Changes between Initial Version and Version 1 of PDAF_gather_obs_f2

Timestamp:

Dec 20, 2017, 5:35:42 PM (6 years ago)

Author:

lnerger

Comment:

--

PDAF_gather_obs_f2

@@ +1 @@
+= PDAF_gather_obs_f2 = 
+
+This page documents the routine `PDAF_gather_obs_f2` of PDAF, which was introduced with PDAF V1.13.
+
+In the local filters (LESKTF, LETKF, LSEIK, LNETF) this routine gathers the process-local observation coordinates arrays and returns the cooridates for the full observation vector.
+
+The routine depends on `PDAF_gather_dim_obs_f` which defines the process-local observation dimensions. Further, the related routine `PDAF_gather_obs_f` is used to collect the full state vector.
+
+The routine is typically used in the routines `init_dim_obs_f_pdaf` if the analysis step of the local filters is parallelized.
+
+The interface is the following:
+{{{
+  SUBROUTINE PDAF_gather_obs_f2(coords_obs_p, coords_obs_f, nrows, status)
+}}}
+with the following arguments:
+ * `coords_obs_p` : `real, intent(in)`[[BR]] Process-local observation coordinates array
+ * `coords_obs_f` : `real, intent(out)`[[BR]] Full observation coordinates array
+ * `nrows` : `integer, intent(in)`[[BR]] Number of rows in observation coordinates array
+ * `status` : `integer, intent(out)`[[BR]] Status flag (0 for no error)
+
+Notes:
+ * The routine `PDAF_gather_dim_obs_f` has to be called once before using `PDAF_gather_obs_f` because it internally initializes the local observation dimensions for gathering. The most recent call to `PDAF_gather_dim_obs_f` defines the dimensions used here.
+ * The routine is used for a coordinate array which stores in each column the coordinates of one observation. Thus for a two-dimensional case, the size of `coords_obs_p` is `(2, dim_obs_p)` and `nrows=2` is used in the call to `PDAF_gather_obs_f2`.
+ * If the coordindates are stored so that each row of `coords_obs_p` holds the coordinates of one observation the routine `PDAF_gather_obs_f` should be applied separate for each column to gather the full coordinates array.