Computes the weight with which an observation should impact a state variable that is separated by a given distance. The distance is in units determined by the location module being used.
This namelist is read from the file input.nml
. Namelists start with an ampersand '&' and terminate with a slash '/'.
Character strings that contain a '/' must be enclosed in quotes to prevent them from prematurely terminating the
namelist.
&cov_cutoff_nml select_localization = 1 /
Item | Type | Description |
---|---|---|
select_localization | integer | Selects the localization function.
|
types_mod utilities_mod location_mod
use cov_factor_mod, only : | comp_cov_factor |
A note about documentation style. Optional arguments are enclosed in brackets [like this].
var = comp_cov_factor(z_in, c [, obs_loc] [, obs_type] [, target_loc] [, target_kind] [, localization_override])
real(r8) :: comp_cov_factor real(r8), intent(in) :: z_in real(r8), intent(in) :: c type(location_type), optional, intent(in) :: obs_loc integer, optional, intent(in) :: obs_type type(location_type), optional, intent(in) :: target_loc integer, optional, intent(in) :: target_kind integer, optional, intent(in) :: localization_override
Returns a weighting factor for observation and a target variable (state or observation) separated by distance z_in and with a half-width distance, c. Three options are provided and controlled by a namelist parameter. The optional argument localization_override controls the type of localization function if present. The optional arguments obs_loc, obs_type and target_loc, target_kind are not used in the default code. They are made available for users who may want to design more sophisticated localization functions.
var |
Weighting factor. |
z_in |
The distance between observation and target. |
c |
Factor that describes localization function. Describes half-width of functions used here. |
obs_loc | Location of the observation. |
obs_type | Observation specific type. |
target_loc | Location of target. |
target_kind | Generic kind of target. |
localization_override | Controls localization type if present. Same values as for namelist control. |
filename | purpose |
---|---|
input.nml | to read cov_cutoff_nml |
- Gaspari and Cohn, 1999, QJRMS, 125, 723-757. (eqn. 4.10)
Routine | Message | Comment |
---|---|---|
comp_cov_factor | Illegal value of "select_localization" in cov_cutoff_mod namelist | Only values 1 through 3 select a localization function. |
N/A