xref: /petsc/src/mat/tests/ex195.c (revision 28b400f66ebc7ae0049166a2294dfcd3df27e64b)
1 /*
2  * ex195.c
3  *
4  *  Created on: Aug 24, 2015
5  *      Author: Fande Kong <fdkong.jd@gmail.com>
6  */
7 
8 static char help[] = " Demonstrate the use of MatConvert_Nest_AIJ\n";
9 
10 #include <petscmat.h>
11 
12 int main(int argc,char **args)
13 {
14   Mat                 A1,A2,A3,A4,A5,B,C,C1,nest;
15   Mat                 mata[4];
16   Mat                 aij;
17   MPI_Comm            comm;
18   PetscInt            m,M,n,istart,iend,ii,i,J,j,K=10;
19   PetscScalar         v;
20   PetscMPIInt         size;
21   PetscErrorCode      ierr;
22   PetscBool           equal;
23 
24   ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr;
25   comm = PETSC_COMM_WORLD;
26   CHKERRMPI(MPI_Comm_size(comm,&size));
27 
28   /*
29      Assemble the matrix for the five point stencil, YET AGAIN
30   */
31   CHKERRQ(MatCreate(comm,&A1));
32   m=2,n=2;
33   CHKERRQ(MatSetSizes(A1,PETSC_DECIDE,PETSC_DECIDE,m*n,m*n));
34   CHKERRQ(MatSetFromOptions(A1));
35   CHKERRQ(MatSetUp(A1));
36   CHKERRQ(MatGetOwnershipRange(A1,&istart,&iend));
37   for (ii=istart; ii<iend; ii++) {
38     v = -1.0; i = ii/n; j = ii - i*n;
39     if (i>0)   {J = ii - n; CHKERRQ(MatSetValues(A1,1,&ii,1,&J,&v,INSERT_VALUES));}
40     if (i<m-1) {J = ii + n; CHKERRQ(MatSetValues(A1,1,&ii,1,&J,&v,INSERT_VALUES));}
41     if (j>0)   {J = ii - 1; CHKERRQ(MatSetValues(A1,1,&ii,1,&J,&v,INSERT_VALUES));}
42     if (j<n-1) {J = ii + 1; CHKERRQ(MatSetValues(A1,1,&ii,1,&J,&v,INSERT_VALUES));}
43     v = 4.0; CHKERRQ(MatSetValues(A1,1,&ii,1,&ii,&v,INSERT_VALUES));
44   }
45   CHKERRQ(MatAssemblyBegin(A1,MAT_FINAL_ASSEMBLY));
46   CHKERRQ(MatAssemblyEnd(A1,MAT_FINAL_ASSEMBLY));
47   CHKERRQ(MatView(A1,PETSC_VIEWER_STDOUT_WORLD));
48 
49   CHKERRQ(MatDuplicate(A1,MAT_COPY_VALUES,&A2));
50   CHKERRQ(MatDuplicate(A1,MAT_COPY_VALUES,&A3));
51   CHKERRQ(MatDuplicate(A1,MAT_COPY_VALUES,&A4));
52 
53   /*create a nest matrix */
54   CHKERRQ(MatCreate(comm,&nest));
55   CHKERRQ(MatSetType(nest,MATNEST));
56   mata[0]=A1,mata[1]=A2,mata[2]=A3,mata[3]=A4;
57   CHKERRQ(MatNestSetSubMats(nest,2,NULL,2,NULL,mata));
58   CHKERRQ(MatSetUp(nest));
59   CHKERRQ(MatConvert(nest,MATAIJ,MAT_INITIAL_MATRIX,&aij));
60   CHKERRQ(MatView(aij,PETSC_VIEWER_STDOUT_WORLD));
61 
62   /* create a dense matrix */
63   CHKERRQ(MatGetSize(nest,&M,NULL));
64   CHKERRQ(MatGetLocalSize(nest,&m,NULL));
65   CHKERRQ(MatCreateDense(comm,m,PETSC_DECIDE,M,K,NULL,&B));
66   CHKERRQ(MatSetRandom(B,PETSC_NULL));
67   CHKERRQ(MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY));
68   CHKERRQ(MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY));
69 
70   /* C = nest*B_dense */
71   CHKERRQ(MatMatMult(nest,B,MAT_INITIAL_MATRIX,PETSC_DEFAULT,&C));
72   CHKERRQ(MatMatMult(nest,B,MAT_REUSE_MATRIX,PETSC_DEFAULT,&C));
73   CHKERRQ(MatMatMultEqual(nest,B,C,10,&equal));
74   PetscCheck(equal,PETSC_COMM_WORLD,PETSC_ERR_PLIB,"Error in C != nest*B_dense");
75 
76   /* Test B = nest*C, reuse C and B with MatProductCreateWithMat() */
77   /* C has been obtained from nest*B. Clear internal data structures related to factors to prevent circular references */
78   CHKERRQ(MatProductClear(C));
79   CHKERRQ(MatProductCreateWithMat(nest,C,NULL,B));
80   CHKERRQ(MatProductSetType(B,MATPRODUCT_AB));
81   CHKERRQ(MatProductSetFromOptions(B));
82   CHKERRQ(MatProductSymbolic(B));
83   CHKERRQ(MatProductNumeric(B));
84   CHKERRQ(MatMatMultEqual(nest,C,B,10,&equal));
85   PetscCheck(equal,PETSC_COMM_WORLD,PETSC_ERR_PLIB,"Error in B != nest*C_dense");
86   CHKERRQ(MatConvert(nest,MATAIJ,MAT_INPLACE_MATRIX,&nest));
87   CHKERRQ(MatEqual(nest,aij,&equal));
88   PetscCheck(equal,PETSC_COMM_WORLD,PETSC_ERR_PLIB,"Error in aij != nest");
89   CHKERRQ(MatDestroy(&nest));
90 
91   if (size > 1) { /* Do not know why this test fails for size = 1 */
92     CHKERRQ(MatCreateTranspose(A1,&A5)); /* A1 is symmetric */
93     mata[0] = A5;
94     CHKERRQ(MatCreate(comm,&nest));
95     CHKERRQ(MatSetType(nest,MATNEST));
96     CHKERRQ(MatNestSetSubMats(nest,2,NULL,2,NULL,mata));
97     CHKERRQ(MatSetUp(nest));
98     CHKERRQ(MatMatMult(nest,B,MAT_INITIAL_MATRIX,PETSC_DEFAULT,&C1));
99     CHKERRQ(MatMatMult(nest,B,MAT_REUSE_MATRIX,PETSC_DEFAULT,&C1));
100 
101     CHKERRQ(MatMatMultEqual(nest,B,C1,10,&equal));
102     PetscCheck(equal,PETSC_COMM_WORLD,PETSC_ERR_PLIB,"Error in C1 != C");
103     CHKERRQ(MatDestroy(&C1));
104     CHKERRQ(MatDestroy(&A5));
105     CHKERRQ(MatDestroy(&nest));
106   }
107 
108   CHKERRQ(MatDestroy(&C));
109   CHKERRQ(MatDestroy(&B));
110   CHKERRQ(MatDestroy(&aij));
111   CHKERRQ(MatDestroy(&A1));
112   CHKERRQ(MatDestroy(&A2));
113   CHKERRQ(MatDestroy(&A3));
114   CHKERRQ(MatDestroy(&A4));
115   ierr = PetscFinalize();
116   return ierr;
117 }
118 
119 /*TEST
120 
121    test:
122       nsize: 2
123 
124    test:
125       suffix: 2
126 
127 TEST*/
128