Actual source code: ex195.c

  1: /*
  2:  * ex195.c
  3:  *
  4:  *  Created on: Aug 24, 2015
  5:  *      Author: Fande Kong <fdkong.jd@gmail.com>
  6:  */

  8: static char help[] = " Demonstrate the use of MatConvert_Nest_AIJ\n";

 10: #include <petscmat.h>

 12: int main(int argc, char **args)
 13: {
 14:   Mat         A1, A2, A3, A4, A5, B, C, C1, nest;
 15:   Mat         aij;
 16:   MPI_Comm    comm;
 17:   PetscInt    m, M, n, istart, iend, ii, i, J, j, K = 10;
 18:   PetscScalar v;
 19:   PetscMPIInt size;
 20:   PetscBool   equal, test = PETSC_FALSE, test_null = PETSC_FALSE;

 22:   PetscFunctionBeginUser;
 23:   PetscCall(PetscInitialize(&argc, &args, NULL, help));
 24:   comm = PETSC_COMM_WORLD;
 25:   PetscCallMPI(MPI_Comm_size(comm, &size));

 27:   /*
 28:      Assemble the matrix for the five point stencil, YET AGAIN
 29:   */
 30:   PetscCall(MatCreate(comm, &A1));
 31:   m = 2, n = 2;
 32:   PetscCall(MatSetSizes(A1, PETSC_DECIDE, PETSC_DECIDE, m * n, m * n));
 33:   PetscCall(MatSetFromOptions(A1));
 34:   PetscCall(MatSetUp(A1));
 35:   PetscCall(MatGetOwnershipRange(A1, &istart, &iend));
 36:   for (ii = istart; ii < iend; ii++) {
 37:     v = -1.0;
 38:     i = ii / n;
 39:     j = ii - i * n;
 40:     if (i > 0) {
 41:       J = ii - n;
 42:       PetscCall(MatSetValues(A1, 1, &ii, 1, &J, &v, INSERT_VALUES));
 43:     }
 44:     if (i < m - 1) {
 45:       J = ii + n;
 46:       PetscCall(MatSetValues(A1, 1, &ii, 1, &J, &v, INSERT_VALUES));
 47:     }
 48:     if (j > 0) {
 49:       J = ii - 1;
 50:       PetscCall(MatSetValues(A1, 1, &ii, 1, &J, &v, INSERT_VALUES));
 51:     }
 52:     if (j < n - 1) {
 53:       J = ii + 1;
 54:       PetscCall(MatSetValues(A1, 1, &ii, 1, &J, &v, INSERT_VALUES));
 55:     }
 56:     v = 4.0;
 57:     PetscCall(MatSetValues(A1, 1, &ii, 1, &ii, &v, INSERT_VALUES));
 58:   }
 59:   PetscCall(MatAssemblyBegin(A1, MAT_FINAL_ASSEMBLY));
 60:   PetscCall(MatAssemblyEnd(A1, MAT_FINAL_ASSEMBLY));
 61:   PetscCall(MatView(A1, PETSC_VIEWER_STDOUT_WORLD));

 63:   PetscCall(MatDuplicate(A1, MAT_COPY_VALUES, &A2));
 64:   PetscCall(MatDuplicate(A1, MAT_COPY_VALUES, &A3));
 65:   PetscCall(MatDuplicate(A1, MAT_COPY_VALUES, &A4));

 67:   /* create a nest matrix */
 68:   PetscCall(MatCreate(comm, &nest));
 69:   PetscCall(MatSetType(nest, MATNEST));
 70:   PetscCall(PetscOptionsGetBool(NULL, NULL, "-test_null", &test_null, NULL));
 71:   if (test_null) {
 72:     IS       is[2];
 73:     PetscInt st;

 75:     PetscCall(MatGetLocalSize(A1, &m, NULL));
 76:     PetscCall(MatGetOwnershipRange(A1, &st, NULL));
 77:     PetscCall(ISCreateStride(comm, m, st, 2, &is[0]));
 78:     PetscCall(ISCreateStride(comm, m, st + 1, 2, &is[1]));
 79:     PetscCall(MatNestSetSubMats(nest, 2, is, 2, is, NULL));
 80:     PetscCall(ISDestroy(&is[0]));
 81:     PetscCall(ISDestroy(&is[1]));
 82:   } else {
 83:     Mat mata[] = {A1, A2, A3, A4};

 85:     PetscCall(MatNestSetSubMats(nest, 2, NULL, 2, NULL, mata));
 86:   }
 87:   PetscCall(MatSetUp(nest));

 89:   /* test matrix product error messages */
 90:   PetscCall(PetscOptionsGetBool(NULL, NULL, "-test_nest*nest", &test, NULL));
 91:   if (test) PetscCall(MatMatMult(nest, nest, MAT_INITIAL_MATRIX, PETSC_DETERMINE, &C));

