= PDAF_get_state_si = This page documents the routine `PDAF_get_state_si` of PDAF. `PDAF_get_state_si` is the variant of [wiki:PDAF_get_state PDAF_get_state] with the [PdafSimplifiedInterface simplified interface]. The difference between both routines is that in the simplified interface the names of the call-back subroutines are not specified. Instead the routine assumes that the call-back routines have a standard name as specified at the end of this page. The routine `PDAF_get_state_si` has to be called once at the end of the initialization of PDAF. Usually, the call will be added to the routine `init_pdaf` that is discussed on the [InitPdaf page on initializing PDAF]. The routine `PDAF_get_state_si` has the purpose to initialize the model fields to be propagates from the array holding the ensemble states. In addition, the routine can initialized the information, whether further model integrations have to be computed and how many time steps have to be performed. For the fully-parallel implementation variant, the number of time steps is used inside PDAF, while the flag on further model integrations is not used. The interface of `PDAF_get_state_si` is the following: {{{ SUBROUTINE PDAF_get_state_si(nsteps, timenow, doexit, status) }}} with the following arguments: * `nsteps`: An integer specifying upon exit the number of time steps to be performed * `timenow`: A real specifying upon exit the current model time. (This value is usually not used in the fully-parallel implemenation variant) * `doexit`: An integer variable defining whether the assimilation process is completed. For compatibility 1 should be used for exit, 0 for continuing. (This value is not used in the fully-parallel implemenation variant) * `status`: The integer status flag. It is zero, if `PDAF_get_state` is exited without errors. The routine `PDAF_get_state_si` call the three user-supplied routines `U_next_observation`, `U_distribute_state`, `U_prepoststep`. They are documented on the page on [InsertAnalysisStep inserting the analysis step].