fix(ch_util): Import objects directly from caput.time (#75)

This changes imports of objects moved from `ch_util.ephemeris`
to `caput.time` to use the `caput.time` version directly, rather
than importing that same `caput` object via its import into
`ephemeris`.

This is more prep-work for splitting `ch_util.ephemeris`.

ch_util/andata.py

@@ -10,14 +10,10 @@
 import h5py
 from bitshuffle import h5
 
-tmp = h5  # To appease linters who complain about unused imports.
+from caput import memh5, tod
+import caput.time as ctime
 
-# If the `caput` package is available, get `memh5` from there.  Otherwise, use
-# the version of memh5 that ships with `ch_util`, eliminating the dependency.
-try:
-    from caput import memh5, tod
-except ImportError:
-    raise ImportError("Could not import memh5 or tod. Have you installed caput?")
+tmp = h5  # To appease linters who complain about unused imports.
 
 
 ni_msg = "Ask Kiyo to implement this."
@@ -326,12 +322,7 @@ def timestamp(self):
 
     @staticmethod
     def convert_time(time):
-        try:
-            from .ephemeris import ensure_unix
-        except ValueError:
-            from .ephemeris import ensure_unix
-
-        return ensure_unix(time)
+        return ctime.ensure_unix(time)
 
 
 class CorrData(BaseData):
@@ -1223,8 +1214,6 @@ def from_acq_h5(
         data : HKPData
         """
 
-        from caput import time as ctime
-
         metrics = metrics if metrics is not None else datasets
 
         if "mode" not in kwargs:

ch_util/cal_utils.py

@@ -2682,7 +2682,7 @@ def get_reference_times_dataset_id(
         logger = logging.getLogger(__name__)
 
     # Dataset IDs before this date are untrustworthy
-    ds_start = ephemeris.datetime_to_unix(datetime(2020, 11, 1))
+    ds_start = ctime.datetime_to_unix(datetime(2020, 11, 1))
     if (times < ds_start).any():
         raise ValueError(
             "Dataset IDs before 2020/11/01 are corrupt, so this method won't work. "

ch_util/chan_monitor.py

@@ -2,6 +2,9 @@
 
 import numpy as np
 import copy
+
+import caput.time as ctime
+
 from chimedb import data_index
 from ch_util import ephemeris, finder
 
@@ -14,7 +17,7 @@
 )  # Cylinder rotation matrix
 C = 2.9979e8
 PHI = ephemeris.CHIMELATITUDE * np.pi / 180.0  # DRAO Latitue
-SD = 24.0 * 3600.0 * ephemeris.SIDEREAL_S  # Sidereal day
+SD = 24.0 * 3600.0 * ctime.SIDEREAL_S  # Sidereal day
 
 _DEFAULT_NODE_SPOOF = {"scinet_online": "/scratch/k/krs/jrs65/chime/archive/online/"}
 # _DEFAULT_NODE_SPOOF = {'gong': '/mnt/gong/archive'} # For tests on Marimba
@@ -739,7 +742,7 @@ def fromdate(
         bsep2=218,
     ):
         """Initialize class from date"""
-        t1 = ephemeris.datetime_to_unix(date)
+        t1 = ctime.datetime_to_unix(date)
         return cls(
             t1,
             freq_sel=freq_sel,
@@ -933,7 +936,7 @@ def set_metadata(self, tms, input_map):
         from ch_util import tools
 
