Actual source code: test2.c
slepc-3.19.2 2023-09-05
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 ST with one matrix.\n\n";
13: #include <slepcst.h>
15: int main(int argc,char **argv)
16: {
17: Mat A,B,mat[1];
18: ST st;
19: Vec v,w;
20: STType type;
21: PetscScalar sigma,tau;
22: PetscInt n=10,i,Istart,Iend;
24: PetscFunctionBeginUser;
25: PetscCall(SlepcInitialize(&argc,&argv,(char*)0,help));
26: PetscCall(PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL));
27: PetscCall(PetscPrintf(PETSC_COMM_WORLD,"\n1-D Laplacian, n=%" PetscInt_FMT "\n\n",n));
29: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
30: Compute the operator matrix for the 1-D Laplacian
31: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
33: PetscCall(MatCreate(PETSC_COMM_WORLD,&A));
34: PetscCall(MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,n,n));
35: PetscCall(MatSetFromOptions(A));
36: PetscCall(MatSetUp(A));
38: PetscCall(MatGetOwnershipRange(A,&Istart,&Iend));
39: for (i=Istart;i<Iend;i++) {
40: if (i>0) PetscCall(MatSetValue(A,i,i-1,-1.0,INSERT_VALUES));
41: if (i<n-1) PetscCall(MatSetValue(A,i,i+1,-1.0,INSERT_VALUES));
42: PetscCall(MatSetValue(A,i,i,2.0,INSERT_VALUES));
43: }
44: PetscCall(MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY));
45: PetscCall(MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY));
46: PetscCall(MatCreateVecs(A,&v,&w));
47: PetscCall(VecSet(v,1.0));
49: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
50: Create the spectral transformation object
51: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
53: PetscCall(STCreate(PETSC_COMM_WORLD,&st));
54: mat[0] = A;
55: PetscCall(STSetMatrices(st,1,mat));
56: PetscCall(STSetTransform(st,PETSC_TRUE));
57: PetscCall(STSetFromOptions(st));
59: /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
60: Apply the transformed operator for several ST's
61: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
63: /* shift, sigma=0.0 */
64: PetscCall(STSetUp(st));
65: PetscCall(STGetType(st,&type));
66: PetscCall(PetscPrintf(PETSC_COMM_WORLD,"ST type %s\n",type));
67: PetscCall(STApply(st,v,w));
68: PetscCall(VecView(w,NULL));
70: /* shift, sigma=0.1 */
71: sigma = 0.1;
72: PetscCall(STSetShift(st,sigma));
73: PetscCall(STGetShift(st,&sigma));
74: PetscCall(PetscPrintf(PETSC_COMM_WORLD,"With shift=%g\n",(double)PetscRealPart(sigma)));
75: PetscCall(STApply(st,v,w));
76: PetscCall(VecView(w,NULL));
77: PetscCall(STApplyTranspose(st,v,w));
78: PetscCall(VecView(w,NULL));
80: /* sinvert, sigma=0.1 */
81: PetscCall(STPostSolve(st)); /* undo changes if inplace */
82: PetscCall(STSetType(st,STSINVERT));
83: PetscCall(STGetType(st,&type));
84: PetscCall(PetscPrintf(PETSC_COMM_WORLD,"ST type %s\n",type));
85: PetscCall(STGetShift(st,&sigma));
86: PetscCall(PetscPrintf(PETSC_COMM_WORLD,"With shift=%g\n",(double)PetscRealPart(sigma)));
87: PetscCall(STApply(st,v,w));
88: PetscCall(VecView(w,NULL));
90: /* sinvert, sigma=-0.5 */
91: sigma = -0.5;
92: PetscCall(STSetShift(st,sigma));
93: PetscCall(STGetShift(st,&sigma));
94: PetscCall(PetscPrintf(PETSC_COMM_WORLD,"With shift=%g\n",(double)PetscRealPart(sigma)));
95: PetscCall(STApply(st,v,w));
96: PetscCall(VecView(w,NULL));
98: /* cayley, sigma=-0.5, tau=-0.5 (equal to sigma by default) */
99: PetscCall(STPostSolve(st)); /* undo changes if inplace */
100: PetscCall(STSetType(st,STCAYLEY));
101: PetscCall(STSetUp(st));
102: PetscCall(STGetType(st,&type));
103: PetscCall(PetscPrintf(PETSC_COMM_WORLD,"ST type %s\n",type));
104: PetscCall(STGetShift(st,&sigma));
105: PetscCall(STCayleyGetAntishift(st,&tau));
106: PetscCall(PetscPrintf(PETSC_COMM_WORLD,"With shift=%g, antishift=%g\n",(double)PetscRealPart(sigma),(double)PetscRealPart(tau)));
107: PetscCall(STApply(st,v,w));
108: PetscCall(VecView(w,NULL));
110: /* cayley, sigma=1.1, tau=1.1 (still equal to sigma) */
111: sigma = 1.1;
112: PetscCall(STSetShift(st,sigma));
113: PetscCall(STGetShift(st,&sigma));
114: PetscCall(STCayleyGetAntishift(st,&tau));
115: PetscCall(PetscPrintf(PETSC_COMM_WORLD,"With shift=%g, antishift=%g\n",(double)PetscRealPart(sigma),(double)PetscRealPart(tau)));
116: PetscCall(STApply(st,v,w));
117: PetscCall(VecView(w,NULL));
119: /* cayley, sigma=1.1, tau=-1.0 */
120: tau = -1.0;
121: PetscCall(STCayleySetAntishift(st,tau));
122: PetscCall(STGetShift(st,&sigma));
123: PetscCall(STCayleyGetAntishift(st,&tau));
124: PetscCall(PetscPrintf(PETSC_COMM_WORLD,"With shift=%g, antishift=%g\n",(double)PetscRealPart(sigma),(double)PetscRealPart(tau)));
125: PetscCall(STApply(st,v,w));
126: PetscCall(VecView(w,NULL));
128: /* check inner product matrix in Cayley */
129: PetscCall(STGetBilinearForm(st,&B));
130: PetscCall(MatMult(B,v,w));
131: PetscCall(VecView(w,NULL));
133: /* check again sinvert, sigma=0.1 */
134: PetscCall(STPostSolve(st)); /* undo changes if inplace */
135: PetscCall(STSetType(st,STSINVERT));
136: PetscCall(STGetType(st,&type));
137: PetscCall(PetscPrintf(PETSC_COMM_WORLD,"ST type %s\n",type));
138: sigma = 0.1;
139: PetscCall(STSetShift(st,sigma));
140: PetscCall(STGetShift(st,&sigma));
141: PetscCall(PetscPrintf(PETSC_COMM_WORLD,"With shift=%g\n",(double)PetscRealPart(sigma)));
142: PetscCall(STApply(st,v,w));
143: PetscCall(VecView(w,NULL));
145: PetscCall(STDestroy(&st));
146: PetscCall(MatDestroy(&A));
147: PetscCall(MatDestroy(&B));
148: PetscCall(VecDestroy(&v));
149: PetscCall(VecDestroy(&w));
150: PetscCall(SlepcFinalize());
151: return 0;
152: }
154: /*TEST
156: test:
157: suffix: 1
158: args: -st_matmode {{copy inplace shell}}
159: output_file: output/test2_1.out
160: requires: !single
162: TEST*/