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 DSNHEP.\n\n";

 13: #include <slepcds.h>

 15: int main(int argc,char **argv)
 16: {
 17:   DS             ds;
 18:   SlepcSC        sc;
 19:   DSType         type;
 20:   DSStateType    state;
 21:   PetscScalar    *A,*X,*Q,*wr,*wi,d;
 22:   PetscReal      re,im,rnorm,aux;
 23:   PetscInt       i,j,n=10,ld,method;
 24:   PetscViewer    viewer;
 25:   PetscBool      verbose,extrarow;

 27:   PetscFunctionBeginUser;
 28:   PetscCall(SlepcInitialize(&argc,&argv,NULL,help));
 29:   PetscCall(PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL));
 30:   PetscCall(PetscPrintf(PETSC_COMM_WORLD,"Solve a Dense System of type NHEP - dimension %" PetscInt_FMT ".\n",n));
 31:   PetscCall(PetscOptionsHasName(NULL,NULL,"-verbose",&verbose));
 32:   PetscCall(PetscOptionsHasName(NULL,NULL,"-extrarow",&extrarow));

 34:   /* Create DS object */
 35:   PetscCall(DSCreate(PETSC_COMM_WORLD,&ds));
 36:   PetscCall(DSSetType(ds,DSNHEP));
 37:   PetscCall(DSSetFromOptions(ds));
 38:   ld = n+2;  /* test leading dimension larger than n */
 39:   PetscCall(DSAllocate(ds,ld));
 40:   PetscCall(DSSetDimensions(ds,n,0,0));
 41:   PetscCall(DSSetExtraRow(ds,extrarow));

 43:   /* Set up viewer */
 44:   PetscCall(PetscViewerASCIIGetStdout(PETSC_COMM_WORLD,&viewer));
 45:   PetscCall(PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_INFO_DETAIL));
 46:   PetscCall(DSView(ds,viewer));
 47:   PetscCall(PetscViewerPopFormat(viewer));
 48:   if (verbose) PetscCall(PetscViewerPushFormat(viewer,PETSC_VIEWER_ASCII_MATLAB));

 50:   /* Fill with Grcar matrix */
 51:   PetscCall(DSGetArray(ds,DS_MAT_A,&A));
 52:   for (i=1;i<n;i++) A[i+(i-1)*ld]=-1.0;
 53:   for (j=0;j<4;j++) {
 54:     for (i=0;i<n-j;i++) A[i+(i+j)*ld]=1.0;
 55:   }
 56:   if (extrarow) A[n+(n-1)*ld]=-1.0;
 57:   PetscCall(DSRestoreArray(ds,DS_MAT_A,&A));
 58:   PetscCall(DSSetState(ds,DS_STATE_INTERMEDIATE));
 59:   if (verbose) {
 60:     PetscCall(PetscPrintf(PETSC_COMM_WORLD,"Initial - - - - - - - - -\n"));
 61:     PetscCall(DSView(ds,viewer));
 62:   }

 64:   /* Solve */
 65:   PetscCall(PetscMalloc2(n,&wr,n,&wi));
 66:   PetscCall(DSGetSlepcSC(ds,&sc));
 67:   sc->comparison    = SlepcCompareLargestMagnitude;
 68:   sc->comparisonctx = NULL;
 69:   sc->map           = NULL;
 70:   sc->mapobj        = NULL;
 71:   PetscCall(DSSolve(ds,wr,wi));
 72:   PetscCall(DSSort(ds,wr,wi,NULL,NULL,NULL));
 73:   if (extrarow) PetscCall(DSUpdateExtraRow(ds));

 75:   PetscCall(DSGetType(ds,&type));
 76:   PetscCall(DSGetMethod(ds,&method));
 77:   PetscCall(PetscPrintf(PETSC_COMM_WORLD,"DS of type %s, method used=%" PetscInt_FMT "\n",type,method));
 78:   PetscCall(DSGetState(ds,&state));
 79:   PetscCall(PetscPrintf(PETSC_COMM_WORLD,"State after solve: %s\n",DSStateTypes[state]));

