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How to run a forward simulation using the results of an inversion
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After :doc:`running an inversion</usertutos/first-inversion/index>`, it may be useful, e.g. for evaluating the results, to run a forward simulation using the results of the inversion as inputs.

This is simply done from the yaml used for the inversion by:

  - changing the :bash:`WORKDIR`
  - changing the :doc:`mode</documentation/configuration/modes/index>` to :bash:`forward` (and, for clarity's sake, remove the arguments which are only useful for the inversion such as the :bash:`minimizer`). Add the optional argumemnt :bash:`use_xb: False` so that the output fiels are NOT created using the prior state.
  - in :doc:`controlvect</documentation/plugins/controlvects/index>`, add optional arguments :bash:`reload_xb: True` and  :bash:`reload_file` to provide the path to the pickle file where the controlvects are stored. It probably is $WORKDIR_inversion/controlvect_final.pickle.
  - change the components of the :doc:`datavect</documentation/plugins/datavects/index>` which are not to be the same as in the inversion e.g. :doc:`concs</documentation/plugins/datavects/standard>` or :doc:`satellites</documentation/plugins/transforms/complex/satellites>` for comparing to other data than the assimilated ones.