= PDAFlocalomi_put_state_lknetf_nondiagR =

This page documents the routine `PDAFlocalomi_put_state_lknetf_nondiagR` of PDAF. The routine is used to execute the analysis step of the local nonlinear ensemble transform filter LKNETF with PDAF-OMI for the case of a non-diagonal observation error covariance matrix. This routine was introduced with PDAF V2.3.

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

The routines `PDAF_put_state_*` are used with the 'flexible' implementation variant of PDAF. 
The general aspects of the filter specific routines `PDAF_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]. For the 'fully parallel' implementation variant the alternative routines `PDAF_assimilate_*` are used.

The interface for the routine `PDAFlocalomi_put_state_lknetf_nondiagR` contains names for routines that operate on the local analysis domains (marked by the suffix `_l`). 
Here, we list the full interface of the routine. Subsequently, the user-supplied routines specified in the call is explained. 

The interface when using the LKNETF is the following:
{{{
  SUBROUTINE PDAFomi_put_state_lknetf_nondiagR(U_collect_state,&
                                  U_init_dim_obs_pdafomi, U_obs_op_pdafomi, &
                                  U_prepoststep, U_init_n_domains, U_init_dim_l, &
                                  U_init_dim_obs_l_pdafomi, &
                                  U_prodRinvA_l_pdafomi, U_prodRinvA_hyb_l_pdafomi, &
                                  U_likelihood_l_pdafomi, U_likelihood_l_pdafomi, &
                                  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 [ModifyModelforEnsembleIntegration#PDAF_get_state PDAF_get_state] and also 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`
 * `U_init_n_domains`: The name of the routine that provides the number of local analysis domains
 * `U_init_dim_l`: The name of the routine that provides the state dimension for a local analysis domain
 * `U_init_dim_obs_l_pdafomi`: The name of the routine that initializes the size of the observation vector for a local analysis domain
 * `U_prodRinvA_l_pdafomi`: The name of the user-supplied routine that computes the product of the inverse of the observation error covariance matrix with some matrix provided to the routine by PDAF.
 * `U_prodRinvA_hyb_l_pdafomi`: The name of the user-supplied routine that computes the product of the inverse of the observation error covariance matrix with some matrix provided to the routine by PDAF including the hybrid weight.
 * `U_likelihood_l_pdafomi`: The name of the user-supplied routine that computes the local likelihood of an ensemble state.
 * `U_likelihood_hyb_l_pdafomi`: The name of the user-supplied routine that computes the local likelihood of an ensemble state including the hybrid weight.
 * `status`: The integer status flag. It is zero, if this routine is exited without errors.

Notes:
 * The order of the routine names does not show the order in which these routines are executed. See the [ImplementAnalysisLocal#Executionorderofuser-suppliedroutines section on the order of the execution] on the page on implementing the analysis step of the local filter algorithms. 
 * The difference to the routine `PDAFlocalomi_put_state` used for diagonal R-matrices is in the additonal arguments `U_likelihood_l_pdafomi`,  `U_likelihood_hyb_l_pdafomi`,  `U_prodRinvA_l_pdafomi`,  `U_prodRinvA_hyb_l_pdafomi`.
 * The local filters LESTKF, LETKF, and LSEIK use the separate routine [wiki:PDAFlocalomi_put_state_nondiagR].
 * The filter LNETF uses the separate routine [wiki:PDAFlocalomi_put_state_lnetf_nondiagR]

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

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

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