Actual source code: test1.c

slepc-3.22.1 2024-10-28
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  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 shell matrices.\n\n";

 13: #include <slepcst.h>

 15: static PetscErrorCode MatMult_Shell(Mat S,Vec x,Vec y);
 16: static PetscErrorCode MatMultTranspose_Shell(Mat S,Vec x,Vec y);
 17: #if defined(PETSC_USE_COMPLEX)
 18: static PetscErrorCode MatMultHermitianTranspose_Shell(Mat S,Vec x,Vec y);
 19: #endif
 20: static PetscErrorCode MatGetDiagonal_Shell(Mat S,Vec diag);
 21: static PetscErrorCode MatDuplicate_Shell(Mat S,MatDuplicateOption op,Mat *M);

 23: static PetscErrorCode MyShellMatCreate(Mat *A,Mat *M)
 24: {
 25:   MPI_Comm       comm;
 26:   PetscInt       n;

 28:   PetscFunctionBeginUser;
 29:   PetscCall(MatGetSize(*A,&n,NULL));
 30:   PetscCall(PetscObjectGetComm((PetscObject)*A,&comm));
 31:   PetscCall(MatCreateShell(comm,PETSC_DECIDE,PETSC_DECIDE,n,n,A,M));
 32:   PetscCall(MatShellSetOperation(*M,MATOP_MULT,(void(*)(void))MatMult_Shell));
 33:   PetscCall(MatShellSetOperation(*M,MATOP_MULT_TRANSPOSE,(void(*)(void))MatMultTranspose_Shell));
 34: #if defined(PETSC_USE_COMPLEX)
 35:   PetscCall(MatShellSetOperation(*M,MATOP_MULT_HERMITIAN_TRANSPOSE,(void(*)(void))MatMultHermitianTranspose_Shell));
 36: #endif
 37:   PetscCall(MatShellSetOperation(*M,MATOP_GET_DIAGONAL,(void(*)(void))MatGetDiagonal_Shell));
 38:   PetscCall(MatShellSetOperation(*M,MATOP_DUPLICATE,(void(*)(void))MatDuplicate_Shell));
 39:   PetscFunctionReturn(PETSC_SUCCESS);
 40: }

 42: int main(int argc,char **argv)
 43: {
 44:   Mat            A,S,mat[1];
 45:   ST             st;
 46:   Vec            v,w;
 47:   STType         type;
 48:   KSP            ksp;
 49:   PC             pc;
 50:   PetscScalar    sigma;
 51:   PetscInt       n=10,i,Istart,Iend;

 53:   PetscFunctionBeginUser;
 54:   PetscCall(SlepcInitialize(&argc,&argv,NULL,help));
 55:   PetscCall(PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL));
 56:   PetscCall(PetscPrintf(PETSC_COMM_WORLD,"\n1-D Laplacian with shell matrices, n=%" PetscInt_FMT "\n\n",n));

 58:   /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 59:      Compute the operator matrix for the 1-D Laplacian
 60:      - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

 62:   PetscCall(MatCreate(PETSC_COMM_WORLD,&A));
 63:   PetscCall(MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,n,n));
 64:   PetscCall(MatSetFromOptions(A));

 66:   PetscCall(MatGetOwnershipRange(A,&Istart,&Iend));
 67:   for (i=Istart;i<Iend;i++) {
 68:     if (i>0) PetscCall(MatSetValue(A,i,i-1,-1.0,INSERT_VALUES));
 69:     if (i<n-1) PetscCall(MatSetValue(A,i,i+1,-1.0,INSERT_VALUES));
 70:     PetscCall(MatSetValue(A,i,i,2.0,INSERT_VALUES));
 71:   }
 72:   PetscCall(MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY));
 73:   PetscCall(MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY));

 75:   /* create the shell version of A */
 76:   PetscCall(MyShellMatCreate(&A,&S));

 78:   /* work vectors */
 79:   PetscCall(MatCreateVecs(A,&v,&w));
 80:   PetscCall(VecSet(v,1.0));

 82:   /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 83:                 Create the spectral transformation object
 84:      - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

 86:   PetscCall(STCreate(PETSC_COMM_WORLD,&st));
 87:   mat[0] = S;
 88:   PetscCall(STSetMatrices(st,1,mat));
 89:   PetscCall(STSetTransform(st,PETSC_TRUE));
 90:   PetscCall(STSetFromOptions(st));

 92:   /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
 93:               Apply the transformed operator for several ST's
 94:      - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

