Note
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5.1.14.3. PCPCombine: User-defined Command Use Case
met_tool_wrapper/PCPCombine/PCPCombine_user_defined.conf
Scientific Objective
Derive statistics (sum, minimum, maximum, range, mean, standard deviation, and valid count) using six 3 hour precipitation accumulation fields. This use case builds the same command as pcp_derive.conf, but the command is defined completely by the user in the METplus configuration file.
Datasets
METplus Components
This use case utilizes the METplus PCPCombine wrapper to generate a command to run PCPCombine to derive statistics from the fields. FCST_PCP_COMBINE_COMMAND is used to define all arguments to the call to the MET tool pcp_combine. This variable uses filename template notation using the ‘shift’ keyword to define filenames that are valid at a time slightly shifted from the run time, i.e. wrfprs_ruc13_{lead?fmt=%HH?shift=-3H}.tm00_G212. It also references other configuration variables in the METplus configuration file, such as FCST_PCP_COMBINE_INPUT_NAMES and FCST_PCP_COMBINE_INPUT_LEVELS, and FCST_PCP_COMBINE_INPUT_DIR.
METplus Workflow
PCPCombine is the only tool called in this example. It processes the following run times:
METplus Configuration
METplus first loads all of the configuration files found in parm/metplus_config, then it loads any configuration files passed to METplus via the command line with the -c option, i.e. -c parm/use_cases/met_tool_wrapper/PCPCombine/PCPCombine_user_defined.conf
# PCPCombine Subtract Method Example
[config]
# List of applications to run - only PCPCombine for this case
PROCESS_LIST = PCPCombine
# time looping - options are INIT, VALID, RETRO, and REALTIME
# If set to INIT or RETRO:
# INIT_TIME_FMT, INIT_BEG, INIT_END, and INIT_INCREMENT must also be set
# If set to VALID or REALTIME:
# VALID_TIME_FMT, VALID_BEG, VALID_END, and VALID_INCREMENT must also be set
LOOP_BY = INIT
# Format of INIT_BEG and INT_END using % items
# %Y = 4 digit year, %m = 2 digit month, %d = 2 digit day, etc.
# see www.strftime.org for more information
# %Y%m%d%H expands to YYYYMMDDHH
INIT_TIME_FMT = %Y%m%d%H
# Start time for METplus run - must match INIT_TIME_FMT
INIT_BEG = 2005080700
# End time for METplus run - must match INIT_TIME_FMT
INIT_END = 2005080700
# Increment between METplus runs (in seconds if no units are specified)
# Must be >= 60 seconds
INIT_INCREMENT = 1M
# List of forecast leads to process for each run time (init or valid)
# In hours if units are not specified
# If unset, defaults to 0 (don't loop through forecast leads)
LEAD_SEQ = 24H
# Order of loops to process data - Options are times, processes
# Not relevant if only one item is in the PROCESS_LIST
# times = run all wrappers in the PROCESS_LIST for a single run time, then
# increment the run time and run all wrappers again until all times have
# been evaluated.
# processes = run the first wrapper in the PROCESS_LIST for all times
# specified, then repeat for the next item in the PROCESS_LIST until all
# wrappers have been run
LOOP_ORDER = times
# verbosity of PCPCombine MET output
#LOG_PCP_COMBINE_VERBOSITY = 2
# If True, run pcp_combine on forecast data
# observation equivalent OBS_PCP_COMBINE_RUN also exists
FCST_PCP_COMBINE_RUN = True
# mode of pcp_combine to use (SUM, ADD, SUBTRACT, DERIVE, or USER_DEFINED)
FCST_PCP_COMBINE_METHOD = USER_DEFINED
# user-defined command to run pcp_combine
# NOTE: do not include pcp_combine app name or the output path, these will be added in automatically
FCST_PCP_COMBINE_COMMAND = -derive sum,min,max,range,mean,stdev,vld_count {FCST_PCP_COMBINE_INPUT_DIR}/{init?fmt=%Y%m%d%H}/wrfprs_ruc13_{lead?fmt=%HH}.tm00_G212 {FCST_PCP_COMBINE_INPUT_DIR}/{init?fmt=%Y%m%d%H}/wrfprs_ruc13_{lead?fmt=%HH?shift=-3H}.tm00_G212 {FCST_PCP_COMBINE_INPUT_DIR}/{init?fmt=%Y%m%d%H}/wrfprs_ruc13_{lead?fmt=%HH?shift=-6H}.tm00_G212 {FCST_PCP_COMBINE_INPUT_DIR}/{init?fmt=%Y%m%d%H}/wrfprs_ruc13_{lead?fmt=%HH?shift=-9H}.tm00_G212 {FCST_PCP_COMBINE_INPUT_DIR}/{init?fmt=%Y%m%d%H}/wrfprs_ruc13_{lead?fmt=%HH?shift=-12H}.tm00_G212 {FCST_PCP_COMBINE_INPUT_DIR}/{init?fmt=%Y%m%d%H}/wrfprs_ruc13_{lead?fmt=%HH?shift=-15H}.tm00_G212 -field 'name="{FCST_PCP_COMBINE_INPUT_NAMES}"; level="{FCST_PCP_COMBINE_INPUT_LEVELS}";'
