Changes between Initial Version and Version 1 of PDAFomi_diag_get_obs

Timestamp:

Mar 23, 2025, 8:25:08 AM (11 days ago)

Author:

lnerger

Comment:

--

PDAFomi_diag_get_obs

@@ +1 @@
+= PDAFomi_diag_get_obs = 
+
+This page documents the routine `PDAFomi_diag_get_obs` of PDAF, which was introduced with PDAF V3.0. This is part of the PDAF-OMI observation diagnostics module. 
+
+The routine returns a pointer to a vector of observations of the specified observation type (`id_obs`) and a pointer to the corresponding array of observation coordinates.
+
+Usually all PDAFomi_diag routines are called in `prepoststep_pdaf` where the observation information can be retrieved and analyzed.
+
+The interface is the following: 
+{{{
+  SUBROUTINE PDAFomi_diag_get_obs(id_obs, dim_obs_diag, ncoord, obs_p_ptr, ocoord_p_ptr)
+}}}
+with the following arguments:
+{{{
+    INTEGER, INTENT(in) :: id_obs                    ! Index of observation type to return
+    INTEGER, INTENT(out) :: dim_obs_diag             ! Observation dimension
+    INTEGER, INTENT(out) :: ncoord                   ! Number of observation dimensions
+    REAL, POINTER, INTENT(out) :: obs_p_ptr(:)       ! Pointer to observation vector
+    REAL, POINTER, INTENT(out) :: ocoord_p_ptr(:,:)  ! Pointer to coordinate array
+                                                     ! (index order as in observation modules)
+}}}
+
+**Notes:**
+ * In Fortran user code the obsevation pointer should be declared in the form[[BR]] `REAL, POINTER :: obs_p_ptr(:)`[[BR]] It does not need to be allocated
+ * In Fortran user code the obsevation pointer should be declared in the form[[BR]] `REAL, POINTER :: ocoord_p_ptr(:,:)`[[BR]] It does not need to be allocated
+ * If the observation diagnostics have not be activated by using [wiki:PDAFomi_set_obs_diag] the pointers will not be set and `dim_obs_diag=0` and `ncoord=0` will be returned. These values canbe checked before assessing the pinter arrays
+ * The array `ocoord_p_ptr(:,:)` is organized as in the observation modules:
+   * First index: index of different coordinate directions for observation specified by the second index
+   * Second index: ID of the observation
+
+