ENH/SE: don't deadreckon position

pyglider/seaexplorer.py

@@ -7,6 +7,7 @@
 import glob
 import logging
 import os
+import warnings
 
 import numpy as np
 import polars as pl
@@ -329,6 +330,29 @@ def _remove_fill_values(df, fill_value=9999):
     return df
 
 
+def _forward_fill(gli, todo='Lat'):
+    """Forward-fill Lat to get the last good value at each row"""
+    gli = gli.with_columns([
+        pl.col(todo).fill_null(strategy="forward").alias("temp_fill")
+    ])
+    gli = gli.with_columns([
+        pl.when(
+            (pl.col(todo) == pl.col("temp_fill").shift(1)) & pl.col("Lat").is_not_null()
+        ).then(np.nan).otherwise(pl.col(todo)).alias(todo)
+    ])
+    gli = gli.drop("temp_fill")
+    return gli
+
+
+def _drop_if(gli, todo='Lat', condit='DeadReckoning', value=1):
+    """Drop Lat if DeadReckoning is 1"""
+    gli = gli.with_columns([
+        pl.when(pl.col(condit) == value).then(np.nan).otherwise(pl.col(todo)).alias(todo)
+    ])
+    return gli
+
+
+
 def raw_to_timeseries(
     indir,
     outdir,
@@ -339,9 +363,44 @@ def raw_to_timeseries(
     maxgap=10,
     interpolate=False,
     fnamesuffix='',
+    deadreckon=False,
 ):
     """
-    A little different than above, for the 4-file version of the data set.
+    Convert raw seaexplorer data to a timeseries netcdf file.
+
+    Parameters
+    ----------
+    indir : str
+        Directory with the raw files are kept.
+    outdir : str
+        Directory to write the matching ``*.nc`` files.
+    deploymentyaml : str
+        YAML text file with deployment information for this glider.
+    kind : 'raw' or 'sub'
+        The type of data to process.  'raw' is the full resolution data, 'sub'
+        is the sub-sampled data.  The default is 'raw'.  Note that realtime data is
+        typically sub-sampled.
+    profile_filt_time : float
+        Time in seconds to use for filtering the profiles.  Default is 100.
+    profile_min_time : float
+        Minimum time in seconds for a profile to be considered a valid profile.
+        Default is 300.
+    maxgap : float
+        Maximum gap in seconds to interpolate over.  Default is 10.
+    interpolate : bool
+        If *True*, interpolate the data to fill in gaps.  Default is False.
+    fnamesuffix : str
+        Suffix to add to the output file name.  Default is ''.
+    deadreckon : bool
+        If *True* use the dead reckoning latitude and longitude data from the glider.  Default
+        is *False*, and latitude and longitude are linearly interpolated between sueface fixes.
+        *False* is the default, and recommended to avoid a-physical underwater jumps.
+
+    Returns
+    -------
+    outname : str
+        Name of the output netcdf file.
+
     """
 
     deployment = utils._get_deployment(deploymentyaml)
@@ -356,6 +415,24 @@ def raw_to_timeseries(
     sensor = pl.read_parquet(f'{indir}/{id}-{kind}pld.parquet')
     sensor = _remove_fill_values(sensor)
 
+    # don't use lat/lon if deadreckoned:
+    if not deadreckon:
+        if not ncvar['latitude']['source'] == 'Lat':
+            warnings.warn("For deadreckon=False it is suggested to use 'Lat' as the "
+                          "source for latitude and 'Lon' as the source for longitude")
+        if 'DeadReckoning' in gli.columns:
+            _log.info('Not using deadreckoning; glider has DeadReckoning column')
+            gli = _drop_if(gli, todo='Lat', condit='DeadReckoning', value=1)
+            gli = _drop_if(gli, todo='Lon', condit='DeadReckoning', value=1)
+        else:
+            _log.info('Not using deadreckoning; glider does not have DeadReckoning column')
+            gli = _drop_if(gli, todo='Lat', condit='NavState', value=116)
+            gli = _drop_if(gli, todo='Lon', condit='NavState', value=116)
+        # drop a lat/lon if it is not unique.  Happens when there
+        # are stale fixes.
+        gli = _forward_fill(gli, todo='Lat')
+        gli = _forward_fill(gli, todo='Lon')
+
     # build a new data set based on info in `deploymentyaml.`
     # We will use ctd as the interpolant
     ds = xr.Dataset()

tests/example-data/example-seaexplorer/deploymentRealtime.yml

@@ -89,7 +89,7 @@ netcdf_variables:
     coordinates:   time depth latitude longitude
 
   latitude:
-    source:       NAV_LATITUDE
+    source:       Lat
     long_name:    latitude
     standard_name: latitude
     units:        degrees_north
@@ -105,7 +105,7 @@ netcdf_variables:
     coordinate_reference_frame:  urn:ogc:crs:EPSG::4326
 
   longitude:
-    source:       NAV_LONGITUDE
+    source:       Lon
     long_name:    longitude
     standard_name: longitude
     units:        degrees_east

tests/example-data/example-seaexplorer/process_deploymentRealTime.py

@@ -29,7 +29,8 @@
     seaexplorer.merge_parquet(rawncdir, rawncdir, deploymentyaml, kind='sub')
 
         # Make level-1 timeseries netcdf file from th raw files...
-    outname = seaexplorer.raw_to_timeseries(rawncdir, l0tsdir, deploymentyaml, kind='sub')
+    outname = seaexplorer.raw_to_timeseries(rawncdir, l0tsdir, deploymentyaml, kind='sub',
+                                            deadreckon=False)
     ncprocess.extract_timeseries_profiles(outname, profiledir, deploymentyaml)
     outname2 = ncprocess.make_gridfiles(outname, griddir, deploymentyaml)
 

tests/test_pyglider.py

@@ -98,7 +98,7 @@ def test_example_seaexplorer_interp_nrt(var):
 seaexplorer.raw_to_rawnc(rawdir, rawncdir, deploymentyaml_raw)
 seaexplorer.merge_parquet(rawncdir, rawncdir, deploymentyaml_raw, kind='raw')
 outname_raw = seaexplorer.raw_to_L0timeseries(
-    rawncdir, l0tsdir, deploymentyaml_raw, kind='raw'
+    rawncdir, l0tsdir, deploymentyaml_raw, kind='raw', deadreckon=True
 )
 output_raw = xr.open_dataset(outname_raw)
 # Open test data file
@@ -147,7 +147,7 @@ def test_example_seaexplorer_metadata_raw():
 )
 
 outname_interp_raw = seaexplorer.raw_to_L0timeseries(
-    rawncdir, l0tsdir_interp_raw, interp_yaml, kind='raw'
+    rawncdir, l0tsdir_interp_raw, interp_yaml, kind='raw', deadreckon=True
 )
 output_interp_raw = xr.open_dataset(outname_interp_raw)