5.1.18.2. PyEmbedIngest: Basic Use Case

met_tool_wrapper/PyEmbedIngest/PyEmbedIngest.conf

Scientific Objective

None. Simply converting file formats so data can be read by the MET tools.

Datasets

Inputs: Canned ASCII data to test functionality

Location: All of the input data required for this use case can be found in the met_test sample data tarball. Click here to the METplus releases page and download sample data for the appropriate release: https://github.com/dtcenter/METplus/releases

This tarball should be unpacked into the directory that you will set the value of INPUT_BASE. See Running METplus section for more information.

METplus Components

This use case utilizes the METplus PyEmbedIngest wrapper to generate a command to run the MET tool RegridDataPlane if all required files are found.

METplus Workflow

PyEmbedIngest is the only tool called in this example. It has one run time, but the time is not relevant because the files processed do not have any time information in the names.

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/PyEmbedIngest/PyEmbedIngest.conf

# PyEmbedIngest wrapper example

[config]
# Options are times, processes
# times = run all items in the PROCESS_LIST for a single initialization
# time, then repeat until all times have been evaluated.
# processes = run each item in the PROCESS_LIST for all times
#   specified, then repeat for the next item in the PROCESS_LIST.
LOOP_ORDER = times

# time looping - options are INIT, VALID, RETRO, and REALTIME
LOOP_BY = VALID

# Format of VALID_BEG and VALID_END
VALID_TIME_FMT = %Y%m%d%H

# Start time for METplus run
VALID_BEG = 2013022712

# End time for METplus run
VALID_END = 2013022712

# Increment between METplus runs in seconds. Must be >= 60
VALID_INCREMENT = 21600

# list of forecast leads to process
LEAD_SEQ = 0

# List of applications to run
PROCESS_LIST = PyEmbedIngest


# 1st INGEST INSTANCE
# python script with optional arguments to run for 1st ingest instance
PY_EMBED_INGEST_1_SCRIPT = {INPUT_BASE}/met_test/scripts/python/read_ascii_numpy.py {INPUT_BASE}/met_test/data/python/obs.txt OBS

# type of python input to expect for 1st ingest instance
# valid options: NUMPY, XARRAY
PY_EMBED_INGEST_1_TYPE = NUMPY

# output grid for 1st ingest instance. Can be a grid definition or file path
PY_EMBED_INGEST_1_OUTPUT_GRID = G130


# 2nd INGEST INSTANCE
# python script with optional arguments to run for 2nd ingest instance
PY_EMBED_INGEST_2_SCRIPT = {INPUT_BASE}/met_test/scripts/python/read_ascii_numpy.py {INPUT_BASE}/met_test/data/python/fcst.txt FCST

# type of python input to expect for 2nd ingest instance
# valid options: NUMPY, XARRAY
PY_EMBED_INGEST_2_TYPE = NUMPY

# output grid for 2nd ingest instance. Can be a grid definition or file path
PY_EMBED_INGEST_2_OUTPUT_GRID = G130

[dir]
# output directory for 1st ingest instance
# in this example, the full output path is set in PY_EMBED_INGEST_1_OUTPUT_TEMPLATE
PY_EMBED_INGEST_1_OUTPUT_DIR =

# output directory for 2nd ingest instance
# in this example, the full output path is set in PY_EMBED_INGEST_2_OUTPUT_TEMPLATE
PY_EMBED_INGEST_2_OUTPUT_DIR = 

[filename_templates]
# output template to use for 1st ingest instance
# can optionally use [dir] PY_EMBED_INGEST_1_OUTPUT_DIR with this value
PY_EMBED_INGEST_1_OUTPUT_TEMPLATE = {OUTPUT_BASE}/met_tool_wrapper/PyEmbedIngest/test.nc

# output template to use for 2nd ingest instance
# can optionally use [dir] PY_EMBED_INGEST_2_OUTPUT_DIR with this value
PY_EMBED_INGEST_2_OUTPUT_TEMPLATE = {OUTPUT_BASE}/met_tool_wrapper/PyEmbedIngest/regrid_data_plane.nc

MET Configuration

None. RegridDataPlane does not use configuration files.

Python Embedding

This use case calls a Python script to read the input data. The Python script is stored in the MET repository: /path/to/MET/installation/share/met/python/read_ascii_numpy.py

read_ascii_numpy.py

Running METplus

This use case can be run two ways:

1. Passing in PyEmbedIngest.conf then a user-specific system configuration file:

   run_metplus.py -c /path/to/METplus/parm/use_cases/met_tool_wrapper/PyEmbedIngest/PyEmbedIngest.conf -c /path/to/user_system.conf
   

2. Modifying the configurations in parm/metplus_config, then passing in PyEmbedIngest.conf:

   run_metplus.py -c /path/to/METplus/parm/use_cases/met_tool_wrapper/PyEmbedIngest/PyEmbedIngest.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/PyEmbedIngest (relative to OUTPUT_BASE) and will contain the following file:

• test.nc

• regrid_data_plane.nc

Keywords

Note

PyEmbedIngestToolUseCase, PythonEmbeddingFileUseCase, RegridDataPlaneToolUseCase