xref: /petsc/src/mat/tests/ex78.c (revision 8dbb0df66754dee4fb72dff2ad56e76db1e6b7c7)
1 
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";
9 
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
22 
23 rhs
24 ---
25 0 3.0
26 1 12.0
27 2 6.0
28 
29 solu
30 ----
31 0 1.0
32 0 1.0
33 0 1.0
34 */
35 
36 #include <petscmat.h>
37 
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   PetscErrorCode ierr;
44   int            m,n = 0,nz,dummy; /* these are fscaned so kept as int */
45   PetscInt       i,col,row,shift = 1,sizes[3],nsizes;
46   PetscScalar    val;
47   PetscReal      res_norm;
48   FILE           *Afile,*bfile,*ufile;
49   PetscViewer    view;
50   PetscBool      flg_A,flg_b,flg_u,flg;
51   PetscMPIInt    size;
52 
53   ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr;
54   ierr = MPI_Comm_size(PETSC_COMM_WORLD,&size);CHKERRMPI(ierr);
55   if (size != 1) SETERRQ(PETSC_COMM_WORLD,PETSC_ERR_SUP,"This is a uniprocessor example only!");
56 
57   /* Read in matrix, rhs and exact solution from ascii files */
58   ierr = PetscOptionsGetString(NULL,NULL,"-Ain",Ain,sizeof(Ain),&flg_A);CHKERRQ(ierr);
59   ierr = PetscOptionsHasName(NULL,NULL,"-noshift",&flg);CHKERRQ(ierr);
60   if (flg) shift = 0;
61   if (flg_A) {
62     ierr   = PetscPrintf(PETSC_COMM_SELF,"\n Read matrix in ascii format ...\n");CHKERRQ(ierr);
63     ierr   = PetscFOpen(PETSC_COMM_SELF,Ain,"r",&Afile);CHKERRQ(ierr);
64     nsizes = 3;
65     ierr   = PetscOptionsGetIntArray(NULL,NULL,"-nosizesinfile",sizes,&nsizes,&flg);CHKERRQ(ierr);
66     if (flg) {
67       if (nsizes != 3) SETERRQ(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       if (fscanf(Afile,"%d %d %d\n",&m,&n,&nz) != 3)  SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED,"Badly formatted input file\n");
73     }
74     ierr = PetscPrintf(PETSC_COMM_SELF,"m: %d, n: %d, nz: %d \n", m,n,nz);CHKERRQ(ierr);
75     if (m != n) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_ARG_SIZ, "Number of rows, cols must be same for this example\n");
76     ierr = MatCreate(PETSC_COMM_SELF,&A);CHKERRQ(ierr);
77     ierr = MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,m,n);CHKERRQ(ierr);
78     ierr = MatSetFromOptions(A);CHKERRQ(ierr);
79     ierr = MatSeqAIJSetPreallocation(A,nz/m,NULL);CHKERRQ(ierr);
80     ierr = MatSetOption(A,MAT_NEW_NONZERO_ALLOCATION_ERR,PETSC_FALSE);CHKERRQ(ierr);
81 
82     for (i=0; i<nz; i++) {
83       if (fscanf(Afile,"%d %d %le\n",&row,&col,(double*)&val) != 3) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED,"Badly formatted input file\n");
84       row -= shift; col -= shift;  /* set index set starts at 0 */
85       ierr = MatSetValues(A,1,&row,1,&col,&val,INSERT_VALUES);CHKERRQ(ierr);
86     }
87     ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
88     ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
89     fclose(Afile);
90   }
91 
92   ierr = PetscOptionsGetString(NULL,NULL,"-rhs",rhs,sizeof(rhs),&flg_b);CHKERRQ(ierr);
93   if (flg_b) {
94     ierr = VecCreate(PETSC_COMM_SELF,&b);CHKERRQ(ierr);
95     ierr = VecSetSizes(b,PETSC_DECIDE,n);CHKERRQ(ierr);
96     ierr = VecSetFromOptions(b);CHKERRQ(ierr);
