Actual source code: test8.c
slepc-3.18.0 2022-10-01
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 with selected columns.\n\n";
13: #include <slepcbv.h>
15: int main(int argc,char **argv)
16: {
17: BV X;
18: Vec v,t,z;
19: PetscInt i,j,n=20,k=8;
20: PetscViewer view;
21: PetscBool verbose,*which;
22: PetscReal norm;
23: PetscScalar alpha,*pz;
26: SlepcInitialize(&argc,&argv,(char*)0,help);
27: PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL);
28: PetscOptionsGetInt(NULL,NULL,"-k",&k,NULL);
29: PetscOptionsHasName(NULL,NULL,"-verbose",&verbose);
30: PetscPrintf(PETSC_COMM_WORLD,"Test BV orthogonalization with selected columns of length %" PetscInt_FMT ".\n",n);
32: /* Create template vector */
33: VecCreate(PETSC_COMM_WORLD,&t);
34: VecSetSizes(t,PETSC_DECIDE,n);
35: VecSetFromOptions(t);
37: /* Create BV object X */
38: BVCreate(PETSC_COMM_WORLD,&X);
39: PetscObjectSetName((PetscObject)X,"X");
40: BVSetSizesFromVec(X,t,k);
41: BVSetOrthogonalization(X,BV_ORTHOG_MGS,BV_ORTHOG_REFINE_IFNEEDED,PETSC_DEFAULT,BV_ORTHOG_BLOCK_GS);
42: BVSetFromOptions(X);
44: /* Set up viewer */
45: PetscViewerASCIIGetStdout(PETSC_COMM_WORLD,&view);
46: if (verbose) PetscViewerPushFormat(view,PETSC_VIEWER_ASCII_MATLAB);
48: /* Fill X entries */
49: for (j=0;j<k;j++) {
50: BVGetColumn(X,j,&v);
51: VecSet(v,0.0);
52: for (i=0;i<=n/2;i++) {
53: if (i+j<n) {
54: alpha = (3.0*i+j-2)/(2*(i+j+1));
55: VecSetValue(v,i+j,alpha,INSERT_VALUES);
56: }
57: }
58: VecAssemblyBegin(v);
59: VecAssemblyEnd(v);
60: BVRestoreColumn(X,j,&v);
61: }
62: if (verbose) BVView(X,view);
64: /* Orthonormalize first k-1 columns */
65: for (j=0;j<k-1;j++) {
66: BVOrthogonalizeColumn(X,j,NULL,&norm,NULL);
67: alpha = 1.0/norm;
68: BVScaleColumn(X,j,alpha);
69: }
70: if (verbose) BVView(X,view);
72: /* Select odd columns and orthogonalize last column against those only */
73: PetscMalloc1(k,&which);
74: for (i=0;i<k;i++) which[i] = (i%2)? PETSC_TRUE: PETSC_FALSE;
75: BVOrthogonalizeSomeColumn(X,k-1,which,NULL,NULL,NULL);
76: PetscFree(which);
77: if (verbose) BVView(X,view);
79: /* Check orthogonality */
80: PetscPrintf(PETSC_COMM_WORLD,"Orthogonalization coefficients:\n");
81: VecCreateSeq(PETSC_COMM_SELF,k-1,&z);
82: PetscObjectSetName((PetscObject)z,"z");
83: VecGetArray(z,&pz);
84: BVDotColumn(X,k-1,pz);
85: for (i=0;i<k-1;i++) {
86: if (PetscAbsScalar(pz[i])<5.0*PETSC_MACHINE_EPSILON) pz[i]=0.0;
87: }
88: VecRestoreArray(z,&pz);
89: VecView(z,view);
90: VecDestroy(&z);
92: BVDestroy(&X);
93: VecDestroy(&t);
94: SlepcFinalize();
95: return 0;
96: }
98: /*TEST
100: testset:
101: output_file: output/test8_1.out
102: test:
103: suffix: 1
104: args: -bv_type {{vecs contiguous svec mat}shared output}
105: test:
106: suffix: 1_cuda
107: args: -bv_type svec -vec_type cuda
108: requires: cuda
109: test:
110: suffix: 2
111: args: -bv_type {{vecs contiguous svec mat}shared output} -bv_orthog_refine never
112: requires: !single
113: test:
114: suffix: 3
115: args: -bv_type {{vecs contiguous svec mat}shared output} -bv_orthog_refine always
116: test:
117: suffix: 4
118: args: -bv_type {{vecs contiguous svec mat}shared output} -bv_orthog_type mgs
119: test:
120: suffix: 4_cuda
121: args: -bv_type svec -vec_type cuda -bv_orthog_type mgs
122: requires: cuda
124: TEST*/