# description of data to be processed
# used in output file path
MODEL = GFS
# Forecast data description variables
# set to True if forecast input is probabilistic
FCST_IS_PROB = false
# Input data type of forecast input, only used if data is probabilistic to determine
# how to extract data from file
FCST_PCP_COMBINE_INPUT_DATATYPE = GRIB
# List of input accumulations for forecast data. Units are hours if not specified
# Items should be in order of preference of what accumulations to use if available and relevant
# Each item in the list corresponds to the equivalent in *_INPUT_NAMES and *_INPUT_LEVELS if specified
FCST_PCP_COMBINE_INPUT_ACCUMS = 3H
# List of input names corresponding to each accumulation in *_INPUT_ACCUMS
# Can be left blank if using GRIB input
FCST_PCP_COMBINE_INPUT_NAMES = APCP
# List of input levels corresponding to each accumulation in *_INPUT_ACCUMS
# Can be left blank if using GRIB input
FCST_PCP_COMBINE_INPUT_LEVELS = A03
# desired output accumulation to build with forecast input
# Units are in hours if not specified
FCST_PCP_COMBINE_OUTPUT_ACCUM = A24
# End of [config] section and start of [dir] section
[dir]
# input and output data directories
FCST_PCP_COMBINE_INPUT_DIR = {INPUT_BASE}/met_test/data/sample_fcst
FCST_PCP_COMBINE_OUTPUT_DIR = {OUTPUT_BASE}/met_tool_wrapper/PCPCombine/PCPCombine_user_defined
# End of [dir] section and start of [filename_templates] section
[filename_templates]
# format of filenames
FCST_PCP_COMBINE_INPUT_TEMPLATE = {init?fmt=%Y%m%d%H}/wrfprs_ruc13_{lead?fmt=%HH}.tm00_G212
FCST_PCP_COMBINE_OUTPUT_TEMPLATE = wrfprs_ruc13_{init?fmt=%Y%m%d%H}_f{lead?fmt=%HH}_A{level?fmt=%HH}.nc
MET Configuration
None. PCPCombine does not use configuration files.
Running METplus
This use case can be run two ways:
Passing in PCPCombine_user_defined.conf then a user-specific system configuration file:
run_metplus.py -c /path/to/METplus/parm/use_cases/met_tool_wrapper/PCPCombine/PCPCombine_user_defined.conf -c /path/to/user_system.conf
Modifying the configurations in parm/metplus_config, then passing in PCPCombine_user_defined.conf:
run_metplus.py -c /path/to/METplus/parm/use_cases/met_tool_wrapper/PCPCombine/PCPCombine_user_defined.conf
The former method is recommended. Whether you add them to a user-specific configuration file or modify the metplus_config files, the following variables must be set correctly:
INPUT_BASE - Path to directory where sample data tarballs are unpacked (See Datasets section to obtain tarballs). This is not required to run METplus, but it is required to run the examples in parm/use_cases
OUTPUT_BASE - Path where METplus output will be written. This must be in a location where you have write permissions
MET_INSTALL_DIR - Path to location where MET is installed locally
Example User Configuration File:
[dir]
INPUT_BASE = /path/to/sample/input/data
OUTPUT_BASE = /path/to/output/dir
MET_INSTALL_DIR = /path/to/met-X.Y
NOTE: All of these items must be found under the [dir] section.
Expected Output
A successful run will output the following both to the screen and to the logfile:
INFO: METplus has successfully finished running.
Refer to the value set for OUTPUT_BASE to find where the output data was generated. Output for this use case will be found in met_tool_wrapper/PCPCombine/PCPCombine_user_defined (relative to OUTPUT_BASE) and will contain the following files:
wrfprs_ruc13_2005080700_f24_A24.nc
Keywords
sphinx_gallery_thumbnail_path = ‘_static/met_tool_wrapper-PCPCombine.png’
Total running time of the script: ( 0 minutes 0.000 seconds)