PDAF_iau_set_state_pointer

This page documents the routine PDAF_iau_set_state_pointer of PDAF, which was introduced with the final release of PDAF V3.0.

With this routine the user can set a pointer to the PDAF-internal array of the state vector increment used in the Ensemble OI modes (subtype 10 and 11). This gives direct access to the increment vector e.g. to analyze it or to write it into a file for restarting.

The routine can be called by each single process, but it only provides a pointer to the process-local part of the increment array. For domain-decomposed models, this array only includes the state vector part for the process domain. In addition, it usually only contains a sub-ensemble unless one uses the flexible parallelization mode with a single model task. For the fully parallel mode, the process(es) of a single model task only hold a single ensemble state.

The interface is:

  SUBROUTINE PDAF_iau_set_pointer(iau_state_ptr, flag)

    REAL, POINTER, INTENT(out) :: iau_state_ptr(:)    ! Pointer to IAU state vector
    INTEGER, INTENT(out)       :: flag                ! Status flag

Hints:

• In Fortran user code one has to declare
  REAL, POINTER :: iau_state_ptr(:)
  and provide this as the first argument. One does not need to allocate this pointer.