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lines 6-82 of file: at_cascade/get_cov_info.py
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{xrst_begin get_cov_info}
{xrst_spell
  rel
}

Get Covariate Information
#########################

Prototype
*********
{xrst_literal ,
   # BEGIN_DEF, # END_DEF
   # BEGIN_RETURN, # END_RETURN
}

option_all_table
****************
This is the :ref:`option_all_table-name` as a python list
of python dictionaries.
This argument can't be ``None``.

covariate_table
***************
This is the dismod_at covariate table as a python list
of python dictionaries.
This argument can't be ``None``.

split_reference_table
*********************
This is the :ref:`split_reference_table-name` as a python list
of python dictionaries.
This argument can't be ``None``.

cov_info
********
The return value *cov_info* is a `dict` with the following keys:

abs_covariate_id_set
====================
if *key* is abs_covariate_id_set, *cov_info[key]* is a ``set`` of ``int``.
A covariate_id is in this set if and only if the corresponding
covariate name is in :ref:`option_all_table@absolute_covariates`.
If absolute_covariates does not appear in the option_all table,
*cov_info[key]* is the empty set.
The reference value for these absolute covariates is the same
for all nodes and all values of the splitting covariate.

rel_covariate_id_set
====================
if *key* is rel_covariate_id_set, *cov_info[key]* is a set of ``int``.
This is the set of covariate_id values corresponding to the
:ref:`relative covariates<glossary@Relative Covariate>`.

split_covariate_id
==================
If :ref:`split_reference_table-name` is empty, this key is not present.
Otherwise, for *key* equal to split_covariate_id, *cov_info[key]* is an ``int``
equal to the covariate_id corresponding to the
:ref:`option_all_table@split_covariate_name`.

split_reference_list
====================
If :ref:`split_reference_table-name` is empty, this key is not present.
Otherwise, for *key* equal to split_reference_list, *cov_info[key]* is a
``list`` of ``float`` representation of
:ref:`split_reference_table@split_reference_value` in the
same order as they appear in the table.

split_reference_id
==================
If :ref:`split_reference_table-name` is empty, this key is not present.
Otherwise, for *key* equal to split_reference_id, *cov_info[key]* is an ``int``
containing an index in the split_reference_list.
The corresponding value in split_reference_list is equal to
the reference value for split_covariate_name in the covariate table.

{xrst_end get_cov_info}