ENH: slocum logfile parser

Author: jklymak

pyglider/slocum.py

@@ -13,6 +13,7 @@
 import yaml
 import pyglider.utils as utils
 import xml.etree.ElementTree as ET
+from datetime import datetime
 
 
 _log = logging.getLogger(__name__)
@@ -848,5 +849,66 @@ def parse_gliderState(fname):
     return dat
 
 
+def parse_logfiles(files):
+    """
+    Parse time, lat, lon, and amph_total from glider logfiles.
+
+    Parameters
+    ----------
+    files : list of strings or Paths
+        List of logfiles to parse.  Should be sorted.
+
+    Returns
+    -------
+    out : xarray
+        xarray data set with fields time, lon, lat, ampH indexed by surfacing.
+        More could be added.
+    """
+
+    times = [''] * 10000
+    gps = [''] * 10000
+    amph = [''] * 10000
+    ntimes = 0
+    for fn in files:
+        found_time = False
+
+        with open(fn, 'r') as fin:
+            for l in fin:
+                if 'Curr Time:' in l:
+                    times[ntimes] = l
+                    ntimes += 1
+                    found_time=True
+                if found_time and 'GPS Location' in l:
+                    gps[ntimes - 1] = l
+                if found_time and "sensor:m_coulomb_amphr_total" in l:
+                    amph[ntimes-1] = l
+    amph = amph[:ntimes]
+    gps = gps[:ntimes]
+    times = times[:ntimes]
+
+    # now parse them
+    out = xr.Dataset(coords={'time': ('surfacing', np.zeros(ntimes, dtype='datetime64[s]'))})
+    out['ampH'] = ('surfacing', np.zeros(ntimes) * np.NaN)
+    out['lon'] = ('surfacing', np.zeros(ntimes) * np.NaN)
+    out['lat'] = ('surfacing', np.zeros(ntimes) * np.NaN)
+
+    for i in range(ntimes):
+        timestring = times[i][11:-13]
+        out['time'][i] = np.datetime64(datetime.strptime(timestring, '%a %b %d %H:%M:%S %Y'))
+        try:
+            st = amph[i].index('=')
+            en = amph[i][st:].index(' ') + st
+            out['ampH'][i] = float(amph[i][(st+1):en])
+
+            #        GPS Location:  4912.737 N -12357.253 E measured    110.757 secs ago
+            sp = gps[i].split(' ')
+            out['lat'][i] = utils.nmea2deg(float(sp[3]))
+            out['lon'][i] = utils.nmea2deg(float(sp[5]))
+        except:
+            pass
+
+    return out
+
+
 __all__ = ['binary_to_rawnc', 'merge_rawnc', 'raw_to_timeseries',
-           'parse_glider_state']
+           'parse_glider_state', 'parse_logfiles']