Actual source code: test1.c

slepc-3.17.2 2022-08-09
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 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:   SlepcInitialize(&argc,&argv,(char*)0,help);
 28:   PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL);
 29:   PetscPrintf(PETSC_COMM_WORLD,"Solve a Dense System of type NHEP - dimension %" PetscInt_FMT ".\n",n);
 30:   PetscOptionsHasName(NULL,NULL,"-verbose",&verbose);
 31:   PetscOptionsHasName(NULL,NULL,"-extrarow",&extrarow);

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

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

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

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

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

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

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

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

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

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

141: /*TEST

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

153: TEST*/