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lines 16-120 of file: devel/cmd/init_command.cpp
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{xrst_begin init_command}

The Initialize Command
######################

Syntax
******
``dismod_at`` *database* ``init``

Purpose
*******
This command initializes the data flow.
To be specific, it begins by deleting any existing output tables,
except for the log table,
and then creates new versions of the following tables:

.. csv-table::
   :widths: auto

   age_avg_table,:ref:`age_avg_table-title`
   bnd_mulcov_table,:ref:`bnd_mulcov_table-title`
   data_subset_table,:ref:`data_subset_table-title`
   start_var_table,:ref:`start_var_table-title`
   scale_var_table,:ref:`scale_var_table-title`
   var_table,:ref:`var_table-title`

Deleted Tables
**************
This routine begins by deleting any existing
:ref:`output tables<data_flow@Output Tables by Table Name>` ,
except for the :ref:`log_table-name` .

Changing Values
***************
You must re-run this command when ever any of the
:ref:`input-name` tables is changed.
The option table is an exception to this rule; see
:ref:`option_table@Changing Values` .

database
********
Is an
`sqlite <https://sqlite.org/index.html>`_ database containing the
``dismod_at`` :ref:`input-name` tables which are not modified.

age_avg_table
*************
A new :ref:`age_avg_table-name` is created when this command is run.
In fact, this table is recreated when any command is run except for the
python commands and the :ref:`set_command-name` .

var_table
*********
A new :ref:`var_table-name` is created with the information
that maps a :ref:`var_table@var_id`
to its meaning in terms of the
:ref:`model_variables-name` .

data_subset_table
*****************
A new :ref:`data_subset_table-name` is created.
This makes explicit exactly which rows of the data table are used.

hold_out
========
This column is set to zero.

density_id
==========
This column is set to the corresponding
:ref:`data_table@density_id` in the data table.

eta
===
This column is set to the corresponding
:ref:`data_table@eta` in the data table.

nu
==
This column is set to the corresponding
:ref:`data_table@nu` in the data table.

start_var_table
***************
A new :ref:`start_var_table-name` is created using the
means of the priors for the model variables.

scale_var_table
***************
A new :ref:`scale_var_table-name` is created using the
means of the priors for the model variables.

bnd_mulcov_table
****************
A new bnd_mulcov table is created using null for
:ref:`bnd_mulcov_table@max_mulcov` ; i.e., plus infinity.
{xrst_toc_hidden
   example/get_started/init_command.py
}
Example
*******
The file :ref:`init_command.py-name` contains an example and test
using this command.

{xrst_end init_command}