Date: 2024-12-02T08:58:33+00:00

Actual source code: test9.c
slepc-3.22.2 2024-12-02
Report Typos and Errors

      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 four matrices and split preconditioner.\n\n";

     13: #include <slepcst.h>

     15: int main(int argc,char **argv)
     16: {
     17:   Mat            A,B,C,D,Pa,Pb,Pc,Pd,Pmat,mat[4];
     18:   ST             st;
     19:   KSP            ksp;
     20:   PC             pc;
     21:   Vec            v,w;
     22:   STType         type;
     23:   PetscScalar    sigma;
     24:   PetscInt       n=10,i,Istart,Iend;

     26:   PetscFunctionBeginUser;
     27:   PetscCall(SlepcInitialize(&argc,&argv,NULL,help));
     28:   PetscCall(PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL));
     29:   PetscCall(PetscPrintf(PETSC_COMM_WORLD,"\nTest ST with four matrices, n=%" PetscInt_FMT "\n\n",n));
     30:   /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
     31:      Compute the operator matrices
     32:      - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

     34:   PetscCall(MatCreate(PETSC_COMM_WORLD,&A));
     35:   PetscCall(MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,n,n));
     36:   PetscCall(MatSetFromOptions(A));

     38:   PetscCall(MatCreate(PETSC_COMM_WORLD,&B));
     39:   PetscCall(MatSetSizes(B,PETSC_DECIDE,PETSC_DECIDE,n,n));
     40:   PetscCall(MatSetFromOptions(B));

     42:   PetscCall(MatCreate(PETSC_COMM_WORLD,&C));
     43:   PetscCall(MatSetSizes(C,PETSC_DECIDE,PETSC_DECIDE,n,n));
     44:   PetscCall(MatSetFromOptions(C));

     46:   PetscCall(MatCreate(PETSC_COMM_WORLD,&D));
     47:   PetscCall(MatSetSizes(D,PETSC_DECIDE,PETSC_DECIDE,n,n));
     48:   PetscCall(MatSetFromOptions(D));

     50:   PetscCall(MatGetOwnershipRange(A,&Istart,&Iend));
     51:   for (i=Istart;i<Iend;i++) {
     52:     PetscCall(MatSetValue(A,i,i,2.0,INSERT_VALUES));
     53:     if (i>0) {
     54:       PetscCall(MatSetValue(A,i,i-1,-1.0,INSERT_VALUES));
     55:       PetscCall(MatSetValue(B,i,i,(PetscScalar)i,INSERT_VALUES));
     56:     } else PetscCall(MatSetValue(B,i,i,-1.0,INSERT_VALUES));
     57:     if (i<n-1) PetscCall(MatSetValue(A,i,i+1,-1.0,INSERT_VALUES));
     58:     PetscCall(MatSetValue(C,i,n-i-1,1.0,INSERT_VALUES));
     59:     PetscCall(MatSetValue(D,i,i,i*.1,INSERT_VALUES));
     60:     if (i==0) PetscCall(MatSetValue(D,0,n-1,1.0,INSERT_VALUES));
     61:     if (i==n-1) PetscCall(MatSetValue(D,n-1,0,1.0,INSERT_VALUES));
     62:   }

     64:   PetscCall(MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY));
     65:   PetscCall(MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY));
     66:   PetscCall(MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY));
     67:   PetscCall(MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY));
     68:   PetscCall(MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY));
     69:   PetscCall(MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY));
     70:   PetscCall(MatAssemblyBegin(D,MAT_FINAL_ASSEMBLY));
     71:   PetscCall(MatAssemblyEnd(D,MAT_FINAL_ASSEMBLY));
     72:   PetscCall(MatCreateVecs(A,&v,&w));
     73:   PetscCall(VecSet(v,1.0));

     75:   /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
     76:      Compute the split preconditioner matrices (four diagonals)
     77:      - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

     79:   PetscCall(MatCreate(PETSC_COMM_WORLD,&Pa));
     80:   PetscCall(MatSetSizes(Pa,PETSC_DECIDE,PETSC_DECIDE,n,n));
     81:   PetscCall(MatSetFromOptions(Pa));

     83:   PetscCall(MatCreate(PETSC_COMM_WORLD,&Pb));
     84:   PetscCall(MatSetSizes(Pb,PETSC_DECIDE,PETSC_DECIDE,n,n));
     85:   PetscCall(MatSetFromOptions(Pb));

     87:   PetscCall(MatCreate(PETSC_COMM_WORLD,&Pc));
     88:   PetscCall(MatSetSizes(Pc,PETSC_DECIDE,PETSC_DECIDE,n,n));
     89:   PetscCall(MatSetFromOptions(Pc));

