High-order method & HDF5 exporting

40 views
Skip to first unread message

Hermes Sampedro

unread,
Mar 30, 2022, 7:40:19 AM3/30/22
to deal.II User Group
Dear all, 

I want to use the function write_hdf5_parallel() with the corresponding DataOutFilter and DataOutFilterFlags to export my domain solution. I am working with higher-order methods and I can not find any option on the HDF5 format (and filter) to add the high order points to the exported vector file. Is that supported?

Thank you
Regards, 
H.

Wolfgang Bangerth

unread,
Mar 30, 2022, 4:05:56 PM3/30/22
to dea...@googlegroups.com
On 3/30/22 05:40, Hermes Sampedro wrote:
>
> I want to use the function /write_hdf5_parallel()/ with the
> corresponding/DataOutFilter/ and /DataOutFilterFlags /to export my
> domain solution. I am working with higher-order methods and I can not
> find any option on the HDF5 format (and filter) to add the high order
> points to the exported vector file. Is that supported?

When you say high order points, are you saying that you want your cells
to show up with curved edges (like is possible with VTK/VTU in recent
versions)? Or that you want each cell to be subdivided into smaller
subdivisions?

I'm not sure the former is possible in HDF5 at all.

Best
W.

--
------------------------------------------------------------------------
Wolfgang Bangerth email: bang...@colostate.edu
www: http://www.math.colostate.edu/~bangerth/

Hermes Sampedro

unread,
Mar 31, 2022, 4:30:43 AM3/31/22
to deal.II User Group
Dear Wolfgang, 

Thank you for your answer. I can see that for VTK there is the option of:
DataOutBase::VtkFlags flags;
flags.write_higher_order_cells = true;

I could not find anything similar for HDF5. When exporting the results and the mesh, I can only see the nodes corresponding to the first order, so I always get less dof than what I actually have. Is there any option to export all the corresponding dof?

Thank you
Regards, 
H

Wolfgang Bangerth

unread,
Mar 31, 2022, 10:52:08 AM3/31/22
to dea...@googlegroups.com

> Thank you for your answer. I can see that for VTK there is the option of:
> /DataOutBase::VtkFlags flags;/
> /flags.write_higher_order_cells = true;/
> /
> /
> I could not find anything similar for HDF5. When exporting the results and the
> mesh, I can only see the nodes corresponding to the first order, so I always
> get less dof than what I actually have. Is there any option to export all the
> corresponding dof?

I don't know whether it is possible at all in HDF5 to output higher order
cells, but even if it is, it is probably not implemented. But you can always
call DataOutBase::build_patches() with n_subdivisions>1. Take a look at the
documentation of that function.
Reply all
Reply to author
Forward
0 new messages