Actual source code: test2.c
slepc-3.23.0 2025-03-29
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 dense LME functions.\n\n";
13: #include <slepclme.h>
15: int main(int argc,char **argv)
16: {
17: LME lme;
18: Mat A,B,C,X;
19: PetscInt i,j,n=10,k=2;
20: PetscScalar *As,*Bs,*Cs,*Xs;
21: PetscViewer viewer;
22: PetscBool verbose;
24: PetscFunctionBeginUser;
25: PetscCall(SlepcInitialize(&argc,&argv,NULL,help));
26: PetscCall(PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL));
27: PetscCall(PetscOptionsGetInt(NULL,NULL,"-k",&k,NULL));
28: PetscCall(PetscOptionsHasName(NULL,NULL,"-verbose",&verbose));
29: PetscCall(PetscPrintf(PETSC_COMM_WORLD,"Dense matrix equations, n=%" PetscInt_FMT ".\n",n));
31: /* Create LME object */
32: PetscCall(LMECreate(PETSC_COMM_WORLD,&lme));
34: /* Set up viewer */
35: PetscCall(PetscViewerASCIIGetStdout(PETSC_COMM_WORLD,&viewer));
36: if (verbose) PetscCall(PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_MATLAB));
38: /* Create matrices */
39: PetscCall(MatCreateSeqDense(PETSC_COMM_SELF,n,n,NULL,&A));
40: PetscCall(PetscObjectSetName((PetscObject)A,"A"));
41: PetscCall(MatCreateSeqDense(PETSC_COMM_SELF,n,n,NULL,&B));
42: PetscCall(PetscObjectSetName((PetscObject)B,"B"));
43: PetscCall(MatCreateSeqDense(PETSC_COMM_SELF,n,k,NULL,&C));
44: PetscCall(PetscObjectSetName((PetscObject)C,"C"));
45: PetscCall(MatCreateSeqDense(PETSC_COMM_SELF,n,n,NULL,&X));
46: PetscCall(PetscObjectSetName((PetscObject)X,"X"));
48: /* Fill A with an upper Hessenberg Toeplitz matrix */
49: PetscCall(MatDenseGetArray(A,&As));
50: for (i=0;i<n;i++) As[i+i*n]=3.0-(PetscReal)n/2;
51: for (i=0;i<n-1;i++) As[i+1+i*n]=0.5;
52: for (j=1;j<3;j++) {
53: for (i=0;i<n-j;i++) As[i+(i+j)*n]=1.0;
54: }
55: PetscCall(MatDenseRestoreArray(A,&As));
57: if (verbose) {
58: PetscCall(PetscPrintf(PETSC_COMM_WORLD,"Matrix A - - - - - - - -\n"));
59: PetscCall(MatView(A,viewer));
60: }
62: /* Fill B with the 1-D Laplacian matrix */
63: PetscCall(MatDenseGetArray(B,&Bs));
64: for (i=0;i<n;i++) Bs[i+i*n]=2.0;
65: for (i=0;i<n-1;i++) { Bs[i+1+i*n]=-1; Bs[i+(i+1)*n]=-1; }
66: PetscCall(MatDenseRestoreArray(B,&Bs));
68: if (verbose) {
69: PetscCall(PetscPrintf(PETSC_COMM_WORLD,"Matrix B - - - - - - - -\n"));
70: PetscCall(MatView(B,viewer));
71: }
73: /* Solve Lyapunov equation A*X+X*A'= -B */
74: PetscCall(PetscPrintf(PETSC_COMM_WORLD,"Solving Lyapunov equation for B\n"));
75: PetscCall(MatDenseGetArray(A,&As));
76: PetscCall(MatDenseGetArray(B,&Bs));
77: PetscCall(MatDenseGetArray(X,&Xs));
78: PetscCall(LMEDenseLyapunov(lme,n,As,n,Bs,n,Xs,n));
79: PetscCall(MatDenseRestoreArray(A,&As));
80: PetscCall(MatDenseRestoreArray(B,&Bs));
81: PetscCall(MatDenseRestoreArray(X,&Xs));
82: if (verbose) {
83: PetscCall(PetscPrintf(PETSC_COMM_WORLD,"Solution X - - - - - - - -\n"));
84: PetscCall(MatView(X,viewer));
85: }
87: /* Fill C with a full-rank nx2 matrix */
88: PetscCall(MatDenseGetArray(C,&Cs));
89: for (i=0;i<k;i++) Cs[i+i*n] = (i%2)? -1.0: 1.0;
90: PetscCall(MatDenseRestoreArray(C,&Cs));
92: if (verbose) {
93: PetscCall(PetscPrintf(PETSC_COMM_WORLD,"Matrix C - - - - - - - -\n"));
94: PetscCall(MatView(C,viewer));
95: }
97: /* Solve Lyapunov equation A*X+X*A'= -C*C' */
98: PetscCall(PetscPrintf(PETSC_COMM_WORLD,"Solving Lyapunov equation for C (Cholesky)\n"));
99: PetscCall(MatDenseGetArray(A,&As));
100: PetscCall(MatDenseGetArray(C,&Cs));
101: PetscCall(MatDenseGetArray(X,&Xs));
102: PetscCall(LMEDenseHessLyapunovChol(lme,n,As,n,2,Cs,n,Xs,n,NULL));
103: PetscCall(MatDenseRestoreArray(A,&As));
104: PetscCall(MatDenseRestoreArray(C,&Cs));
105: PetscCall(MatDenseRestoreArray(X,&Xs));
106: if (verbose) {
107: PetscCall(PetscPrintf(PETSC_COMM_WORLD,"Solution X - - - - - - - -\n"));
108: PetscCall(MatView(X,viewer));
109: }
111: PetscCall(MatDestroy(&A));
112: PetscCall(MatDestroy(&B));
113: PetscCall(MatDestroy(&C));
114: PetscCall(MatDestroy(&X));
115: PetscCall(LMEDestroy(&lme));
116: PetscCall(SlepcFinalize());
117: return 0;
118: }
120: /*TEST
122: test:
123: args: -info :lme
124: requires: double
125: filter: sed -e "s/[0-9]\.[0-9]*e[+-]\([0-9]*\)/1e-\\1/g"
127: TEST*/