));
153: PetscCall(PetscFinalize());
154: return 0;
155: }
157: /*TEST
159: build:
160: requires: !defined(PETSC_USE_64BIT_INDICES) double !complex
162: test:
163: requires: datafilespath
164: args: -Ain ${DATAFILESPATH}/matrices/indefinite/afiro_A.dat
166: TEST*/