xref: /petsc/src/mat/tests/ex245.c (revision d5b43468fb8780a8feea140ccd6fa3e6a50411cc)
1 
2 static char help[] = "Tests LU, Cholesky factorization and MatMatSolve() for a ScaLAPACK dense matrix.\n\n";
3 
4 #include <petscmat.h>
5 
6 int main(int argc, char **argv)
7 {
8   Mat             A, F, B, X, C, Aher, G;
9   Vec             b, x, c, d, e;
10   PetscInt        m = 5, n, p, i, j, nrows, ncols;
11   PetscScalar    *v, *barray, rval;
12   PetscReal       norm, tol = 1.e5 * PETSC_MACHINE_EPSILON;
13   PetscMPIInt     size, rank;
14   PetscRandom     rand;
15   const PetscInt *rows, *cols;
16   IS              isrows, iscols;
17   PetscBool       mats_view = PETSC_FALSE;
18 
19   PetscFunctionBeginUser;
20   PetscCall(PetscInitialize(&argc, &argv, (char *)0, help));
21   PetscCallMPI(MPI_Comm_rank(PETSC_COMM_WORLD, &rank));
22   PetscCallMPI(MPI_Comm_size(PETSC_COMM_WORLD, &size));
23 
24   PetscCall(PetscRandomCreate(PETSC_COMM_WORLD, &rand));
25   PetscCall(PetscRandomSetFromOptions(rand));
26 
27   /* Get local dimensions of matrices */
28   PetscCall(PetscOptionsGetInt(NULL, NULL, "-m", &m, NULL));
29   n = m;
30   PetscCall(PetscOptionsGetInt(NULL, NULL, "-n", &n, NULL));
31   p = m / 2;
32   PetscCall(PetscOptionsGetInt(NULL, NULL, "-p", &p, NULL));
33   PetscCall(PetscOptionsHasName(NULL, NULL, "-mats_view", &mats_view));
34 
35   /* Create matrix A */
36   PetscCall(PetscPrintf(PETSC_COMM_WORLD, " Create ScaLAPACK matrix A\n"));
37   PetscCall(MatCreate(PETSC_COMM_WORLD, &A));
38   PetscCall(MatSetSizes(A, m, n, PETSC_DECIDE, PETSC_DECIDE));
39   PetscCall(MatSetType(A, MATSCALAPACK));
40   PetscCall(MatSetFromOptions(A));
41   PetscCall(MatSetUp(A));
42   /* Set local matrix entries */
43   PetscCall(MatGetOwnershipIS(A, &isrows, &iscols));
44   PetscCall(ISGetLocalSize(isrows, &nrows));
45   PetscCall(ISGetIndices(isrows, &rows));
46   PetscCall(ISGetLocalSize(iscols, &ncols));
47   PetscCall(ISGetIndices(iscols, &cols));
48   PetscCall(PetscMalloc1(nrows * ncols, &v));
49   for (i = 0; i < nrows; i++) {
50     for (j = 0; j < ncols; j++) {
51       PetscCall(PetscRandomGetValue(rand, &rval));
52       v[i * ncols + j] = rval;
53     }
54   }
55   PetscCall(MatSetValues(A, nrows, rows, ncols, cols, v, INSERT_VALUES));
56   PetscCall(MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY));
57   PetscCall(MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY));
58   PetscCall(ISRestoreIndices(isrows, &rows));
59   PetscCall(ISRestoreIndices(iscols, &cols));
60   PetscCall(ISDestroy(&isrows));
61   PetscCall(ISDestroy(&iscols));
62   PetscCall(PetscFree(v));
63   if (mats_view) {
64     PetscCall(PetscPrintf(PETSC_COMM_WORLD, "A: nrows %" PetscInt_FMT ", m %" PetscInt_FMT "; ncols %" PetscInt_FMT ", n %" PetscInt_FMT "\n", nrows, m, ncols, n));
65     PetscCall(MatView(A, PETSC_VIEWER_STDOUT_WORLD));
66   }
67 
68   /* Create rhs matrix B */
69   PetscCall(PetscPrintf(PETSC_COMM_WORLD, " Create rhs matrix B\n"));
70   PetscCall(MatCreate(PETSC_COMM_WORLD, &B));
71   PetscCall(MatSetSizes(B, m, p, PETSC_DECIDE, PETSC_DECIDE));
72   PetscCall(MatSetType(B, MATSCALAPACK));
73   PetscCall(MatSetFromOptions(B));
74   PetscCall(MatSetUp(B));
75   PetscCall(MatGetOwnershipIS(B, &isrows, &iscols));
76   PetscCall(ISGetLocalSize(isrows, &nrows));
77   PetscCall(ISGetIndices(isrows, &rows));
78   PetscCall(ISGetLocalSize(iscols, &ncols));
79   PetscCall(ISGetIndices(iscols, &cols));
80   PetscCall(PetscMalloc1(nrows * ncols, &v));
