Changes between Version 8 and Version 9 of OMI_Callback_obs_pdafomi

Timestamp:

Nov 22, 2020, 10:16:18 AM (4 years ago)

Author:

lnerger

Comment:

--

OMI_Callback_obs_pdafomi

@@ -5 +5 @@
 The file `callback_obs_pdafomi.F90` contains are those routines that are directly called by PDAF as call-back routines. In the example codes we use all routines with the suffix _pdafomi to distinguish them from routine from existing implementation where the suffix is typically _pdaf. 
 
-The file `templates/omi/callback_obs_pdafomi.F90` provides a template for implementing the routines. A compact example canbe found in `tutorial/online_2D_serialmodel_omi/`.
+The file `templates/omi/callback_obs_pdafomi.F90` provides a template for implementing the routines. A compact example can be found in `tutorial/online_2D_serialmodel_omi/`.
 
-As mentioned in the OMI introduction, the routines are mainly pass-through routines. Thus, one typically includes the observation-specific routine with ‘use’ and then calls this routine. However, the is small additional functionality in the different routines which has to be handles when implementing the routine or adding an observation type
+The routines are mainly pass-through routines. Thus, one typically includes the observation-specific routine with ‘use’ and then calls this routine. However, there is small additional functionality in the different routines which has to be handled when implementing the routine or adding an observation type.
+
+In the descriptions below we use 'TYPE' as a generic label for an observation type. When implemeting an observation type, one replace this by an actual name. For example for sea surface temperature (sst) observations, one could replace TYPE by 'sst' and write e.g. `init_dim_obs_sst`.
 
 == init_dim_obs_pdafomi ==
 
-  In this routine we declare a dimension variable `dim_obs_TYPE` for each observation type. This is initialized by the corresponding routine `init_dim_obs_TYPE`. The sum of these individual dimension yields the total number of observations, which is returned to PDAF. 
+  In this routine we declare a dimension variable `dim_obs_TYPE` for each observation type. This is initialized by the corresponding routine `init_dim_obs_TYPE`. The sum of these individual dimensions yields the total number of observations, which is returned to PDAF. 
 
 The implementation steps are:
@@ -19 +21 @@
 1. add `dim_obs_TYPE` to the final sum computing `dim_obs`.
 
+As an example, in `tutorial/online_2D_serialmodel_omi/` we have three observations, named A, B, and C. In `init_dim_obs_pdafomi` we find the lines
+{{{
+  USE obs_A_pdafomi, ONLY: assim_A, init_dim_obs_A
+  USE obs_B_pdafomi, ONLY: assim_B, init_dim_obs_B
+  USE obs_C_pdafomi, ONLY: assim_C, init_dim_obs_C
+
+  INTEGER :: dim_obs_A ! Observation dimensions
+  INTEGER :: dim_obs_B ! Observation dimensions
+  INTEGER :: dim_obs_C ! Observation dimensions
+
+  dim_obs_A = 0
+  dim_obs_B = 0
+  dim_obs_C = 0
+
+  IF (assim_A) CALL init_dim_obs_A(step, dim_obs_A)
+  IF (assim_B) CALL init_dim_obs_B(step, dim_obs_B)
+  IF (assim_C) CALL init_dim_obs_C(step, dim_obs_C)
+}}}
+
+
 Notes:
- - The variable `assim_TYPE` indicates whether a particular observation type is assimilated. It is usually defined in init_pdaf, or by reading from the command line or a namelist file.
- - The observation-module can have either a specific name for `init_dim_obs_TYPE` or a generic name. If the generic name `init_dim_obs` is used one can apply a name conversion `init_dim_obs_TYPE => init_dim_obs`. 
+ - The variable `assim_TYPE` indicates whether a particular observation type is assimilated. It is usually set in `init_pdaf`, or by reading from the command line or a namelist file.
+ - The obs-module can have either a specific name for `init_dim_obs_TYPE` or a generic name. If the generic name `init_dim_obs` is used one can apply a name conversion `init_dim_obs_TYPE => init_dim_obs`. 
 
