Enhance `@value` NetCDF dimension lookup logic to support negative values

[JohnHalleyGotway]

Describe the Enhancement

@georgemccabe ran into an issue with the @value lookup logic when reading a WRF NetCDF file into MET. Attempting @value dimension lookup fails when the value is negative.

Run the following on seneca:

/d1/projects/MET/MET_regression/develop/latest/bin/plot_data_plane \
/d1/personal/mccabe/wrf_renewable/wrf/20250406_06/wrfout/wrfout_zlev_d01_2025-04-07_12:00:00 \
plot.ps \
'name="S_ZL"; level="(0,@-100,*,*)";'

And note the runtime error:

DEBUG 1: Opening data file: wrfout_zlev_d01_2025-04-07_12:00:00
WARNING: 
WARNING: WrfFile::data(NcVar *, const LongArray &, DataPlane &, double &) const -> bad arguments:
Nelements = 4
Nalloc    = 4
AllocInc  = 10
Element # 0 = 0
Element # 1 = -9999
Element # 2 = -12345
Element # 3 = -12345
ERROR  : 
ERROR  : LongArray::operator[](int) -> range check error ... -1
ERROR  : 

Then run ncdump and ncgen to replace all the Z_ZL values from negative to positive and rerun:

/d1/projects/MET/MET_regression/develop/latest/bin/plot_data_plane \
/d1/personal/mccabe/wrf_renewable/wrf/20250406_06/wrfout/wrfout_zlev_d01_2025-04-07_12:00:00 \
plot.ps \
'name="S_ZL"; level="(0,@-100,*,*)";' 

Which runs successfully:

This issue is to update the MET WRF NetCDF library (as well as other NetCDF libraries) to support @value lookup logic for values < 0.

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PRJ014651 -- code maintenance

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[georgemccabe]

I also discovered that a seg fault occurs with a specific misconfiguration in point_stat that is related to this issue.

UPDATE: The seg fault also occurs in plot_data_plane:

/d1/projects/MET/MET_regression/develop/latest/bin/plot_data_plane /d1/personal/mccabe/wrf_renewable/wrf/20250406_06/wrfout/wrfout_d01_2025-04-07_12:00:00 plot.ps 'name="S_ZL"; level="(0,@100,*,*)";'

This produces a seg fault (wrong forecast file and bad @ lookup value):

export METPLUS_CLIMO_CDF_DICT="";
export METPLUS_CLIMO_MEAN_DICT="";
export METPLUS_CLIMO_STDEV_DICT="";
export METPLUS_DESC="desc = \"NA\";";
export METPLUS_DUPLICATE_FLAG="";
export METPLUS_FCST_CLIMO_MEAN_DICT="";
export METPLUS_FCST_CLIMO_STDEV_DICT="";
export METPLUS_FCST_FIELD="field = [{ name=\"S_ZL\"; level=\"(0,@100,*,*)\"; }];";
export METPLUS_FCST_FILE_TYPE="";
export METPLUS_HIRA_DICT="";
export METPLUS_HSS_EC_VALUE="";
export METPLUS_INTERP_DICT="";
export METPLUS_LAND_MASK_DICT="";
export METPLUS_LAPSE_RATE_CORRECTION_DICT="";
export METPLUS_MASK_DICT="";
export METPLUS_MESSAGE_TYPE="message_type = [\"ADPUPA\", \"ADPSFC\"];";
export METPLUS_MESSAGE_TYPE_GROUP_MAP="";
export METPLUS_MET_CONFIG_OVERRIDES="";
export METPLUS_MODEL="model = \"WRF\";";
export METPLUS_MSL_AGL_CONVERSION_DICT="";
export METPLUS_OBS_CLIMO_MEAN_DICT="";
export METPLUS_OBS_CLIMO_STDEV_DICT="";
export METPLUS_OBS_FIELD="field = [{ name=\"velocity\"; level=\"Z100\"; }];";
export METPLUS_OBS_FILE_TYPE="";
export METPLUS_OBS_PERC_VALUE="";
export METPLUS_OBS_QUALITY_EXC="";
export METPLUS_OBS_QUALITY_INC="";
export METPLUS_OBS_SUMMARY="";
export METPLUS_OBS_WINDOW_DICT="obs_window = {beg = -900;end = 900;}";
export METPLUS_OBTYPE_AS_GROUP_VAL_FLAG="";
export METPLUS_OUTPUT_FLAG_DICT="output_flag = {cnt = STAT;}";
export METPLUS_OUTPUT_PREFIX="";
export METPLUS_POINT_WEIGHT_FLAG="";
export METPLUS_REGRID_DICT="";
export METPLUS_SEEPS_P1_THRESH="";
export METPLUS_TOPO_MASK_DICT="";
export METPLUS_UGRID_COORDINATES_FILE="";
export METPLUS_UGRID_DATASET="";
export METPLUS_UGRID_MAX_DISTANCE_KM="";
export MET_TMP_DIR="/tmp";
export OMP_NUM_THREADS="1";

