| | 1 | = PDAFomi_assimilate_lnetf_nondiagR = |
| | 2 | |
| | 3 | This page documents the routine `PDAFomi_assimilate_lnetf_nondiagR` of PDAF. The routine is used to execute the analysis step of the local nonlinear ensemble transform filter LNETF with PDAF-OMI for the case of a non-diagonal observation error covariance matrix. This routine was introduced with PDAF V2.3. |
| | 4 | |
| | 5 | The routine is typically called in `assimilate_pdaf` or directly in the model code. |
| | 6 | |
| | 7 | The general aspects of the filter specific routines `PDAFomi_assimilate_*` 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 fully-parallel implementation variant of the data assimilation system. When the 'flexible' implementation variant, the routine [wiki:PDAFomi_put_state_lnetf_nondiagR PDAFomi_put_state_lnetf_nondiagR] is used. |
| | 8 | |
| | 9 | The interface for the routine `PDAFomi_assimilate_lnetf_nondiagR` contains names for routines that operate on the local analysis domains (marked by the suffix `_l`). Further there are routines that convert between a local and a global model state vector (`U_g2l_state` and `U_l2g_state`). |
| | 10 | Here, we list the full interface of the routine. Subsequently, the user-supplied routines specified in the call is explained. |
| | 11 | |
| | 12 | The interface when using the LNETF is the following: |
| | 13 | {{{ |
| | 14 | SUBROUTINE PDAFomi_assimilate_lnetf(U_collect_state, U_distribute_state, & |
| | 15 | U_init_dim_obs_pdafomi, U_obs_op_pdafomi, & |
| | 16 | U_prepoststep, U_init_n_domains, U_init_dim_l, & |
| | 17 | U_init_dim_obs_l_pdafomi, U_likelihood_l_pdafomi, & |
| | 18 | U_g2l_state, U_l2g_state, & |
| | 19 | U_next_observation, status) |
| | 20 | }}} |
| | 21 | with the following arguments: |
| | 22 | * `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. |
| | 23 | * `U_distribute_state`: The name of a user supplied routine that initializes the model fields from the array holding the ensemble of model state vectors. |
| | 24 | * `U_init_dim_obs_pdafomi`: The name of the user-supplied routine that initializes the observation information and provides the size of observation vector |
| | 25 | * `U_obs_op_pdafomi`: The name of the user-supplied routine that acts as the observation operator on some state vector |
| | 26 | * `U_prepoststep`: The name of the pre/poststep routine as in `PDAF_get_state` |
| | 27 | * `U_init_n_domains`: The name of the routine that provides the number of local analysis domains |
| | 28 | * `U_init_dim_l`: The name of the routine that provides the state dimension for a local analysis domain |
| | 29 | * `U_init_dim_obs_l_pdafomi`: The name of the routine that initializes the size of the observation vector for a local analysis domain |
| | 30 | * `U_likelihood_l_pdafomi`: The name of the user-supplied routine that computes the local likelihood of an ensemble state. |
| | 31 | * `U_g2l_state`: The name of the routine that initializes a local state vector from the global state vector |
| | 32 | * `U_l2g_state`: The name of the routine that initializes the corresponding part of the global state vector from the provided local state vector |
| | 33 | * `U_next_observation`: The name of a user supplied routine that initializes the variables `nsteps`, `timenow`, and `doexit`. The same routine is also used in `PDAF_get_state`. |
| | 34 | * `status`: The integer status flag. It is zero, if `PDAFomi_assimilate_lnetf_nondiagR` is exited without errors. |
| | 35 | |
| | 36 | Notes: |
| | 37 | * 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. |
| | 38 | * The difference to the routine `PDAFomi_assimilate_local` used for diagdonal R-matrices is only in the additonal argument `U_likelihood_l_pdafomi`. |
| | 39 | * The local filters LESTKF, LETKF, and LSEIK use the separate routine [wiki:PDAFomi_assimilate_local_nondiagR PDAFomi_assimilate_local_nondiagR]. |
| | 40 | * he filter LKNETF uses the separate routine [wiki:PDAFomi_assimilate_llnetf_nondiagR PDAFomi_assimilate_lknetf_nondiagR] |
| | 41 | |
| | 42 | The user-supplied call-back routines are described on the page on [ImplementAnalysisLocal implementing the analysis step of the local filters]. |
| | 43 | |
| | 44 | It is recommended that the value of `status_pdaf` is checked in the program after PDAFomi_assimilate_local is executed. Only if its value is 0 the initialization was successful. |
| | 45 | |
| | 46 | PDAF also has a [PdafSimplifiedInterface Simplified Interface] providing the routine `PDAFomi_assimilate_lnetf_nondiagR_si`. In the simplified interface, the name of the user-supplied routines have predefined names and do not appear in the call to `PDAFomi_assimilate_lnetf_nondiagR_si`. More information on the pre-defined names is provided in the [ImplementAnalysisLocal page on implementing the analysis step of the local filters]. |
| | 47 | |
