Actual source code: test3.c
slepc-3.17.0 2022-03-31
1: /*
2: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
3: SLEPc - Scalable Library for Eigenvalue Problem Computations
4: Copyright (c) 2002-, Universitat Politecnica de Valencia, Spain
6: This file is part of SLEPc.
7: SLEPc is distributed under a 2-clause BSD license (see LICENSE).
8: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
9: */
11: static char help[] = "Test MFN interface functions.\n\n"
12: "The command line options are:\n"
13: " -n <n>, where <n> = number of grid subdivisions in x dimension.\n\n";
15: #include <slepcmfn.h>
17: int main(int argc,char **argv)
18: {
19: Mat A,B;
20: MFN mfn;
21: FN f;
22: MFNConvergedReason reason;
23: MFNType type;
24: PetscReal norm,tol;
25: Vec v,y;
26: PetscInt N,n=4,Istart,Iend,i,j,II,ncv,its,maxit;
27: PetscBool flg,testprefix=PETSC_FALSE;
28: const char *prefix;
29: PetscViewerAndFormat *vf;
31: SlepcInitialize(&argc,&argv,(char*)0,help);
32: PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL);
33: N = n*n;
34: PetscPrintf(PETSC_COMM_WORLD,"\nSquare root of Laplacian y=sqrt(A)*e_1, N=%" PetscInt_FMT " (%" PetscInt_FMT "x%" PetscInt_FMT " grid)\n\n",N,n,n);
35: PetscOptionsGetBool(NULL,NULL,"-test_prefix",&testprefix,NULL);
37: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
38: Compute the discrete 2-D Laplacian, A
39: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
41: MatCreate(PETSC_COMM_WORLD,&A);
42: MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,N,N);
43: MatSetFromOptions(A);
44: MatSetUp(A);
46: MatGetOwnershipRange(A,&Istart,&Iend);
47: for (II=Istart;II<Iend;II++) {
48: i = II/n; j = II-i*n;
49: if (i>0) MatSetValue(A,II,II-n,-1.0,INSERT_VALUES);
50: if (i<n-1) MatSetValue(A,II,II+n,-1.0,INSERT_VALUES);
51: if (j>0) MatSetValue(A,II,II-1,-1.0,INSERT_VALUES);
52: if (j<n-1) MatSetValue(A,II,II+1,-1.0,INSERT_VALUES);
53: MatSetValue(A,II,II,4.0,INSERT_VALUES);
54: }
56: MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
57: MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
58: MatSetOption(A,MAT_HERMITIAN,PETSC_TRUE);
60: MatCreateVecs(A,NULL,&v);
61: VecSetValue(v,0,1.0,INSERT_VALUES);
62: VecAssemblyBegin(v);
63: VecAssemblyEnd(v);
64: VecDuplicate(v,&y);
66: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
67: Create the solver, set the matrix and the function
68: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
69: MFNCreate(PETSC_COMM_WORLD,&mfn);
70: MFNSetOperator(mfn,A);
71: MFNGetFN(mfn,&f);
72: FNSetType(f,FNSQRT);
74: MFNSetType(mfn,MFNKRYLOV);
75: MFNGetType(mfn,&type);
76: PetscPrintf(PETSC_COMM_WORLD," Type set to %s\n",type);
78: /* test prefix usage */
79: if (testprefix) {
80: MFNSetOptionsPrefix(mfn,"check_");
81: MFNAppendOptionsPrefix(mfn,"myprefix_");
82: MFNGetOptionsPrefix(mfn,&prefix);
83: PetscPrintf(PETSC_COMM_WORLD," MFN prefix is currently: %s\n",prefix);
84: }
86: /* test some interface functions */
87: MFNGetOperator(mfn,&B);
88: MatView(B,PETSC_VIEWER_STDOUT_WORLD);
89: MFNSetTolerances(mfn,1e-4,500);
90: MFNSetDimensions(mfn,6);
91: MFNSetErrorIfNotConverged(mfn,PETSC_TRUE);
92: /* test monitors */
93: PetscViewerAndFormatCreate(PETSC_VIEWER_STDOUT_WORLD,PETSC_VIEWER_DEFAULT,&vf);
94: MFNMonitorSet(mfn,(PetscErrorCode (*)(MFN,PetscInt,PetscReal,void*))MFNMonitorDefault,vf,(PetscErrorCode (*)(void**))PetscViewerAndFormatDestroy);
95: /* MFNMonitorCancel(mfn); */
96: MFNSetFromOptions(mfn);
98: /* query properties and print them */
99: MFNGetTolerances(mfn,&tol,&maxit);
100: PetscPrintf(PETSC_COMM_WORLD," Tolerance: %g, max iterations: %" PetscInt_FMT "\n",(double)tol,maxit);
101: MFNGetDimensions(mfn,&ncv);
102: PetscPrintf(PETSC_COMM_WORLD," Subspace dimension: %" PetscInt_FMT "\n",ncv);
103: MFNGetErrorIfNotConverged(mfn,&flg);
104: if (flg) PetscPrintf(PETSC_COMM_WORLD," Erroring out if convergence fails\n");
106: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
107: Solve y=sqrt(A)*v
108: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
110: MFNSolve(mfn,v,y);
111: MFNGetConvergedReason(mfn,&reason);
112: MFNGetIterationNumber(mfn,&its);
113: PetscPrintf(PETSC_COMM_WORLD," Finished - converged reason = %d\n",(int)reason);
114: /* PetscPrintf(PETSC_COMM_WORLD," its = %" PetscInt_FMT "\n",its); */
115: VecNorm(y,NORM_2,&norm);
116: PetscPrintf(PETSC_COMM_WORLD," sqrt(A)*v has norm %g\n",(double)norm);
118: /*
119: Free work space
120: */
121: MFNDestroy(&mfn);
122: MatDestroy(&A);
123: VecDestroy(&v);
124: VecDestroy(&y);
125: SlepcFinalize();
126: return 0;
127: }
129: /*TEST
131: test:
132: suffix: 1
133: args: -mfn_monitor_cancel -mfn_converged_reason -mfn_view -log_exclude mfn,bv,fn -mfn_monitor draw::draw_lg -draw_virtual
135: test:
136: suffix: 2
137: args: -test_prefix -check_myprefix_mfn_monitor
138: filter: sed -e "s/estimate [0-9]\.[0-9]*e[+-]\([0-9]*\)/estimate (removed)/g" | sed -e "s/4.0[0-9]*e-10/4.03e-10/"
140: TEST*/