         # Get CHIME ON channels:
-        half_time = ephemeris.unix_to_datetime(tms[int(len(tms) // 2)])
+        half_time = ctime.unix_to_datetime(tms[int(len(tms) // 2)])
         corr_inputs = tools.get_correlator_inputs(half_time)
         self.corr_inputs = tools.reorder_correlator_inputs(input_map, corr_inputs)
         pwds = tools.is_chime_on(self.corr_inputs)  # Which inputs are CHIME ON antennas
@@ -954,7 +957,7 @@ def get_prod_sel(self, data):
 
         input_map = data.input
         tms = data.time
-        half_time = ephemeris.unix_to_datetime(tms[int(len(tms) // 2)])
+        half_time = ctime.unix_to_datetime(tms[int(len(tms) // 2)])
         corr_inputs = tools.get_correlator_inputs(half_time)
         corr_inputs = tools.reorder_correlator_inputs(input_map, corr_inputs)
         pwds = tools.is_chime_on(corr_inputs)  # Which inputs are CHIME ON antennas
@@ -1099,8 +1102,8 @@ def set_acq_list(self):
         self.night_acq_list = f_night.get_results()
 
         # Create a list of acquisitions that flag out sunrise, sun transit, and sunset
-        mm = ephemeris.unix_to_datetime(self.t1).month
-        dd = ephemeris.unix_to_datetime(self.t1).day
+        mm = ctime.unix_to_datetime(self.t1).month
+        dd = ctime.unix_to_datetime(self.t1).day
         mm = mm + float(dd) / 30.0
 
         fct = 3.0

ch_util/data_quality.py

@@ -16,6 +16,8 @@
 
 import numpy as np
 
+import caput.time as ctime
+
 import ch_util.ephemeris as ch_eph
 from ch_util import andata
 from ch_util import tools
@@ -364,7 +366,7 @@ def _cut_non_chime(data, visi, chan_array, inputs=None):
     input_map = data.input
     tmstp = data.index_map["time"]["ctime"]  # time stamp
     # Datetime halfway through data:
-    half_time = ch_eph.unix_to_datetime(tmstp[int(len(tmstp) // 2)])
+    half_time = ctime.unix_to_datetime(tmstp[int(len(tmstp) // 2)])
     # Get information on correlator inputs, if not already supplied
     if inputs is None:
         inputs = tools.get_correlator_inputs(half_time)
@@ -899,7 +901,7 @@ def _create_plot(
 
     # For title, use start time stamp:
     title = "Good channels result for {0}".format(
-        ch_eph.unix_to_datetime(tmstp1[0]).date()
+        ctime.unix_to_datetime(tmstp1[0]).date()
     )
 
     # I need to know the slot for each channel:
@@ -985,14 +987,14 @@ def get_slot(channel):
                 if time_unit == "days":
                     plt.xlabel(
                         "Time (days since {0} UTC)".format(
-                            ch_eph.unix_to_datetime(tmstp1[0])
+                            ctime.unix_to_datetime(tmstp1[0])
                         ),
                         fontsize=10,
                     )
                 else:
                     plt.xlabel(
                         "Time (hours since {0} UTC)".format(
-                            ch_eph.unix_to_datetime(tmstp1[0])
+                            ctime.unix_to_datetime(tmstp1[0])
                         ),
                         fontsize=10,
                     )

ch_util/finder.py

@@ -46,6 +46,8 @@
 import peewee as pw
 import re
 
+import caput.time as ctime
+
 import chimedb.core as db
 import chimedb.data_index as di
 from . import layout, ephemeris
@@ -664,8 +666,8 @@ def set_time_range(self, start_time=None, end_time=None):
             start_time = 0
         if end_time is None:
             end_time = time.time()
-        start_time = ephemeris.ensure_unix(start_time)
-        end_time = ephemeris.ensure_unix(end_time)
+        start_time = ctime.ensure_unix(start_time)
+        end_time = ctime.ensure_unix(end_time)
         old_start_time, old_end_time = self.time_range
         start_time = max(start_time, old_start_time)
         end_time = min(end_time, old_end_time)
@@ -733,8 +735,8 @@ def _format_time_interval(self, start_time, end_time):
             start_time = 0
         if end_time is None:
             end_time = time.time()
-        start_time = ephemeris.ensure_unix(start_time)
-        end_time = ephemeris.ensure_unix(end_time)
+        start_time = ctime.ensure_unix(start_time)
+        end_time = ctime.ensure_unix(end_time)
         range_start, range_end = self.time_range
         start_time = max(start_time, range_start)
         end_time = min(end_time, range_end)
@@ -915,11 +917,9 @@ def include_RA_interval(self, start_RA, end_RA):
         Total 242094.394565 seconds of data.
         """
 
