Date: 2026-05-01T10:02:14+00:00

Actual source code: test2.c

      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 BV orthogonalization functions.\n\n";

     13: #include <slepcbv.h>

     15: int main(int argc,char **argv)
     16: {
     17:   BV             X,Y,Z;
     18:   Mat            M,R;
     19:   Vec            v,t,e;
     20:   PetscInt       i,j,n=20,k=8;
     21:   PetscViewer    view;
     22:   PetscBool      verbose;
     23:   PetscReal      norm,condn=1.0;
     24:   PetscScalar    alpha;

     26:   PetscFunctionBeginUser;
     27:   PetscCall(SlepcInitialize(&argc,&argv,NULL,help));
     28:   PetscCall(PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL));
     29:   PetscCall(PetscOptionsGetInt(NULL,NULL,"-k",&k,NULL));
     30:   PetscCall(PetscOptionsGetReal(NULL,NULL,"-condn",&condn,NULL));
     31:   PetscCheck(condn>=1.0,PETSC_COMM_WORLD,PETSC_ERR_USER_INPUT,"The condition number must be > 1");
     32:   PetscCall(PetscOptionsHasName(NULL,NULL,"-verbose",&verbose));
     33:   PetscCall(PetscPrintf(PETSC_COMM_WORLD,"Test BV orthogonalization with %" PetscInt_FMT " columns of length %" PetscInt_FMT ".\n",k,n));
     34:   if (condn>1.0) PetscCall(PetscPrintf(PETSC_COMM_WORLD," - Using a random BV with condition number = %g\n",(double)condn));

     36:   /* Create template vector */
     37:   PetscCall(VecCreate(PETSC_COMM_WORLD,&t));
     38:   PetscCall(VecSetSizes(t,PETSC_DECIDE,n));
     39:   PetscCall(VecSetFromOptions(t));

     41:   /* Create BV object X */
     42:   PetscCall(BVCreate(PETSC_COMM_WORLD,&X));
     43:   PetscCall(PetscObjectSetName((PetscObject)X,"X"));
     44:   PetscCall(BVSetSizesFromVec(X,t,k));
     45:   PetscCall(BVSetFromOptions(X));

     47:   /* Set up viewer */
     48:   PetscCall(PetscViewerASCIIGetStdout(PETSC_COMM_WORLD,&view));
     49:   if (verbose) PetscCall(PetscViewerPushFormat(view,PETSC_VIEWER_ASCII_MATLAB));

     51:   /* Fill X entries */
     52:   if (condn==1.0) {
     53:     for (j=0;j<k;j++) {
     54:       PetscCall(BVGetColumn(X,j,&v));
     55:       PetscCall(VecSet(v,0.0));
     56:       for (i=0;i<=n/2;i++) {
     57:         if (i+j<n) {
     58:           alpha = (3.0*i+j-2)/(2*(i+j+1));
     59:           PetscCall(VecSetValue(v,i+j,alpha,INSERT_VALUES));
     60:         }
     61:       }
     62:       PetscCall(VecAssemblyBegin(v));
     63:       PetscCall(VecAssemblyEnd(v));
     64:       PetscCall(BVRestoreColumn(X,j,&v));
     65:     }
     66:   } else PetscCall(BVSetRandomCond(X,condn));
     67:   if (verbose) PetscCall(BVView(X,view));

     69:   /* Create copies on Y and Z */
     70:   PetscCall(BVDuplicate(X,&Y));
     71:   PetscCall(PetscObjectSetName((PetscObject)Y,"Y"));
     72:   PetscCall(BVCopy(X,Y));
     73:   PetscCall(BVDuplicate(X,&Z));
     74:   PetscCall(PetscObjectSetName((PetscObject)Z,"Z"));
     75:   PetscCall(BVCopy(X,Z));

     77:   /* Test BVOrthogonalizeColumn */
     78:   for (j=0;j<k;j++) {
     79:     PetscCall(BVOrthogonalizeColumn(X,j,NULL,&norm,NULL));
     80:     alpha = 1.0/norm;
     81:     PetscCall(BVScaleColumn(X,j,alpha));
     82:   }
     83:   if (verbose) PetscCall(BVView(X,view));

