Actual source code: ex2.c
slepc-3.18.3 2023-03-24
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[] = "Standard symmetric eigenproblem corresponding to the Laplacian operator in 2 dimensions.\n\n"
12: "The command line options are:\n"
13: " -n <n>, where <n> = number of grid subdivisions in x dimension.\n"
14: " -m <m>, where <m> = number of grid subdivisions in y dimension.\n\n";
16: #include <slepceps.h>
18: int main(int argc,char **argv)
19: {
20: Mat A; /* operator matrix */
21: EPS eps; /* eigenproblem solver context */
22: EPSType type;
23: PetscInt N,n=10,m,Istart,Iend,II,nev,i,j;
24: PetscBool flag,terse;
27: SlepcInitialize(&argc,&argv,(char*)0,help);
29: PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL);
30: PetscOptionsGetInt(NULL,NULL,"-m",&m,&flag);
31: if (!flag) m=n;
32: N = n*m;
33: PetscPrintf(PETSC_COMM_WORLD,"\n2-D Laplacian Eigenproblem, N=%" PetscInt_FMT " (%" PetscInt_FMT "x%" PetscInt_FMT " grid)\n\n",N,n,m);
35: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
36: Compute the operator matrix that defines the eigensystem, Ax=kx
37: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
39: MatCreate(PETSC_COMM_WORLD,&A);
40: MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,N,N);
41: MatSetFromOptions(A);
42: MatSetUp(A);
44: MatGetOwnershipRange(A,&Istart,&Iend);
45: for (II=Istart;II<Iend;II++) {
46: i = II/n; j = II-i*n;
47: if (i>0) MatSetValue(A,II,II-n,-1.0,INSERT_VALUES);
48: if (i<m-1) MatSetValue(A,II,II+n,-1.0,INSERT_VALUES);
49: if (j>0) MatSetValue(A,II,II-1,-1.0,INSERT_VALUES);
50: if (j<n-1) MatSetValue(A,II,II+1,-1.0,INSERT_VALUES);
51: MatSetValue(A,II,II,4.0,INSERT_VALUES);
52: }
54: MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
55: MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
57: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
58: Create the eigensolver and set various options
59: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
61: /*
62: Create eigensolver context
63: */
64: EPSCreate(PETSC_COMM_WORLD,&eps);
66: /*
67: Set operators. In this case, it is a standard eigenvalue problem
68: */
69: EPSSetOperators(eps,A,NULL);
70: EPSSetProblemType(eps,EPS_HEP);
72: /*
73: Set solver parameters at runtime
74: */
75: EPSSetFromOptions(eps);
77: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
78: Solve the eigensystem
79: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
81: EPSSolve(eps);
83: /*
84: Optional: Get some information from the solver and display it
85: */
86: EPSGetType(eps,&type);
87: PetscPrintf(PETSC_COMM_WORLD," Solution method: %s\n\n",type);
88: EPSGetDimensions(eps,&nev,NULL,NULL);
89: PetscPrintf(PETSC_COMM_WORLD," Number of requested eigenvalues: %" PetscInt_FMT "\n",nev);
91: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
92: Display solution and clean up
93: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
95: /* show detailed info unless -terse option is given by user */
96: PetscOptionsHasName(NULL,NULL,"-terse",&terse);
97: if (terse) EPSErrorView(eps,EPS_ERROR_RELATIVE,NULL);
98: else {
99: PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD,PETSC_VIEWER_ASCII_INFO_DETAIL);
100: EPSConvergedReasonView(eps,PETSC_VIEWER_STDOUT_WORLD);
101: EPSErrorView(eps,EPS_ERROR_RELATIVE,PETSC_VIEWER_STDOUT_WORLD);
102: PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD);
103: }
104: EPSDestroy(&eps);
105: MatDestroy(&A);
106: SlepcFinalize();
107: return 0;
108: }
110: /*TEST
112: testset:
113: args: -n 72 -eps_nev 4 -eps_ncv 20 -terse
114: output_file: output/ex2_1.out
115: requires: !single
116: test:
117: suffix: 1
118: test:
119: suffix: 2
120: args: -library_preload
122: testset:
123: args: -n 30 -eps_type ciss -eps_ciss_realmats -terse
124: requires: !single
125: output_file: output/ex2_ciss.out
126: filter: grep -v method
127: test:
128: suffix: ciss_1
129: nsize: 1
130: args: -rg_type interval -rg_interval_endpoints 1.1,1.25,-.1,.1
131: requires: complex
132: test:
133: suffix: ciss_1_hpddm
134: nsize: 1
135: args: -rg_type interval -rg_interval_endpoints 1.1,1.25 -st_ksp_type hpddm
136: requires: hpddm
137: test:
138: suffix: ciss_2
139: nsize: 2
140: args: -rg_type ellipse -rg_ellipse_center 1.175 -rg_ellipse_radius 0.075 -eps_ciss_partitions 2
141: test:
142: suffix: ciss_2_block
143: args: -rg_type ellipse -rg_ellipse_center 1.175 -rg_ellipse_radius 0.075 -eps_ciss_blocksize 3 -eps_ciss_moments 2
144: requires: complex !__float128
145: test:
146: suffix: ciss_2_hpddm
147: nsize: 2
148: args: -rg_type ellipse -rg_ellipse_center 1.175 -rg_ellipse_radius 0.075 -eps_ciss_partitions 2 -eps_ciss_ksp_type hpddm
149: requires: hpddm
150: test:
151: suffix: feast
152: args: -eps_type feast -eps_interval 1.1,1.25 -eps_ncv 64
153: requires: feast
155: testset:
156: args: -n 30 -m 30 -eps_interval 3.9,4.15 -terse
157: output_file: output/ex2_3.out
158: filter: grep -v Solution
159: requires: !single
160: test:
161: suffix: 3
162: args: -st_type sinvert -st_pc_type cholesky
163: test:
164: suffix: 3_evsl
165: args: -eps_type evsl -eps_evsl_slices 6
166: requires: evsl
168: testset:
169: args: -n 45 -m 46 -eps_interval 4.54,4.57 -eps_ncv 24 -terse
170: output_file: output/ex2_4.out
171: filter: grep -v Solution
172: requires: !single
173: timeoutfactor: 2
174: test:
175: suffix: 4
176: args: -st_type sinvert -st_pc_type cholesky
177: test:
178: suffix: 4_filter
179: args: -eps_type {{krylovschur subspace}} -st_type filter -st_filter_degree 200
180: requires: !__float128
181: test:
182: suffix: 4_filter_cuda
183: args: -eps_type {{krylovschur subspace}} -st_type filter -st_filter_degree 200 -mat_type aijcusparse
184: requires: cuda
185: test:
186: suffix: 4_evsl
187: args: -eps_type evsl
188: requires: evsl
190: TEST*/