/d1/projects/MET/MET_regression/develop/latest/bin/point_stat -v 2 \
  /d1/personal/mccabe/wrf_renewable/wrf/20250406_06/wrfout/wrfout_d01_2025-04-07_12:00:00 \
  "PYTHON_NUMPY= /home/mccabe/i-wrf/use_cases/Renewable_Energy/METplus/read_nysm_obs.py --debug /d1/personal/mccabe/wrf_renewable/obs/profiler/20250407.nc velocity --station_file /d1/personal/mccabe/wrf_renewable/obs/profiler.csv" \
  /d1/personal/mccabe/METplus/metplus/parm/met_config/PointStatConfig_wrapped \
  -outdir /d1/personal/mccabe/out/point_stat/

If you change the forecast file path to the wrfout_zlev (correct) forecast file:

/d1/projects/MET/MET_regression/develop/latest/bin/point_stat -v 2 \
  /d1/personal/mccabe/wrf_renewable/wrf/20250406_06/wrfout/wrfout_zlev_d01_2025-04-07_12:00:00 \
  "PYTHON_NUMPY= /home/mccabe/i-wrf/use_cases/Renewable_Energy/METplus/read_nysm_obs.py --debug /d1/personal/mccabe/wrf_renewable/obs/profiler/20250407.nc velocity --station_file /d1/personal/mccabe/wrf_renewable/obs/profiler.csv" \
  /d1/personal/mccabe/METplus/metplus/parm/met_config/PointStatConfig_wrapped \
  -outdir /d1/personal/mccabe/out/point_stat/

It reports an error about the @ lookup:

WARNING: WrfFile::data(NcVar *, const LongArray &, DataPlane &, double &) const -> bad arguments:
Nelements = 4
Nalloc    = 4
AllocInc  = 10
Element # 0 = 0
Element # 1 = -123456
Element # 2 = -12345
Element # 3 = -12345
ERROR  :
ERROR  : LongArray::operator -> range check error ... -1

If you use the original incorrect forecast file, but set:

export METPLUS_FCST_FIELD="field = [{ name=\"S_ZL\"; level=\"(0,0,*,*)\"; }];";

/d1/projects/MET/MET_regression/develop/latest/bin/point_stat -v 2 \
  /d1/personal/mccabe/wrf_renewable/wrf/20250406_06/wrfout/wrfout_d01_2025-04-07_12:00:00 \
  "PYTHON_NUMPY= /home/mccabe/i-wrf/use_cases/Renewable_Energy/METplus/read_nysm_obs.py --debug /d1/personal/mccabe/wrf_renewable/obs/profiler/20250407.nc velocity --station_file /d1/personal/mccabe/wrf_renewable/obs/profiler.csv" \
  /d1/personal/mccabe/METplus/metplus/parm/met_config/PointStatConfig_wrapped \
  -outdir /d1/personal/mccabe/out/point_stat/

DEBUG 2: Reading data for S_ZL(0,0,,).
WARNING:
WARNING: process_fcst_climo_files() -> no fields matching S_ZL(0,0,,) found in file: /d1/personal/mccabe/wrf_renewable/wrf/20250406_06/wrfout/wrfout_d01_2025-04-07_12:00:00
WARNING:
ERROR  :
ERROR  : process_fcst_climo_files() -> no requested forecast data found!  Exiting...