message: Fbcsr write now writes in row-major order
diff: @@ -393,9 +393,9 @@ void Fbcsr<ValueType, IndexType>::write(mat_data &data) const
  const auto start = tmp->row_ptrs_.get_const_data()[brow];
  const auto end = tmp->row_ptrs_.get_const_data()[brow + 1];
  - for (auto inz = start; inz < end; ++inz) {
  for (int ib = 0; ib < bs_; ib++) {
  const auto row = brow * bs_ + ib;
  + for (auto inz = start; inz < end; ++inz) {
  for (int jb = 0; jb < bs_; jb++) {
  const auto col =
  tmp->col_idxs_.get_const_data()[inz] * bs_ + jb;
  