     91:   PetscCall(MatCreate(PETSC_COMM_WORLD,&Pd));
     92:   PetscCall(MatSetSizes(Pd,PETSC_DECIDE,PETSC_DECIDE,n,n));
     93:   PetscCall(MatSetFromOptions(Pd));

     95:   PetscCall(MatGetOwnershipRange(Pa,&Istart,&Iend));
     96:   for (i=Istart;i<Iend;i++) {
     97:     PetscCall(MatSetValue(Pa,i,i,2.0,INSERT_VALUES));
     98:     if (i>0) PetscCall(MatSetValue(Pb,i,i,(PetscScalar)i,INSERT_VALUES));
     99:     else PetscCall(MatSetValue(Pb,i,i,-1.0,INSERT_VALUES));
    100:     PetscCall(MatSetValue(Pd,i,i,i*.1,INSERT_VALUES));
    101:   }

    103:   PetscCall(MatAssemblyBegin(Pa,MAT_FINAL_ASSEMBLY));
    104:   PetscCall(MatAssemblyEnd(Pa,MAT_FINAL_ASSEMBLY));
    105:   PetscCall(MatAssemblyBegin(Pb,MAT_FINAL_ASSEMBLY));
    106:   PetscCall(MatAssemblyEnd(Pb,MAT_FINAL_ASSEMBLY));
    107:   PetscCall(MatAssemblyBegin(Pc,MAT_FINAL_ASSEMBLY));
    108:   PetscCall(MatAssemblyEnd(Pc,MAT_FINAL_ASSEMBLY));
    109:   PetscCall(MatAssemblyBegin(Pd,MAT_FINAL_ASSEMBLY));
    110:   PetscCall(MatAssemblyEnd(Pd,MAT_FINAL_ASSEMBLY));

    112:   /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
    113:                 Create the spectral transformation object
    114:      - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

    116:   PetscCall(STCreate(PETSC_COMM_WORLD,&st));
    117:   mat[0] = A;
    118:   mat[1] = B;
    119:   mat[2] = C;
    120:   mat[3] = D;
    121:   PetscCall(STSetMatrices(st,4,mat));
    122:   mat[0] = Pa;
    123:   mat[1] = Pb;
    124:   mat[2] = Pc;
    125:   mat[3] = Pd;
    126:   PetscCall(STSetSplitPreconditioner(st,4,mat,SUBSET_NONZERO_PATTERN));
    127:   PetscCall(STGetKSP(st,&ksp));
    128:   PetscCall(KSPSetTolerances(ksp,100*PETSC_MACHINE_EPSILON,PETSC_CURRENT,PETSC_CURRENT,PETSC_CURRENT));
    129:   PetscCall(STSetTransform(st,PETSC_TRUE));
    130:   PetscCall(STSetFromOptions(st));
    131:   PetscCall(STGetKSP(st,&ksp));
    132:   PetscCall(KSPGetPC(ksp,&pc));

    134:   /* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
    135:                    Apply the operator
    136:      - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */

    138:   /* sigma=0.0 */
    139:   PetscCall(STSetUp(st));
    140:   PetscCall(STGetType(st,&type));
    141:   PetscCall(PetscPrintf(PETSC_COMM_WORLD,"ST type %s\n",type));
    142:   PetscCall(PCGetOperators(pc,NULL,&Pmat));
    143:   PetscCall(MatView(Pmat,NULL));
    144:   PetscCall(STMatSolve(st,v,w));
    145:   PetscCall(VecView(w,NULL));

    147:   /* sigma=0.1 */
    148:   sigma = 0.1;
    149:   PetscCall(STSetShift(st,sigma));
    150:   PetscCall(STGetShift(st,&sigma));
    151:   PetscCall(PetscPrintf(PETSC_COMM_WORLD,"With shift=%g\n",(double)PetscRealPart(sigma)));
    152:   PetscCall(PCGetOperators(pc,NULL,&Pmat));
    153:   PetscCall(MatView(Pmat,NULL));
    154:   PetscCall(STMatSolve(st,v,w));
    155:   PetscCall(VecView(w,NULL));

    157:   PetscCall(STDestroy(&st));
    158:   PetscCall(MatDestroy(&A));
    159:   PetscCall(MatDestroy(&B));
    160:   PetscCall(MatDestroy(&C));
    161:   PetscCall(MatDestroy(&D));
    162:   PetscCall(MatDestroy(&Pa));
    163:   PetscCall(MatDestroy(&Pb));
    164:   PetscCall(MatDestroy(&Pc));
    165:   PetscCall(MatDestroy(&Pd));
    166:   PetscCall(VecDestroy(&v));
    167:   PetscCall(VecDestroy(&w));
    168:   PetscCall(SlepcFinalize());
    169:   return 0;
    170: }

    172: /*TEST

    174:    test:
    175:       suffix: 1
    176:       args: -st_type {{shift sinvert}separate output} -st_pc_type jacobi
    177:       requires: !single

    179: TEST*/