 
@@ -31 +53 @@
 The implementation steps are:
 1. Include the observation-specific routine `obs_op_TYPE` from the observation-module with 'use'
-1. Add a call to the observation-specific routine obs_op_TYPE
+1. Add a call to the observation-specific routine `obs_op_TYPEz
+
+As an example, in `tutorial/online_2D_serialmodel_omi/` we have
+{{{
+  USE obs_A_pdafomi, ONLY: obs_op_A
+  USE obs_B_pdafomi, ONLY: obs_op_B
+  USE obs_C_pdafomi, ONLY: obs_op_C
+
+  CALL obs_op_A(dim_p, dim_obs, state_p, ostate)
+  CALL obs_op_B(dim_p, dim_obs, state_p, ostate)
+  CALL obs_op_C(dim_p, dim_obs, state_p, ostate)
+}}}
 
 Notes:
- - The order of the calls to `obs_op_TYPE` is not relevant because the setup of the overall full observation vector is defined by the order of the calls in init_dim_obs_pdafomi. Anyway, it's good practive to keep the order of the calls consistent.
+ - The order of the calls to `obs_op_TYPE` is not relevant because the setup of the overall full observation vector is defined by the order of the calls in init_dim_obs_pdafomi. Anyway, it's good practice to keep the order of the calls consistent.
+ - We don't need an IF-statement with `assim_TYPE` here. The check is done within each obs-module.
 
 
@@ -45 +79 @@
 1. Add a call to the observation-specific routine init_dim_obs_l_TYPE
 
+As an example, in `tutorial/online_2D_serialmodel_omi/` we have
+{{{
+  USE obs_A_pdafomi, ONLY: init_dim_obs_l_A
+  USE obs_B_pdafomi, ONLY: init_dim_obs_l_B
+  USE obs_C_pdafomi, ONLY: init_dim_obs_l_C
+
+  CALL init_dim_obs_l_A(domain_p, step, dim_obs, dim_obs_l)
+  CALL init_dim_obs_l_B(domain_p, step, dim_obs, dim_obs_l)
+  CALL init_dim_obs_l_C(domain_p, step, dim_obs, dim_obs_l)
+}}}
+
+Notes:
+ - The order of the calls to `init_dim_obs_l_TYPE` defines the order in which the observations are stored in the local observation vector. The calling order does not need to be the same as in the other routines, but it's good practive to keep the order of the calls consistent.
 
 == localize_covar_pdafomi ==
@@ -55 +102 @@
 1. Add a call to the observation-specific routine localize_covar_TYPE
 
+As an example, in `tutorial/online_2D_serialmodel_omi/` we have
+{{{
+  USE obs_A_pdafomi, ONLY: localize_covar_A
+  USE obs_B_pdafomi, ONLY: localize_covar_B
+  USE obs_C_pdafomi, ONLY: localize_covar_C
+
+  REAL, ALLOCATABLE :: coords_p(:,:) ! Coordinates of PE-local state vector entries
+
+  ALLOCATE(coords_p(2, dim_p))
+  coords_p = ...                     ! Initialize coords_p
+
+
+  CALL localize_covar_A(dim_p, dim_obs, HP_p, HPH, coords_p)
+  CALL localize_covar_B(dim_p, dim_obs, HP_p, HPH, coords_p)
+  CALL localize_covar_C(dim_p, dim_obs, HP_p, HPH, coords_p)
+
+  DEALLOCATE(coords_p)
+}}}
+
+Notes:
+ - Instead of allocating and filling the coordinate array `coords_p` in this routine one could also do it once in `init_pdaf` and declare the array in the module `mod_assimilation`.
+ - The order of the calls to `obs_op_TYPE` is not relevant because the setup of the overall full observation vector is defined by the order of the calls in init_dim_obs_pdafomi. Anyway, it's good practice to keep the order of the calls consistent.
 
 == deallocate_obs_pdafomi == 
@@ -64 +133 @@
 1. add a call to `PDAFomi_deallocate_obs` giving the observation-specific `obs_TYPE` as argument.
 1. To perform the deallocation, insert a call to deallocate_obs_pdafomi at the end of the routine `prepoststep_pdaf`.
+
+As an example, in `tutorial/online_2D_serialmodel_omi/` we have
+{{{
+  USE PDAFomi, ONLY: PDAFomi_deallocate_obs
+  USE obs_A_pdafomi, ONLY: obs_A => thisobs
+  USE obs_B_pdafomi, ONLY: obs_B => thisobs
+  USE obs_C_pdafomi, ONLY: obs_C => thisobs
+
+  CALL PDAFomi_deallocate_obs(obs_A)
+  CALL PDAFomi_deallocate_obs(obs_B)
+  CALL PDAFomi_deallocate_obs(obs_C)
+}}}