81   for (i = 0; i < nrows; i++) {
82     for (j = 0; j < ncols; j++) {
83       PetscCall(PetscRandomGetValue(rand, &rval));
84       v[i * ncols + j] = rval;
85     }
86   }
87   PetscCall(MatSetValues(B, nrows, rows, ncols, cols, v, INSERT_VALUES));
88   PetscCall(MatAssemblyBegin(B, MAT_FINAL_ASSEMBLY));
89   PetscCall(MatAssemblyEnd(B, MAT_FINAL_ASSEMBLY));
90   PetscCall(ISRestoreIndices(isrows, &rows));
91   PetscCall(ISRestoreIndices(iscols, &cols));
92   PetscCall(ISDestroy(&isrows));
93   PetscCall(ISDestroy(&iscols));
94   PetscCall(PetscFree(v));
95   if (mats_view) {
96     PetscCall(PetscPrintf(PETSC_COMM_WORLD, "B: nrows %" PetscInt_FMT ", m %" PetscInt_FMT "; ncols %" PetscInt_FMT ", p %" PetscInt_FMT "\n", nrows, m, ncols, p));
97     PetscCall(MatView(B, PETSC_VIEWER_STDOUT_WORLD));
98   }
99 
100   /* Create rhs vector b and solution x (same size as b) */
101   PetscCall(VecCreate(PETSC_COMM_WORLD, &b));
102   PetscCall(VecSetSizes(b, m, PETSC_DECIDE));
103   PetscCall(VecSetFromOptions(b));
104   PetscCall(VecGetArray(b, &barray));
105   for (j = 0; j < m; j++) {
106     PetscCall(PetscRandomGetValue(rand, &rval));
107     barray[j] = rval;
108   }
109   PetscCall(VecRestoreArray(b, &barray));
110   PetscCall(VecAssemblyBegin(b));
111   PetscCall(VecAssemblyEnd(b));
112   if (mats_view) {
113     PetscCall(PetscSynchronizedPrintf(PETSC_COMM_WORLD, "[%d] b: m %" PetscInt_FMT "\n", rank, m));
114     PetscCall(PetscSynchronizedFlush(PETSC_COMM_WORLD, PETSC_STDOUT));
115     PetscCall(VecView(b, PETSC_VIEWER_STDOUT_WORLD));
116   }
117   PetscCall(VecDuplicate(b, &x));
118 
119   /* Create matrix X - same size as B */
120   PetscCall(PetscPrintf(PETSC_COMM_WORLD, " Create solution matrix X\n"));
121   PetscCall(MatDuplicate(B, MAT_DO_NOT_COPY_VALUES, &X));
122 
123   /* Cholesky factorization */
124   /*------------------------*/
125   PetscCall(PetscPrintf(PETSC_COMM_WORLD, " Create ScaLAPACK matrix Aher\n"));
126   PetscCall(MatHermitianTranspose(A, MAT_INITIAL_MATRIX, &Aher));
127   PetscCall(MatAXPY(Aher, 1.0, A, SAME_NONZERO_PATTERN)); /* Aher = A + A^T */
128   PetscCall(MatShift(Aher, 100.0));                       /* add 100.0 to diagonals of Aher to make it spd */
129   if (mats_view) {
130     PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Aher:\n"));
131     PetscCall(MatView(Aher, PETSC_VIEWER_STDOUT_WORLD));
132   }
133 
134   /* Cholesky factorization */
135   /*------------------------*/
136   PetscCall(PetscPrintf(PETSC_COMM_WORLD, " Test Cholesky Solver \n"));
137   /* In-place Cholesky */
138   /* Create matrix factor G, with a copy of Aher */
139   PetscCall(MatDuplicate(Aher, MAT_COPY_VALUES, &G));
140 
141   /* G = L * L^T */
142   PetscCall(MatCholeskyFactor(G, 0, 0));
143   if (mats_view) {
144     PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Cholesky Factor G:\n"));
145     PetscCall(MatView(G, PETSC_VIEWER_STDOUT_WORLD));
146   }
147 
148   /* Solve L * L^T x = b and L * L^T * X = B */
149   PetscCall(MatSolve(G, b, x));
150   PetscCall(MatMatSolve(G, B, X));
151   PetscCall(MatDestroy(&G));
152 
153   /* Out-place Cholesky */
154   PetscCall(MatGetFactor(Aher, MATSOLVERSCALAPACK, MAT_FACTOR_CHOLESKY, &G));
155   PetscCall(MatCholeskyFactorSymbolic(G, Aher, 0, NULL));
156   PetscCall(MatCholeskyFactorNumeric(G, Aher, NULL));
157   if (mats_view) PetscCall(MatView(G, PETSC_VIEWER_STDOUT_WORLD));
158   PetscCall(MatSolve(G, b, x));
