= PDAFomi_put_state_global =

This page documents the routine `PDAF_put_state_global` of PDAF. The routine is used to execute the analysis step of all global ensemble filters (including the NETF and PF) with PDAF-OMI.

The routine is typically called in `assimilate_pdaf` or directly in the model code.

The general aspects of the filter specific routines `PDAFomi_put_state_*` are described on the page [ModifyModelforEnsembleIntegration Modification of the model code for the ensemble integration] and its sub-page on [InsertAnalysisStep inserting the analysis step]. The routine is used in the 'flexible' parallelization implementation variant of the data assimilation system. With the 'fully-parallel' implementation variant, the routine [wiki:PDAFomi_assimilate_global PDAFomi_assimilate_global] is used. 

Here, we list the full interface of the routine. 

The interface for using the global filters is:
{{{
  SUBROUTINE PDAFomi_put_state_global(U_collect_state, &
                                 U_init_dim_obs_pdafomi, U_obs_op_pdafomi, &
                                 U_prepoststep, status)
}}}
with the following arguments:
 * `U_collect_state`: The name of the user-supplied routine that initializes a state vector from the array holding the ensemble of model states from the model fields. This is basically the inverse operation to `U_distribute_state` used in `PDAF_get_state` as well as here. 
 * `U_init_dim_obs_pdafomi`: The name of the user-supplied routine that initializes the observation information and provides the size of observation vector
 * `U_obs_op_pdafomi`: The name of the user-supplied routine that acts as the observation operator on some state vector
 * `U_prepoststep`: The name of the pre/poststep routine as in `PDAF_get_state`
 * `status`: The integer status flag. It is zero, if `PDAFomi_put_state_global` is exited without errors.

The user-supplied call-back routines are described on the page on [ImplementAnalysisGlobal implementing the analysis step of the global filters].

It is recommended that the value of `status_pdaf` is checked in the program after PDAFomi_assimilate_global is executed. Only if its value is 0 the initialization was successful.

PDAF also has a [PdafSimplifiedInterface Simplified Interface] providing the routine `PDAFomi_put_state_global_si`. In the simplified interface, the name of the user-supplied routines have predefined names and do not appear in the call to `PDAFomi_put_state_global_si`.  More information on the pre-defined names is provided in the [ImplementAnalysisGlobal page on implementing the analysis step of the global filters].