Actual source code: test2.c
slepc-3.7.2 2016-07-19
1: /*
2: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
3: SLEPc - Scalable Library for Eigenvalue Problem Computations
4: Copyright (c) 2002-2016, Universitat Politecnica de Valencia, Spain
6: This file is part of SLEPc.
8: SLEPc is free software: you can redistribute it and/or modify it under the
9: terms of version 3 of the GNU Lesser General Public License as published by
10: the Free Software Foundation.
12: SLEPc is distributed in the hope that it will be useful, but WITHOUT ANY
13: WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
14: FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for
15: more details.
17: You should have received a copy of the GNU Lesser General Public License
18: along with SLEPc. If not, see <http://www.gnu.org/licenses/>.
19: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
20: */
22: static char help[] = "Test ST with one matrix.\n\n";
24: #include <slepcst.h>
28: int main(int argc,char **argv)
29: {
30: Mat A,B,mat[1];
31: ST st;
32: Vec v,w;
33: STType type;
34: PetscScalar sigma,tau;
35: PetscInt n=10,i,Istart,Iend;
38: SlepcInitialize(&argc,&argv,(char*)0,help);
39: PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL);
40: PetscPrintf(PETSC_COMM_WORLD,"\n1-D Laplacian, n=%D\n\n",n);
42: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
43: Compute the operator matrix for the 1-D Laplacian
44: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
46: MatCreate(PETSC_COMM_WORLD,&A);
47: MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,n,n);
48: MatSetFromOptions(A);
49: MatSetUp(A);
51: MatGetOwnershipRange(A,&Istart,&Iend);
52: for (i=Istart;i<Iend;i++) {
53: if (i>0) { MatSetValue(A,i,i-1,-1.0,INSERT_VALUES); }
54: if (i<n-1) { MatSetValue(A,i,i+1,-1.0,INSERT_VALUES); }
55: MatSetValue(A,i,i,2.0,INSERT_VALUES);
56: }
57: MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
58: MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
59: MatCreateVecs(A,&v,&w);
60: VecSet(v,1.0);
62: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
63: Create the spectral transformation object
64: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
66: STCreate(PETSC_COMM_WORLD,&st);
67: mat[0] = A;
68: STSetOperators(st,1,mat);
69: STSetTransform(st,PETSC_TRUE);
70: STSetFromOptions(st);
72: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
73: Apply the transformed operator for several ST's
74: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
76: /* shift, sigma=0.0 */
77: STSetUp(st);
78: STGetType(st,&type);
79: PetscPrintf(PETSC_COMM_WORLD,"ST type %s\n",type);
80: STApply(st,v,w);
81: VecView(w,NULL);
83: /* shift, sigma=0.1 */
84: sigma = 0.1;
85: STSetShift(st,sigma);
86: STGetShift(st,&sigma);
87: PetscPrintf(PETSC_COMM_WORLD,"With shift=%g\n",(double)PetscRealPart(sigma));
88: STApply(st,v,w);
89: VecView(w,NULL);
91: /* sinvert, sigma=0.1 */
92: STPostSolve(st); /* undo changes if inplace */
93: STSetType(st,STSINVERT);
94: STGetType(st,&type);
95: PetscPrintf(PETSC_COMM_WORLD,"ST type %s\n",type);
96: STGetShift(st,&sigma);
97: PetscPrintf(PETSC_COMM_WORLD,"With shift=%g\n",(double)PetscRealPart(sigma));
98: STApply(st,v,w);
99: VecView(w,NULL);
101: /* sinvert, sigma=-0.5 */
102: sigma = -0.5;
103: STSetShift(st,sigma);
104: STGetShift(st,&sigma);
105: PetscPrintf(PETSC_COMM_WORLD,"With shift=%g\n",(double)PetscRealPart(sigma));
106: STApply(st,v,w);
107: VecView(w,NULL);
109: /* cayley, sigma=-0.5, tau=-0.5 (equal to sigma by default) */
110: STPostSolve(st); /* undo changes if inplace */
111: STSetType(st,STCAYLEY);
112: STSetUp(st);
113: STGetType(st,&type);
114: PetscPrintf(PETSC_COMM_WORLD,"ST type %s\n",type);
115: STGetShift(st,&sigma);
116: STCayleyGetAntishift(st,&tau);
117: PetscPrintf(PETSC_COMM_WORLD,"With shift=%g, antishift=%g\n",(double)PetscRealPart(sigma),(double)PetscRealPart(tau));
118: STApply(st,v,w);
119: VecView(w,NULL);
121: /* cayley, sigma=1.1, tau=1.1 (still equal to sigma) */
122: sigma = 1.1;
123: STSetShift(st,sigma);
124: STGetShift(st,&sigma);
125: STCayleyGetAntishift(st,&tau);
126: PetscPrintf(PETSC_COMM_WORLD,"With shift=%g, antishift=%g\n",(double)PetscRealPart(sigma),(double)PetscRealPart(tau));
127: STApply(st,v,w);
128: VecView(w,NULL);
130: /* cayley, sigma=1.1, tau=-1.0 */
131: tau = -1.0;
132: STCayleySetAntishift(st,tau);
133: STGetShift(st,&sigma);
134: STCayleyGetAntishift(st,&tau);
135: PetscPrintf(PETSC_COMM_WORLD,"With shift=%g, antishift=%g\n",(double)PetscRealPart(sigma),(double)PetscRealPart(tau));
136: STApply(st,v,w);
137: VecView(w,NULL);
139: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
140: Check inner product matrix in Cayley
141: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
142: STGetBilinearForm(st,&B);
143: MatMult(B,v,w);
144: VecView(w,NULL);
146: STDestroy(&st);
147: MatDestroy(&A);
148: MatDestroy(&B);
149: VecDestroy(&v);
150: VecDestroy(&w);
151: SlepcFinalize();
152: return ierr;
153: }