159   PetscCall(MatMatSolve(G, B, X));
160   PetscCall(MatDestroy(&G));
161 
162   /* Check norm(Aher*x - b) */
163   PetscCall(VecCreate(PETSC_COMM_WORLD, &c));
164   PetscCall(VecSetSizes(c, m, PETSC_DECIDE));
165   PetscCall(VecSetFromOptions(c));
166   PetscCall(MatMult(Aher, x, c));
167   PetscCall(VecAXPY(c, -1.0, b));
168   PetscCall(VecNorm(c, NORM_1, &norm));
169   if (norm > tol) PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Warning: ||Aher*x - b||=%g for Cholesky\n", (double)norm));
170 
171   /* Check norm(Aher*X - B) */
172   PetscCall(MatMatMult(Aher, X, MAT_INITIAL_MATRIX, PETSC_DEFAULT, &C));
173   PetscCall(MatAXPY(C, -1.0, B, SAME_NONZERO_PATTERN));
174   PetscCall(MatNorm(C, NORM_1, &norm));
175   if (norm > tol) PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Warning: ||Aher*X - B||=%g for Cholesky\n", (double)norm));
176 
177   /* LU factorization */
178   /*------------------*/
179   PetscCall(PetscPrintf(PETSC_COMM_WORLD, " Test LU Solver \n"));
180   /* In-place LU */
181   /* Create matrix factor F, with a copy of A */
182   PetscCall(MatDuplicate(A, MAT_COPY_VALUES, &F));
183   /* Create vector d to test MatSolveAdd() */
184   PetscCall(VecDuplicate(x, &d));
185   PetscCall(VecCopy(x, d));
186 
187   /* PF=LU factorization */
188   PetscCall(MatLUFactor(F, 0, 0, NULL));
189 
190   /* Solve LUX = PB */
191   PetscCall(MatSolveAdd(F, b, d, x));
192   PetscCall(MatMatSolve(F, B, X));
193   PetscCall(MatDestroy(&F));
194 
195   /* Check norm(A*X - B) */
196   PetscCall(VecCreate(PETSC_COMM_WORLD, &e));
197   PetscCall(VecSetSizes(e, m, PETSC_DECIDE));
198   PetscCall(VecSetFromOptions(e));
199   PetscCall(MatMult(A, x, c));
200   PetscCall(MatMult(A, d, e));
201   PetscCall(VecAXPY(c, -1.0, e));
202   PetscCall(VecAXPY(c, -1.0, b));
203   PetscCall(VecNorm(c, NORM_1, &norm));
204   if (norm > tol) PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Warning: ||A*x - b||=%g for LU\n", (double)norm));
205   /* Reuse product C; replace Aher with A */
206   PetscCall(MatProductReplaceMats(A, NULL, NULL, C));
207   PetscCall(MatMatMult(A, X, MAT_REUSE_MATRIX, PETSC_DEFAULT, &C));
208   PetscCall(MatAXPY(C, -1.0, B, SAME_NONZERO_PATTERN));
209   PetscCall(MatNorm(C, NORM_1, &norm));
210   if (norm > tol) PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Warning: ||A*X - B||=%g for LU\n", (double)norm));
211 
212   /* Out-place LU */
213   PetscCall(MatGetFactor(A, MATSOLVERSCALAPACK, MAT_FACTOR_LU, &F));
214   PetscCall(MatLUFactorSymbolic(F, A, 0, 0, NULL));
215   PetscCall(MatLUFactorNumeric(F, A, NULL));
216   if (mats_view) PetscCall(MatView(F, PETSC_VIEWER_STDOUT_WORLD));
217   PetscCall(MatSolve(F, b, x));
218   PetscCall(MatMatSolve(F, B, X));
219   PetscCall(MatDestroy(&F));
220 
221   /* Free space */
222   PetscCall(MatDestroy(&A));
223   PetscCall(MatDestroy(&Aher));
224   PetscCall(MatDestroy(&B));
225   PetscCall(MatDestroy(&C));
226   PetscCall(MatDestroy(&X));
227   PetscCall(VecDestroy(&b));
228   PetscCall(VecDestroy(&c));
229   PetscCall(VecDestroy(&d));
230   PetscCall(VecDestroy(&e));
231   PetscCall(VecDestroy(&x));
232   PetscCall(PetscRandomDestroy(&rand));
233   PetscCall(PetscFinalize());
234   return 0;
235 }
236 
237 /*TEST
238 
239    build:
240       requires: scalapack
241 
242    test:
243       nsize: 2
244       output_file: output/ex245.out
245 
246    test:
247       suffix: 2
248       nsize: 6
249       output_file: output/ex245.out
250 
251 TEST*/
252