Resource: name_conv
Resource | name_conv |
Command Line | -nc=name_conv |
Environment Variable | wxpnameconv |
Default Value | name_conv file |
The name convention file defines how most data files are accessed by WXP. The name convention file essentially allows the user to specify any naming convention.
This is a critical file as WXP may not work properly without this file existing and set up properly. This resource specifies the name of this file. By default, it expects a file named "name_conv" in the file_path directory. This file has a standard set of naming conventions using the ymdh_t naming convention. WXP comes with some preset name convention files to roughly match the name convention setup of older versions of WXP:
- hmdy - the standard hour, month, day, year naming convention
- ymdh - the more practical year, month, day, hour naming convention
- ymdh_t - the special Unidata naming convention adopted in WXP 4.7.
Often, this sample is copied into the "name_conv" file but you can list the specific name convention if you system uses more than one.
Naming Convention File
The file name convention file ties the file paths to the actual data files. The name convention also tags data files for date and data type, making it easier for WXP programs to find data files that are current or for any specific time.
Each line in the data file contains a specific file name convention for a particular type of data. The line contains a name convention tag followed by the name convention string.
tag convention_string
The tag is important as most WXP programs use specific tags to find specific name conventions. The tag itself has two parts: a data type followed by a file type. For example, surface data saved by the LDM into the LDM data tree would have a tag of sfc_dat. Upper air data would be upa_dat. In general all LDM data has the _dat suffix. All surface data has a sfc prefix.
Tag Prefix | Data Type |
sfc | Surface Data |
syn | Synoptic Data |
upa | Upper Air Data |
rad | MDR Radar Data |
mos | MOS Data |
sat | Satellite Data |
grib | Model GRIB Data |
Tag Suffix | File Type |
dat | LDM Ingested Data |
cvt | WXP Decoded Data |
raw | WXP Raw Files |
grd | WXP Grid Files |
par | WXP Parsed Files |
The name convention string is generally a combination of the file path and a name convention based on date and file type. The string uses a wildcard substitution system much like shell scripts use variable substitution. Anything not part of a wildcard is taken literally. Here is a list of the wildcards:
Wildcards | Description |
PATHS |
|
%F | file_path resource |
%D | data_path resource |
%C | con_path resource |
%G | grid_path resource |
%R | raw_path resource |
%I | image_path resource |
%W | watch_path resource |
DATE |
|
%Y | Current year (1900-) |
%y | Current year (00-99) |
%B | Current month (JAN-DEC) |
%b | Current month (jan-dec) |
%m | Current month (01-12) |
%j | Current julian day (0-365) |
%d | Current day (01-31) |
%h | Current hour (00-23) |
%n | Current minute (00-59) |
PRESET VALUES |
|
%r | region |
%l | vertical level |
%f | forecast time |
%v | variable |
%x | model |
%p | program name |
%i | loop/frame index |
%e | tag extension |
Most WXP program will read in one file type and create another as output. For example, the surface decoder reads in a file with the sfc_dat convention and produces a decoded file with the sfc_cvt convention. These tags can be changed with the in_file and out_file resources.
The following is a sample of the name convention file::
sfc_dat %D/%y%m%d%h_sao.wmo sfc_cvt %C/%y%m%d%h_sao.wxp sfc_raw %R/%v_%m%d%h_sfc.raw sfc_grd %G/%v_%m%d%h_sfc.grd rad_dat %D/%y%m%d%h_rad.wmo rad_cvt %C/%y%m%d%h_rad.wxp upa_dat %D/%y%m%d%h_upa.wmo upa_cvt %C/%y%m%d%h_upa.wxp upa_raw %R/%l_%v_%m%d%h_upa.raw upa_grd %G/%l_%v_%m%d%h_upa.grd mos_dat %D/%y%m%d%h_mod.wmo mos_raw %R/%f_%v_%m%d%h_mod.raw mos_grd %G/%f_%v_%m%d%h_mod.grd frt_dat %D/%y%m%d%h_frt.wmo wws_raw %W/%y%m%d%h_wws.wmo
As you can see, the surface SAO files will be located in the data_path directory (%D=/home/wxp/ddplus) and with a name convention of year, month, day, hour and a type extension of sao.wmo.
The user may also specify the frequency of files. For example, you could specify %5n which says the data comes in every 5 minutes. This makes determining the current file much easier. With the name convention syntax, you should be able to handle most if not every combination of file names. You can change name convention files by changing the name_conv resource if needed.
Last updated July 30, 1998