 81:   if (verbose) {
 82:     PetscCall(PetscPrintf(PETSC_COMM_WORLD,"After solve - - - - - - - - -\n"));
 83:     PetscCall(DSView(ds,viewer));
 84:   }

 86:   /* Print eigenvalues */
 87:   PetscCall(PetscPrintf(PETSC_COMM_WORLD,"Computed eigenvalues =\n"));
 88:   for (i=0;i<n;i++) {
 89: #if defined(PETSC_USE_COMPLEX)
 90:     re = PetscRealPart(wr[i]);
 91:     im = PetscImaginaryPart(wr[i]);
 92: #else
 93:     re = wr[i];
 94:     im = wi[i];
 95: #endif
 96:     if (PetscAbs(im)<1e-10) PetscCall(PetscViewerASCIIPrintf(viewer,"  %.5f\n",(double)re));
 97:     else PetscCall(PetscViewerASCIIPrintf(viewer,"  %.5f%+.5fi\n",(double)re,(double)im));
 98:   }

100:   if (extrarow) {
101:     /* Check that extra row is correct */
102:     PetscCall(DSGetArray(ds,DS_MAT_A,&A));
103:     PetscCall(DSGetArray(ds,DS_MAT_Q,&Q));
104:     d = 0.0;
105:     for (i=0;i<n;i++) d += A[n+i*ld]+Q[n-1+i*ld];
106:     if (PetscAbsScalar(d)>10*PETSC_MACHINE_EPSILON) PetscCall(PetscPrintf(PETSC_COMM_WORLD,"Warning: there is a mismatch in the extra row of %g\n",(double)PetscAbsScalar(d)));
107:     PetscCall(DSRestoreArray(ds,DS_MAT_A,&A));
108:     PetscCall(DSRestoreArray(ds,DS_MAT_Q,&Q));
109:   }

111:   /* Eigenvectors */
112:   j = 2;
113:   PetscCall(DSVectors(ds,DS_MAT_X,&j,&rnorm));  /* third eigenvector */
114:   PetscCall(PetscPrintf(PETSC_COMM_WORLD,"Value of rnorm for 3rd vector = %.3f\n",(double)rnorm));
115:   PetscCall(DSVectors(ds,DS_MAT_X,NULL,NULL));  /* all eigenvectors */
116:   j = 0;
117:   rnorm = 0.0;
118:   PetscCall(DSGetArray(ds,DS_MAT_X,&X));
119:   for (i=0;i<n;i++) {
120: #if defined(PETSC_USE_COMPLEX)
121:     aux = PetscAbsScalar(X[i+j*ld]);
122: #else
123:     if (PetscAbs(wi[j])==0.0) aux = PetscAbsScalar(X[i+j*ld]);
124:     else aux = SlepcAbsEigenvalue(X[i+j*ld],X[i+(j+1)*ld]);
125: #endif
126:     rnorm += aux*aux;
127:   }
128:   PetscCall(DSRestoreArray(ds,DS_MAT_X,&X));
129:   rnorm = PetscSqrtReal(rnorm);
130:   PetscCall(PetscPrintf(PETSC_COMM_WORLD,"Norm of 1st vector = %.3f\n",(double)rnorm));
131:   if (verbose) {
132:     PetscCall(PetscPrintf(PETSC_COMM_WORLD,"After vectors - - - - - - - - -\n"));
133:     PetscCall(DSView(ds,viewer));
134:   }

136:   PetscCall(PetscFree2(wr,wi));
137:   PetscCall(DSDestroy(&ds));
138:   PetscCall(SlepcFinalize());
139:   return 0;
140: }

142: /*TEST

144:    testset:
145:       filter: sed -e "s/[+-]\([0-9]\.[0-9]*i\)/+-\\1/" | sed -e "s/extrarow//"
146:       output_file: output/test1_1.out
147:       requires: !single
148:       test:
149:          suffix: 1
150:       test:
151:          suffix: 2
152:          args: -extrarow

154: TEST*/