===============================
NPD data for VEX (experimental)
===============================

``irfpy.aspera`` support the NPD data access interface.

NPD is an ENA detector, which has energy and mass analysis.
More details, see Barabash et al., 2007.


.. warning::

        The NPD data is highly tricky.
        A lot of considerations with instrument and data characteristics
        knowledge must be included for interpretation.

        It is strongly recommended to contact to Futaana or relevant
        scientists for the use of the data.

Setup the dataset
=================

The dataset is provided as a multiple netcdf files.
Copy the dataset into a single folder.

The folder should be specified in the ``~/.irfpyrc`` file.  Add below.

::

    [vnpd]
    ncdfbase = /path/to/ncdf

Testing the setup
=================

Try the followings in the python console.

>>> from irfpy.vnpd import vnpddata
>>> dc = vnpddata.DataCenterRawMode(1)
>>> import datetime
>>> t0 = datetime.datetime(2009, 1, 4, 21, 27, 30)
>>> print(dc.nearest(t0))
(datetime.datetime(2009, 1, 4, 21, 27, 30, 242400), <NpdRawPacket: 2009-01-04T21:27:30 cnts=103 147 204 79 1 400>)


Troubleshoot
============

1. *Installation of ``irfpy.aspera``?*

   - See :ref:`quickinstall`.

2. *Dataset setup*

   - See if ``.irfpyrc`` file exists, and the following statement is described.

     ::

        [vnpd]
        ncdfbase = /path/to/ncdf

   - See if the above path (``/path/to/ncdf``) exists, and contains the dataset.

3. Ask to the developer (Futaana).


TOC
===

.. toctree::
   :maxdepth: 1
   :glob:

   tutorial_35??_*