     85:   /* Check orthogonality */
     86:   PetscCall(MatCreateSeqDense(PETSC_COMM_SELF,k,k,NULL,&M));
     87:   PetscCall(BVDot(X,X,M));
     88:   PetscCall(MatShift(M,-1.0));
     89:   PetscCall(MatNorm(M,NORM_1,&norm));
     90:   if (norm<100*PETSC_MACHINE_EPSILON) PetscCall(PetscPrintf(PETSC_COMM_WORLD,"Level of orthogonality < 100*eps\n"));
     91:   else PetscCall(PetscPrintf(PETSC_COMM_WORLD,"Level of orthogonality: %g\n",(double)norm));

     93:   /* Test BVOrthogonalize */
     94:   PetscCall(MatCreateSeqDense(PETSC_COMM_SELF,k,k,NULL,&R));
     95:   PetscCall(PetscObjectSetName((PetscObject)R,"R"));
     96:   PetscCall(BVOrthogonalize(Y,R));
     97:   if (verbose) {
     98:     PetscCall(BVView(Y,view));
     99:     PetscCall(MatView(R,view));
    100:   }

    102:   /* Check orthogonality */
    103:   PetscCall(BVDot(Y,Y,M));
    104:   PetscCall(MatShift(M,-1.0));
    105:   PetscCall(MatNorm(M,NORM_1,&norm));
    106:   if (norm<100*PETSC_MACHINE_EPSILON) PetscCall(PetscPrintf(PETSC_COMM_WORLD,"Level of orthogonality < 100*eps\n"));
    107:   else PetscCall(PetscPrintf(PETSC_COMM_WORLD,"Level of orthogonality: %g\n",(double)norm));

    109:   /* Check residual */
    110:   PetscCall(BVMult(Z,-1.0,1.0,Y,R));
    111:   PetscCall(BVNorm(Z,NORM_FROBENIUS,&norm));
    112:   if (norm<100*PETSC_MACHINE_EPSILON) PetscCall(PetscPrintf(PETSC_COMM_WORLD,"Residual ||X-QR|| < 100*eps\n"));
    113:   else PetscCall(PetscPrintf(PETSC_COMM_WORLD,"Residual ||X-QR||: %g\n",(double)norm));

    115:   /* Test BVOrthogonalizeVec */
    116:   PetscCall(VecDuplicate(t,&e));
    117:   PetscCall(VecSet(e,1.0));
    118:   PetscCall(BVOrthogonalizeVec(X,e,NULL,&norm,NULL));
    119:   PetscCall(PetscPrintf(PETSC_COMM_WORLD,"Norm of ones(n,1) after orthogonalizing against X: %g\n",(double)norm));

    121:   PetscCall(MatDestroy(&M));
    122:   PetscCall(MatDestroy(&R));
    123:   PetscCall(BVDestroy(&X));
    124:   PetscCall(BVDestroy(&Y));
    125:   PetscCall(BVDestroy(&Z));
    126:   PetscCall(VecDestroy(&e));
    127:   PetscCall(VecDestroy(&t));
    128:   PetscCall(SlepcFinalize());
    129:   return 0;
    130: }

    132: /*TEST

    134:    testset:
    135:       output_file: output/test2_1.out
    136:       test:
    137:          suffix: 1
    138:          args: -bv_type {{vecs contiguous svec mat}shared output} -bv_orthog_type cgs
    139:       test:
    140:          suffix: 1_cuda
    141:          args: -bv_type {{svec mat}} -vec_type cuda -bv_orthog_type cgs
    142:          requires: cuda
    143:       test:
    144:          suffix: 1_hip
    145:          args: -bv_type {{svec mat}} -vec_type hip -bv_orthog_type cgs
    146:          requires: hip
    147:       test:
    148:          suffix: 2
    149:          args: -bv_type {{vecs contiguous svec mat}shared output} -bv_orthog_type mgs
    150:       test:
    151:          suffix: 2_cuda
    152:          args: -bv_type {{svec mat}} -vec_type cuda -bv_orthog_type mgs
    153:          requires: cuda
    154:       test:
    155:          suffix: 2_hip
    156:          args: -bv_type {{svec mat}} -vec_type hip -bv_orthog_type mgs
    157:          requires: hip

    159:    test:
    160:       suffix: 3
    161:       nsize: 1
    162:       args: -bv_type {{vecs contiguous svec mat}shared output} -condn 1e8
    163:       requires: !single
    164:       filter: grep -v "against"
    165:       output_file: output/test2_3.out

    167: TEST*/