 93:   PetscCall(PetscOptionsGetBool(NULL, NULL, "-test_matproductsetfromoptions", &test, NULL));
 94:   if (test) {
 95:     PetscCall(MatProductCreate(nest, nest, NULL, &C));
 96:     PetscCall(MatProductSetType(C, MATPRODUCT_AB));
 97:     PetscCall(MatProductSymbolic(C));
 98:   }

100:   PetscCall(PetscOptionsGetBool(NULL, NULL, "-test_matproductsymbolic", &test, NULL));
101:   if (test) {
102:     PetscCall(MatProductCreate(nest, nest, NULL, &C));
103:     PetscCall(MatProductSetType(C, MATPRODUCT_AB));
104:     PetscCall(MatProductSetFromOptions(C));
105:     PetscCall(MatProductSymbolic(C));
106:   }

108:   PetscCall(MatConvert(nest, MATAIJ, MAT_INITIAL_MATRIX, &aij));
109:   PetscCall(MatView(aij, PETSC_VIEWER_STDOUT_WORLD));

111:   /* create a dense matrix */
112:   PetscCall(MatGetSize(nest, &M, NULL));
113:   PetscCall(MatGetLocalSize(nest, &m, NULL));
114:   PetscCall(MatCreateDense(comm, m, PETSC_DECIDE, M, K, NULL, &B));
115:   PetscCall(MatSetRandom(B, NULL));

117:   /* C = nest*B_dense */
118:   PetscCall(MatMatMult(nest, B, MAT_INITIAL_MATRIX, PETSC_DETERMINE, &C));
119:   PetscCall(MatMatMult(nest, B, MAT_REUSE_MATRIX, PETSC_DETERMINE, &C));
120:   PetscCall(MatMatMultEqual(nest, B, C, 10, &equal));
121:   PetscCheck(equal, PETSC_COMM_WORLD, PETSC_ERR_PLIB, "Error in C != nest*B_dense");

123:   /* Test B = nest*C, reuse C and B with MatProductCreateWithMat() */
124:   /* C has been obtained from nest*B. Clear internal data structures related to factors to prevent circular references */
125:   PetscCall(MatProductClear(C));
126:   PetscCall(MatProductCreateWithMat(nest, C, NULL, B));
127:   PetscCall(MatProductSetType(B, MATPRODUCT_AB));
128:   PetscCall(MatProductSetFromOptions(B));
129:   PetscCall(MatProductSymbolic(B));
130:   PetscCall(MatProductNumeric(B));
131:   PetscCall(MatMatMultEqual(nest, C, B, 10, &equal));
132:   PetscCheck(equal, PETSC_COMM_WORLD, PETSC_ERR_PLIB, "Error in B != nest*C_dense");
133:   PetscCall(MatConvert(nest, MATAIJ, MAT_INPLACE_MATRIX, &nest));
134:   PetscCall(MatEqual(nest, aij, &equal));
135:   PetscCheck(equal, PETSC_COMM_WORLD, PETSC_ERR_PLIB, "Error in aij != nest");

137:   /* Test with virtual block */
138:   PetscCall(MatCreateTranspose(A1, &A5)); /* A1 is symmetric */
139:   PetscCall(MatNestSetSubMat(nest, 0, 0, A5));
140:   PetscCall(MatMatMult(nest, B, MAT_INITIAL_MATRIX, PETSC_DETERMINE, &C1));
141:   PetscCall(MatMatMult(nest, B, MAT_REUSE_MATRIX, PETSC_DETERMINE, &C1));
142:   PetscCall(MatMatMultEqual(nest, B, C1, 10, &equal));
143:   PetscCheck(equal, PETSC_COMM_WORLD, PETSC_ERR_PLIB, "Error in C1 != C");
144:   PetscCall(MatDestroy(&C1));
145:   PetscCall(MatDestroy(&A5));

147:   PetscCall(MatDestroy(&nest));
148:   PetscCall(MatDestroy(&C));
149:   PetscCall(MatDestroy(&B));
150:   PetscCall(MatDestroy(&aij));
151:   PetscCall(MatDestroy(&A1));
152:   PetscCall(MatDestroy(&A2));
153:   PetscCall(MatDestroy(&A3));
154:   PetscCall(MatDestroy(&A4));
155:   PetscCall(PetscFinalize());
156:   return 0;
157: }

159: /*TEST

161:    test:
162:       diff_args: -j
163:       nsize: 2
164:       suffix: 1

166:    test:
167:       diff_args: -j
168:       nsize: 2
169:       suffix: 1_null
170:       args: -test_null

172:    test:
173:       diff_args: -j
174:       suffix: 2

176:    test:
177:       diff_args: -j
178:       suffix: 2_null
179:       args: -test_null

181: TEST*/