 96:   /* shift, sigma=0.0 */
 97:   PetscCall(STSetUp(st));
 98:   PetscCall(STGetType(st,&type));
 99:   PetscCall(PetscPrintf(PETSC_COMM_WORLD,"ST type %s\n",type));
100:   PetscCall(STApply(st,v,w));
101:   PetscCall(VecView(w,NULL));
102:   PetscCall(STApplyHermitianTranspose(st,v,w));
103:   PetscCall(VecView(w,NULL));

105:   /* shift, sigma=0.1 */
106:   sigma = 0.1;
107:   PetscCall(STSetShift(st,sigma));
108:   PetscCall(STGetShift(st,&sigma));
109:   PetscCall(PetscPrintf(PETSC_COMM_WORLD,"With shift=%g\n",(double)PetscRealPart(sigma)));
110:   PetscCall(STApply(st,v,w));
111:   PetscCall(VecView(w,NULL));

113:   /* sinvert, sigma=0.1 */
114:   PetscCall(STPostSolve(st));   /* undo changes if inplace */
115:   PetscCall(STSetType(st,STSINVERT));
116:   PetscCall(STGetKSP(st,&ksp));
117:   PetscCall(KSPSetType(ksp,KSPGMRES));
118:   PetscCall(KSPGetPC(ksp,&pc));
119:   PetscCall(PCSetType(pc,PCJACOBI));
120:   PetscCall(STGetType(st,&type));
121:   PetscCall(PetscPrintf(PETSC_COMM_WORLD,"ST type %s\n",type));
122:   PetscCall(STGetShift(st,&sigma));
123:   PetscCall(PetscPrintf(PETSC_COMM_WORLD,"With shift=%g\n",(double)PetscRealPart(sigma)));
124:   PetscCall(STApply(st,v,w));
125:   PetscCall(VecView(w,NULL));

127:   /* sinvert, sigma=-0.5 */
128:   sigma = -0.5;
129:   PetscCall(STSetShift(st,sigma));
130:   PetscCall(STGetShift(st,&sigma));
131:   PetscCall(PetscPrintf(PETSC_COMM_WORLD,"With shift=%g\n",(double)PetscRealPart(sigma)));
132:   PetscCall(STApply(st,v,w));
133:   PetscCall(VecView(w,NULL));

135:   PetscCall(STDestroy(&st));
136:   PetscCall(MatDestroy(&A));
137:   PetscCall(MatDestroy(&S));
138:   PetscCall(VecDestroy(&v));
139:   PetscCall(VecDestroy(&w));
140:   PetscCall(SlepcFinalize());
141:   return 0;
142: }

144: static PetscErrorCode MatMult_Shell(Mat S,Vec x,Vec y)
145: {
146:   Mat               *A;

148:   PetscFunctionBeginUser;
149:   PetscCall(MatShellGetContext(S,&A));
150:   PetscCall(MatMult(*A,x,y));
151:   PetscFunctionReturn(PETSC_SUCCESS);
152: }

154: static PetscErrorCode MatMultTranspose_Shell(Mat S,Vec x,Vec y)
155: {
156:   Mat               *A;

158:   PetscFunctionBeginUser;
159:   PetscCall(MatShellGetContext(S,&A));
160:   PetscCall(MatMultTranspose(*A,x,y));
161:   PetscFunctionReturn(PETSC_SUCCESS);
162: }

164: #if defined(PETSC_USE_COMPLEX)
165: static PetscErrorCode MatMultHermitianTranspose_Shell(Mat S,Vec x,Vec y)
166: {
167:   Mat               *A;

169:   PetscFunctionBeginUser;
170:   PetscCall(MatShellGetContext(S,&A));
171:   PetscCall(MatMultHermitianTranspose(*A,x,y));
172:   PetscFunctionReturn(PETSC_SUCCESS);
173: }
174: #endif

176: static PetscErrorCode MatGetDiagonal_Shell(Mat S,Vec diag)
177: {
178:   Mat               *A;

180:   PetscFunctionBeginUser;
181:   PetscCall(MatShellGetContext(S,&A));
182:   PetscCall(MatGetDiagonal(*A,diag));
183:   PetscFunctionReturn(PETSC_SUCCESS);
184: }

186: static PetscErrorCode MatDuplicate_Shell(Mat S,MatDuplicateOption op,Mat *M)
187: {
188:   Mat            *A;

190:   PetscFunctionBeginUser;
191:   PetscCall(MatShellGetContext(S,&A));
192:   PetscCall(MyShellMatCreate(A,M));
193:   PetscFunctionReturn(PETSC_SUCCESS);
194: }

196: /*TEST

198:    test:
199:       suffix: 1
200:       args: -st_matmode {{inplace shell}}
201:       requires: !single

203: TEST*/