Changes between Initial Version and Version 1 of U_localize

Timestamp:

Dec 2, 2016, 11:31:01 AM (8 years ago)

Author:

lnerger

Comment:

--

U_localize

@@ +1 @@
+= U_localize =
+
+The page document the user-supplied call-back routine `U_localize`.
+
+The routine `U_localize` is a call-back routine that has to be provided by the user. In the simplified interface the predefined name of the routine is `localize_enkf_pdaf`, but in the full interface, the user can choose the name of the routine.
+The routine is used with the localized EnKF and called during the analysis step. The purpose of the routine is to apply covariance localization to the matrices '''HP''' and '''HPH^T^''', which are provided as input/output arguments.
+
+The interface is the following:
+{{{
+SUBROUTINE U_localize(dim_p, dim_obs, HP, HPH)
+}}}
+with
+ * `dim` : `integer, intent(in)`[[BR]] State dimension
+ * `dim_obs` : `integer, intent(in)`[[BR]] Number of observations at current time step (i.e. the size of the observation vector)
+ * `HP` : `real, intent(in), dimension(dim_obs, dim_p)`[[BR]] Matrix HP
+ * `HPH` : `real, intent(in), dimension(dim_obs, dim_obs)`[[BR]] Matrix HPH^T
+
+
+Notes:
+ * In case of a parallelization with domain decomposition, `HP` contains only the columns of the matrix that resides on the model sub-domain of the calling process. The number of rows is that of the global number of observations
+
+Hints:
+ * To compute the localization one can use the routine `PDAF_local_weight` after computing the distance between two elements in the matrix '''HP''' or '''HPH^T^'''.