= PDAF3_put_state_global =

This page documents the routine `PDAF3_put_state_global` of PDAF. The routine is part of the advanced [wiki:PDAF3_interface PDAF3 interface] that was introduced with PDAF V3.0.

The routine is used to execute the analysis step of all global ensemble filters (including the NETF and PF) and the local EnKF. The routine uses the functionalities provided by PDAF-OMI to yield a minimum number of arguments.

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

The general aspects of the filter specific routines `PDAF3_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 for the offline mode of PDAF. It can also be used in the 'flexible' parallelization implementation variant of the data assimilation system, but starting with PDAF-3 we recommend to use [wiki:PDAF3_assimilate_global PDAF3_assimilate_global], which is also used with the 'fully-parallel' implementation variant.

The interface for using the global filters is:
{{{
  SUBROUTINE PDAF3_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.

**Note:**
 * The routine is identical to the routine `PDAFomi_put_state_global` of PDAF 2. The new name reflect consistency with `PDAF3_assimilate_global`. If one has used `PDAFomi_put_state_global` before one can just adapt the name of the called routine.

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.