Per #48, add instructions to run METplus use case on HPC using apptainer

docs/Users_Guide/running.rst

@@ -2,15 +2,63 @@
 Running I-WRF Containers
 ************************
 
-On an HPC Cluster with Singularity
-==================================
+On an HPC Cluster with Apptainer
+================================
 
 WRF
 ---
 
 METplus
 -------
 
+The following commands were run on Casper.
+
+Load the apptainer module::
+
+   module load apptainer
+
+Change directory to scratch and pull the container from DockerHub.
+This will create a `.sif` file in the current directory::
+
+   cd ${SCRATCH}
+   apptainer pull docker://dtcenter/metplus:6.0.0-beta4
+
+Create a directory to store the output::
+
+   mkdir ${SCRATCH}/metplus_out
+
+Set environment variable to bind directories to container
+(note: this can also be accomplished by passing the value on the command line
+using the --bind argument)
+
+* Input data directories for WRF, raob, and metar input data
+   * WRF: /glade/derecho/scratch/jaredlee/nsf_i-wrf/matthew to /data/input/wrf
+   * RAOB: /glade/campaign/ral/wsap/i-wrf/data/hurr-matthew/madis/point/raob/netcdf to /data/input/obs/raob
+   * METAR: /glade/campaign/ral/wsap/i-wrf/data/hurr-matthew/madis/point/metar/netcdf to /data/input/obs/metar
+* Config directory containing METplus use case configuration file
+   * /glade/u/home/mccabe/i-wrf/use_cases/Hurricane_Matthew/METplus to /config
+* Output directory to write output
+   * ${SCRATCH}/metplus_out to /data/output
+
+::
+
+   LOCAL_METPLUS_CONFIG_DIR=/glade/u/home/mccabe/i-wrf/use_cases/Hurricane_Matthew/METplus
+   LOCAL_FCST_INPUT_DIR=/glade/derecho/scratch/jaredlee/nsf_i-wrf/matthew
+   LOCAL_UPPER_AIR_OBS_INPUT_DIR=/glade/campaign/ral/wsap/i-wrf/data/hurr-matthew/madis/point/raob/netcdf
+   LOCAL_SURFACE_OBS_INPUT_DIR=/glade/campaign/ral/wsap/i-wrf/data/hurr-matthew/madis/point/metar/netcdf
+   LOCAL_OUTPUT_DIR=${SCRATCH}/metplus_out
+
+   export APPTAINER_BIND="${LOCAL_METPLUS_CONFIG_DIR}:/config,${LOCAL_FCST_INPUT_DIR}:/data/input/wrf,${LOCAL_UPPER_AIR_OBS_INPUT_DIR}:/data/input/obs/raob,${LOCAL_SURFACE_OBS_INPUT_DIR}:/data/input/obs/metar,${LOCAL_OUTPUT_DIR}:/data/output"
+
+Execute the run_metplus.py command inside the container to run the use case::
+
+   apptainer exec metplus_6.0.0-beta4.sif /metplus/METplus/ush/run_metplus.py /config/PointStat_matthew.conf
+
+Check that the output data was created locally::
+
+   ls ${SCRATCH}/metplus_out/point_stat -1
+
+
 Visualization
 -------------