Output
=====================

Equation of State
------------------

The module writes ``eos.csv`` to the output directory. The file has no header row, and
contains the columns described in the table below.

+----------------------------------------------------+------------------+
| **Variable**                                       | **Unit**         |
+====================================================+==================+
| Temperature (T)                                    | MeV              |
+----------------------------------------------------+------------------+
| Baryon chemical potential (:math:`\mu_B`)          | MeV              |
+----------------------------------------------------+------------------+
| Strange chemical potential (:math:`\mu_S`)         | MeV              |
+----------------------------------------------------+------------------+
| Electric charge chemical potential (:math:`\mu_Q`) | MeV              |
+----------------------------------------------------+------------------+
| Baryon density (:math:`n_B`)                       | fm\ :sup:`-3`    |
+----------------------------------------------------+------------------+
| Strange density (:math:`n_S`)                      | fm\ :sup:`-3`    |
+----------------------------------------------------+------------------+
| Electric charge density (:math:`n_Q`)              | fm\ :sup:`-3`    |
+----------------------------------------------------+------------------+
| Energy density (:math:`\varepsilon`)               | MeV/fm\ :sup:`3` |
+----------------------------------------------------+------------------+
| Pressure (:math:`P`)                               | MeV/fm\ :sup:`3` |
+----------------------------------------------------+------------------+
| Entropy density (:math:`s`)                        | 1/fm\ :sup:`3`   |
+----------------------------------------------------+------------------+
| Speed of sound squared (:math:`c_s^2`)             | Dimensionless    |
+----------------------------------------------------+------------------+

Status File
-----------

The module also writes ``status.yaml`` to the output directory, with an integer code and
a message string:

.. code-block:: yaml

   code: 200
   message: Success

+------+----------------------------------------------------------------+
| Code | Meaning                                                        |
+======+================================================================+
| 200  | Success                                                        |
+------+----------------------------------------------------------------+
| 400  | Bad input (invalid ``config.yaml``, e.g. an unknown grid type) |
+------+----------------------------------------------------------------+
| 500  | Internal error during the EOS computation                      |
+------+----------------------------------------------------------------+

.. note::

   ``validate_config.py`` also writes ``status.yaml`` with code ``400`` if
   ``input/config.yaml`` fails validation against the OpenAPI schema, before
   ``interface.py`` ever runs. See :ref:`quickstart` for how the two scripts are chained.