###################
Observation vectors
###################

.. role:: bash(code)
      :language: bash


.. role:: raw-math(raw)
    :format: latex html


In pyCIF, the observation vector :math:`\mathbf{y}` is stored as a folder, with a
structure by type of observation and species. Therein, individual files follow a format
similar to the :doc:`one expected to provide observations <monitor>`.

::

    obsvect folder
    ├── obs type #1
    │   ├── species #1
    │   │   └── monitor.nc
    │   └── species #2f
    │       └── monitor.nc
    └── obs type #2
        ├── species #1
        │   └── monitor.nc
        └── species #2
            └── monitor.nc

NetCDF format
^^^^^^^^^^^^^

NetCDF :bash:`monitor.nc` in the observation vector use the group features to separate
different types of observations.

By default there are two groups of information:

:maindata:
        it includes the observations, observation errors, simulated equivalents, increments
        in the case of the tangent-linear and adjoint sensitivities

:metadata:
        it includes all other information, including the date, longitude, latitude, etc.
        of the corresponding observation
        
Each output :bash:`monitor.nc` file is then formatted as illustrated in the following example:

.. literalinclude:: dump_monitor.txt