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    "# Reading and Writing Files\n",
    "\n",
    "## HDF5\n",
    "\n",
    "Scipp supports writing variables, data arrays, and dataset to [HDF5](https://portal.hdfgroup.org/display/support/Documentation) files.\n",
    "Reading of HDF5 is supported *only* for these scipp-specific files.\n",
    "Other HDF5-based formats are not supported at this point.\n",
    "For reading the HDF5-based [NeXus](https://www.nexusformat.org/) files, see [scippneutron](https://scipp.github.io/scippneutron/).\n",
    "\n",
    "<div class=\"alert alert-warning\">\n",
    "\n",
    "**Warning**\n",
    "    \n",
    "We do not recommend to use scipp HDF5 files for archiving or as the sole means of storing valuable data.\n",
    "The current scipp HDF5 schema is not a standard and will likely be subject to change due to the early development status of scipp.\n",
    "**Future versions of scipp may not be able to read older files.**\n",
    "    \n",
    "That being said, the file format is quite simple and based on the HDF5 standard so it would still be possible to recover data from such files in such a case.\n",
    "Note that the scipp version is stored as an HDF5 attribute of the saved objects.\n",
    "    \n",
    "</div>"
   ]
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  {
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   "source": [
    "import numpy as np\n",
    "import scipp as sc\n",
    "\n",
    "x = sc.Variable(dims=['x'], values=np.arange(10))\n",
    "var = sc.Variable(dims=['x', 'y'], values=np.random.rand(9,3))\n",
    "a = sc.DataArray(data=var, coords={'x':x})\n",
    "\n",
    "a.to_hdf5(filename='test.hdf5')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "b = sc.io.open_hdf5(filename='test.hdf5')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "b"
   ]
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   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## NeXus\n",
    "\n",
    "Scipp has no built-in support for loading [NeXus](https://www.nexusformat.org/) files.\n",
    "However, the `scippneutron` package can internally use [Mantid](https://www.mantidproject.org/Main_Page) to load such files, or any other Mantid-supported file type, see [scippneutron](https://scipp.github.io/scippneutron/) and in particular [scippneutron.load](https://scipp.github.io/scippneutron/generated/scippneutron.load.html#scippneutron.load)."
   ]
  }
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