Changes between Initial Version and Version 1 of U_localize_covar_serial

Timestamp:

Mar 23, 2025, 9:14:59 AM (10 days ago)

Author:

lnerger

Comment:

--

U_localize_covar_serial

@@ +1 @@
+= U_localize_covar_serial =
+
+The page document the user-supplied call-back routine `U_localize_covar_serial`, which was introduced with PDAF V3.0.
+
+The routine `U_localize_covar_serial` is a call-back routine that has to be provided by the user. The typical name in the user codee is `localize_covar_pdaf`, but the user can choose the name of the routine.
+The routine is used in the ENSRF/EAKF and is called during the analysis step. The purpose of the routine is to apply covariance localization to the vectors '''Hi P''' and '''Hi PH^T''' for the assimilation of a single observation (determined by the observation operator '''Hi'''). Here '''Hi PH^T''' is for the vector relating to the observed covariance matrix for the full observation vector, which is reuired for parallelization
+
+The interface is the following:
+{{{
+  SUBROUTINE U_localize_covar_serial(iobs, dim_p, dim_obs, HP_p, HXY_p)
+}}}
+with arguments:
+{{{
+  INTEGER, INTENT(in) :: iobs                  !< Index of the assimilated single observation
+  INTEGER, INTENT(in) :: dim_p                 !< Process-local state dimension
+  INTEGER, INTENT(in) :: dim_obs_f             !< Number of full observations
+  REAL, INTENT(inout) :: HP_p(dim_p)           !< Process-local part of matrix HP for observation iobs
+  REAL, INTENT(inout) :: HXY_p(dim_obs_F)      !< Process-local part of matrix HX(HX_all) for full observations
+}}}
+
+Hints:
+ * To compute the localization one can use the routine `PDAF_local_weight` after computing the distance between two elements in the vector '''Hi P''' or '''Hi PH^T'''.