-        from . import ephemeris
-
         delta_RA = (end_RA - start_RA) % 360
         mid_RA = (start_RA + delta_RA / 2.0) % 360
-        time_delta = delta_RA * 4 * 60.0 * ephemeris.SIDEREAL_S
+        time_delta = delta_RA * 4 * 60.0 * ctime.SIDEREAL_S
         self.include_transits(mid_RA, time_delta=time_delta)
 
     def exclude_RA_interval(self, start_RA, end_RA):
@@ -938,11 +938,10 @@ def exclude_RA_interval(self, start_RA, end_RA):
         Look under include_RA_interval for very similar example.
 
         """
-        from . import ephemeris
 
         delta_RA = (end_RA - start_RA) % 360
         mid_RA = (start_RA + delta_RA / 2.0) % 360
-        time_delta = delta_RA * 4 * 60.0 * ephemeris.SIDEREAL_S
+        time_delta = delta_RA * 4 * 60.0 * ctime.SIDEREAL_S
         self.exclude_transits(mid_RA, time_delta=time_delta)
 
     def include_transits(self, body, time_delta=None):
@@ -996,7 +995,7 @@ def include_26m_obs(self, source, require_quality=True):
 
         Examples
         --------
-        >>> from ch_util import (finder, ephemeris)
+        >>> from ch_util import finder
         >>> from datetime import datetime
         >>> f = finder.Finder()
         >>> f.only_corr()
@@ -1204,8 +1203,8 @@ def get_results_acq(self, acq_ind, file_condition=None):
                     start, stop = layout.get_global_flag_times(f.id)
                     if stop is None:
                         stop = time.time()
-                    start = ephemeris.ensure_unix(start)
-                    stop = ephemeris.ensure_unix(stop)
+                    start = ctime.ensure_unix(start)
+                    stop = ctime.ensure_unix(stop)
                     flag_times.append((start, stop))
                 overlap = _check_intervals_overlap(time_intervals, flag_times)
             if mode is GF_WARN:
@@ -1246,8 +1245,8 @@ def get_results_acq(self, acq_ind, file_condition=None):
                     start, stop = f.start_time, f.finish_time
                     if stop is None:
                         stop = time.time()
-                    start = ephemeris.ensure_unix(start)
-                    stop = ephemeris.ensure_unix(stop)
+                    start = ctime.ensure_unix(start)
+                    stop = ctime.ensure_unix(stop)
                     flag_times.append((start, stop))
                 overlap = _check_intervals_overlap(time_intervals, flag_times)
                 if overlap:
@@ -1326,15 +1325,13 @@ def print_acq_info(self):
 
         """
 
-        from . import ephemeris
-
         print("acquisition | name | start | length (hrs) | N files")
         row_proto = "%4d  |  %-36s  |  %s  |  %7.2f  |  %4d"
         for ii, acq in enumerate(self.acqs):
             start = acq.start_time
             finish = acq.finish_time
             length = (finish - start) / 3600.0
-            start = ephemeris.unix_to_datetime(start)
+            start = ctime.unix_to_datetime(start)
             start = start.strftime("%Y-%m-%d %H:%M")
             name = acq.name
             n_files = acq.n_timed_files

ch_util/fluxcat.py

@@ -22,6 +22,8 @@
 import time
 
 from caput import misc
+import caput.time as ctime
+
 from . import ephemeris
 from .tools import ensure_list
 
@@ -843,7 +845,7 @@ def skyfield(self):
         """Skyfield star representation :class:`skyfield.starlib.Star`
         for the source.
         """
-        return ephemeris.skyfield_star_from_ra_dec(self.ra, self.dec, self.name)
+        return ctime.skyfield_star_from_ra_dec(self.ra, self.dec, self.name)
 
     @property
     def freq(self):