Merge pull request #163 from sot/fix-convert-time-spk

Allow None input to convert_time_format_spk

chandra_aca/planets.py

@@ -134,7 +134,7 @@ def convert_time_format_spk(time, fmt_out):
     ndarray or numpy scalar
         Converted time or times
     """
-    if fmt_out not in ("jd", "secs"):
+    if fmt_out not in ("jd", "secs") or time is None:
         return getattr(CxoTime(time).tdb, fmt_out)
 
     # Check if input is in "secs" by determining if it is a float type scalar or array

chandra_aca/tests/test_planets.py

@@ -9,6 +9,7 @@
 from testr.test_helper import has_internet
 
 from chandra_aca.planets import (
+    convert_time_format_spk,
     get_planet_angular_sep,
     get_planet_barycentric,
     get_planet_chandra,
@@ -194,3 +195,11 @@ def test_get_planet_ang_separation_array(obs_pos, exp_sep):
     ra0, dec0 = 304.89116, -20.08328
     sep = get_planet_angular_sep("jupiter", ra0, dec0, times, observer_position=obs_pos)
     assert np.allclose(sep * 3600, exp_sep, atol=1e-2, rtol=0)
+
+
+def test_convert_time_format_spk_none():
+    """Test bug fix where convert_time_format_spk failed when time was None"""
+    time0 = convert_time_format_spk(None, "secs")
+    time1 = CxoTime(None).secs
+    # Times within 10 seconds
+    assert np.isclose(time0, time1, atol=10, rtol=0)