97     ierr = PetscPrintf(PETSC_COMM_SELF,"\n Read rhs in ascii format ...\n");CHKERRQ(ierr);
98     ierr = PetscFOpen(PETSC_COMM_SELF,rhs,"r",&bfile);CHKERRQ(ierr);
99     for (i=0; i<n; i++) {
100       if (fscanf(bfile,"%d %le\n",&dummy,(double*)&val) != 2) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED,"Badly formatted input file\n");
101       ierr = VecSetValues(b,1,&i,&val,INSERT_VALUES);CHKERRQ(ierr);
102     }
103     ierr = VecAssemblyBegin(b);CHKERRQ(ierr);
104     ierr = VecAssemblyEnd(b);CHKERRQ(ierr);
105     fclose(bfile);
106   }
107 
108   ierr = PetscOptionsGetString(NULL,NULL,"-solu",solu,sizeof(solu),&flg_u);CHKERRQ(ierr);
109   if (flg_u) {
110     ierr = VecCreate(PETSC_COMM_SELF,&u);CHKERRQ(ierr);
111     ierr = VecSetSizes(u,PETSC_DECIDE,n);CHKERRQ(ierr);
112     ierr = VecSetFromOptions(u);CHKERRQ(ierr);
113     ierr = PetscPrintf(PETSC_COMM_SELF,"\n Read exact solution in ascii format ...\n");CHKERRQ(ierr);
114     ierr = PetscFOpen(PETSC_COMM_SELF,solu,"r",&ufile);CHKERRQ(ierr);
115     for (i=0; i<n; i++) {
116       if (fscanf(ufile,"%d  %le\n",&dummy,(double*)&val) != 2) SETERRQ(PETSC_COMM_SELF,PETSC_ERR_FILE_UNEXPECTED,"Badly formatted input file\n");
117       ierr = VecSetValues(u,1,&i,&val,INSERT_VALUES);CHKERRQ(ierr);
118     }
119     ierr = VecAssemblyBegin(u);CHKERRQ(ierr);
120     ierr = VecAssemblyEnd(u);CHKERRQ(ierr);
121     fclose(ufile);
122   }
123 
124   /* Write matrix, rhs and exact solution in Petsc binary file */
125   ierr = PetscPrintf(PETSC_COMM_SELF,"\n Write matrix in binary to 'matrix.dat' ...\n");CHKERRQ(ierr);
126   ierr = PetscViewerBinaryOpen(PETSC_COMM_SELF,"matrix.dat",FILE_MODE_WRITE,&view);CHKERRQ(ierr);
127   ierr = MatView(A,view);CHKERRQ(ierr);
128 
129   if (flg_b) { /* Write rhs in Petsc binary file */
130     ierr = PetscPrintf(PETSC_COMM_SELF,"\n Write rhs in binary to 'matrix.dat' ...\n");CHKERRQ(ierr);
131     ierr = VecView(b,view);CHKERRQ(ierr);
132   }
133   if (flg_u) {
134     ierr = PetscPrintf(PETSC_COMM_SELF,"\n Write exact solution in binary to 'matrix.dat' ...\n");CHKERRQ(ierr);
135     ierr = VecView(u,view);CHKERRQ(ierr);
136   }
137 
138   /* Check accuracy of the data */
139   if (flg_A & flg_b & flg_u) {
140     ierr = VecDuplicate(u,&u_tmp);CHKERRQ(ierr);
141     ierr = MatMult(A,u,u_tmp);CHKERRQ(ierr);
142     ierr = VecAXPY(u_tmp,-1.0,b);CHKERRQ(ierr);
143     ierr = VecNorm(u_tmp,NORM_2,&res_norm);CHKERRQ(ierr);
144     ierr = PetscPrintf(PETSC_COMM_SELF,"\n Accuracy of the reading data: | b - A*u |_2 : %g \n",res_norm);CHKERRQ(ierr);
145     ierr = VecDestroy(&u_tmp);CHKERRQ(ierr);
146   }
147 
148   ierr = MatDestroy(&A);CHKERRQ(ierr);
149   if (flg_b) {ierr = VecDestroy(&b);CHKERRQ(ierr);}
150   if (flg_u) {ierr = VecDestroy(&u);CHKERRQ(ierr);}
151   ierr = PetscViewerDestroy(&view);CHKERRQ(ierr);
152   ierr = PetscFinalize();
153   return ierr;
154 }
155 
156 /*TEST
157 
158    build:
159       requires:  !defined(PETSC_USE_64BIT_INDICES) double !complex
160 
161    test:
162       requires: datafilespath
163       args: -Ain ${DATAFILESPATH}/matrices/indefinite/afiro_A.dat
164 
165 TEST*/
166