Changes between Version 19 and Version 20 of OMI_observation_modules

Timestamp:

Nov 28, 2020, 9:57:39 AM (4 years ago)

Author:

lnerger

Comment:

--

OMI_observation_modules

@@ -89 +89 @@
 `thisobs%doassim`. 
 
-The main steps performed in this routine are
- 1. `thisobs%doassim`: Specify whether this observation type is assimilated
- 1. `thisobs%disttype`: Specify the type of distance computation
- 1. `thisobs%ncoord`: Specify the number of dimensions used to compute distances 
- 1. `dim_obs_p`: Count the number of available observations
- 1. `obs_p`: Fill the vector of observations
- 1. `ocoord_p`: store the coordinates of the observations
- 1. `ivar_obs_p`: store the inverse error variance of each observation
- 1. `thisobs%id_obs_p`: store the indices of state vector elements that correspond to an observation (A single value for observation at grid points, or multiple values for derived quantities or interpolation)
-
-When the observation operator performs interpolation, one further needs to initialize an array of interpolation coefficients (`thisobs%icoeff_p`). For Cartesian distance computation with periodicity one also needs to set `thisobs%domainsize`.
+The main variables that the filled in this routine are
+ 1. [wiki:OMI_observation_modules#thisobsdoassim thisobs%doassim]: Specify whether this observation type is assimilated
+ 1. [wiki:OMI_observation_modules#thisobsdisttype thisobs%disttype]: Specify the type of distance computation
+ 1. [wiki:OMI_observation_modules#thisobsncoord thisobs%ncoord]: Specify the number of dimensions used to compute distances 
+ 1. [wiki:OMI_observation_modules#dim_obs_p dim_obs_p]: Count the number of available observations
+ 1. [wiki:OMI_observation_modules#obs_p obs_p]: Fill the vector of observations
+ 1. [wiki:OMI_observation_modules#ocoord_p ocoord_p]: store the coordinates of the observations
+ 1. [wiki:OMI_observation_modules#ivar_obs_p ivar_obs_p]: store the inverse error variance of each observation
+ 1. [wiki:OMI_observation_modules#thisobsid_obs_p thisobs%id_obs_p]: store the indices of state vector elements that correspond to an observation (A single value for observation at grid points, or multiple values for derived quantities or interpolation)
+
+When the observation operator performs interpolation, one further needs to initialize an array of interpolation coefficients ([wiki:OMI_observation_modules#thisobsicoeff_p thisobs%icoeff_p]). For Cartesian distance computation with periodicity one also needs to set [wiki:OMI_observation_modules#thisobsdomainsize thisobs%domainsize].
 
 When parallel model with domain decomposition is used, the variables with suffix `_p` need to describe the observation information for a particular process domain. The following routine will perform the necessary operations to ensure that the parallelization is taken into account by PDAF.
@@ -207 +207 @@
 See `/models/lorenz96_omi/` for an example using case 1 with periodicity in one dimension.
 
-=== `thisobs%domainsize` ===
-
-This array has to be allocated as
-{{{
-   ALLOCATE(thisobs%domainsize(thisobs%ncoord))
-}}}
-Here one has to specify the size of the domain in each of its thisobs%ncoord dimensions. The information is used to compute the Cartesian distance with periodicity.
-
-Setting one dimension to 0 or a negative value indicates that there is no periodicity in this direction. 
+
+=== `dim_obs_p` ===
+
+This is a single integer value giving the number of observations. With a parallel model using domain-decomposition this will be the number of observations  for the process sub-domain. For observation files holding all observations one can read these and then check which observation redice within the process sub-domain. `dim_obs_p` will be used to allocate further arrays and as input argument to `PDAFomi_gather_obs`.
+
+=== `obs_p` ===
+
+This should be a vector of real values. It will be used as an argument to `PDAFomi_gather_obs`. The order of the entries has to be consistent in the arrays `thisobs%id_obs_p`, `obs_p`, `ivar_obs_p`, and `ocoord_p`.
+
+
+=== `ocoord_p` ===
+
+This should be a rank-2 array of real values with size (thisobs%ncoord, dim_obs_p). It will be used as an argument to `PDAFomi_gather_obs`. The order of the entries has to be consistent in the arrays `thisobs%id_obs_p`, `obs_p`, `ivar_obs_p`, and `ocoord_p`.
+
+The coordinates of the observation with index `k` are given by `ocoord_p(:,k)`. 
+
+
+=== `ivar_obs_p` ===
+
+This should be a vector of real values. It will be used as an argument to `PDAFomi_gather_obs`. The order of the entries has to be consistent in the arrays `thisobs%id_obs_p`, `obs_p`, `ivar_obs_p`, and `ocoord_p`.
 
 
@@ -234 +245 @@
 
 
+=== `thisobs%domainsize` ===
+
+This array has to be allocated as
+{{{
+   ALLOCATE(thisobs%domainsize(thisobs%ncoord))
+}}}
+Here one has to specify the size of the domain in each of its thisobs%ncoord dimensions. The information is used to compute the Cartesian distance with periodicity.
+
+Setting one dimension to 0 or a negative value indicates that there is no periodicity in this direction. 
+
+
 === `thisobs%icoeff_p` ===