.. _export_hdf5:

Export to HDF5
=================

.. warning:: This tool is under construction and will not function for all data types.

This tool exports FLO-2D files into an HDF5 file.

Export the FLO-2D files into a HDF5 file
-----------------------------------------

.. note:: Set the Control Variables switches before running the Export tool.
          See `Set Control Parameters (CONT.DAT) <../flo-2d-parameters/Control%20Variables.html>`__.

1. Click the
   Export to HDF5.

.. image:: ../../img/Buttons/importexport005.png

2. Navigate to
   the export folder, set the file name, and click Save.

.. image:: ../../img/Export-to-Hdf5/exporthdf5001.png

3. The Export to HDF5 dialog will appear.
   Select the data you want to export and click OK. A progress bar will appear while the export is in progress.

.. image:: ../../img/Export-to-Hdf5/exphdf003.png

4. A message at the QGIS toolbar will show that the file was correctly exported.

.. image:: ../../img/Export-to-Hdf5/exporthdf5002.png


HDF5 Data Structure
-----------------------------------------

The program HDFView can be used to view the HDF5 file structure. The HDF5 file contains groups of datasets that 
flopro.exe reads to run the FLO-2D model. The datasets are organized in a way that is simpler than the original FLO-2D files, but still contains all the necessary information.

The HDF5 file will expand as more tables are added.  The follwoing image shows the structure of an HDF5 with a grid and control data.

.. image:: ../../img/Export-to-Hdf5/hdf001.png

The tables are relatively simple as you can see in the coordinates table below. The coordinates table contains the x and y coordinates of the grid nodes.

.. image:: ../../img/Export-to-Hdf5/hdf002.png

.. |hdfview| raw:: html

    <a href="https://www.hdfgroup.org/downloads/hdfview/" target="_blank" rel="noopener">HDFView</a>

|hdfview| can be downloaded from the HDF Group website.

See the :ref:`Technical Reference Manual <tech_ref_manual>` Appendix C for more details on the HDF5 file structure.

.. note:: The HDF5 file format is a binary format, so it cannot be opened in a text editor. It must be opened with a program that can read HDF5 files, such as HDFView.