bool HostMatrixCOO<ValueType>::Permute(const BaseVector<int> &permutation) {
assert(&permutation != NULL);
// symmetric permutation only
assert( (permutation.get_size() == this->get_nrow()) &&
(permutation.get_size() == this->get_ncol()) );
const HostVector<int> *cast_perm = dynamic_cast<const HostVector<int>*> (&permutation) ;
assert(cast_perm != NULL);
HostMatrixCOO<ValueType> src(this->local_backend_);
src.AllocateCOO(this->get_nnz(), this->get_nrow(), this->get_ncol());
src.CopyFrom(*this);
omp_set_num_threads(this->local_backend_.OpenMP_threads);
#pragma omp parallel for
for (int i=0; i<this->get_nnz(); ++i) {
this->mat_.row[i] = cast_perm->vec_[ src.mat_.row[i] ];
this->mat_.col[i] = cast_perm->vec_[ src.mat_.col[i] ];
}
return true;
}
bool HostMatrixCOO<ValueType>::PermuteBackward(const BaseVector<int> &permutation) {
assert(&permutation != NULL);
// symmetric permutation only
assert( (permutation.get_size() == this->nrow_) &&
(permutation.get_size() == this->ncol_) );
const HostVector<int> *cast_perm = dynamic_cast<const HostVector<int>*> (&permutation);
assert(cast_perm != NULL);
HostMatrixCOO<ValueType> src(this->local_backend_);
src.AllocateCOO(this->nnz_, this->nrow_, this->ncol_);
src.CopyFrom(*this);
_set_omp_backend_threads(this->local_backend_, this->nnz_);
// TODO
// Is there a better way?
int *pb = NULL;
allocate_host(this->nrow_, &pb);
#pragma omp parallel for
for (int i=0; i<this->nrow_; ++i)
pb [ cast_perm->vec_[i] ] = i;
#pragma omp parallel for
for (int i=0; i<this->nnz_; ++i) {
this->mat_.row[i] = pb[src.mat_.row[i]];
this->mat_.col[i] = pb[src.mat_.col[i]];
}
free_host(&pb);
return true;
}
