Before running the full simulation
##################################

.. _Doing a dry run:

Doing a dry run
===============

By setting the :bash:`dryrun` argument to ``true``, the ``response-functions``
mode initializes the response functions, skips the reference forward simulation,
and forces a dump of all response function control vector files and YAML configuration files.

This is mainly useful for counting the number of response functions (or the number of
sampling batches).

Only running the first control vector period
============================================

By setting the :bash:`first_period_only` argument to ``true``, all response functions
whose simulation window does not start at :bash:`datei` are skipped,
resulting in **only the first time period of each control vector tracer being run**.

This option provides a quick estimate of the total computing time
and allows testing whether the :bash:`spin_down` value is appropriate.