Merge pull request #41 from AssessingSolar/numeric-delta_t_dtype

Change delta_t dtype to numeric

Author: AdamRJensen

src/solposx/solarposition/noaa.py

@@ -30,7 +30,7 @@ def noaa(times, latitude, longitude, delta_t=67.0):
     longitude : float
         Longitude in decimal degrees. Positive east of prime meridian,
         negative to west. [degrees]
-    delta_t : float or array, default 67.0
+    delta_t : numeric, default 67.0
         Difference between terrestrial time and UT1.
         If delta_t is None, uses spa.calculate_deltat
         using time.year and time.month from pandas.DatetimeIndex.

src/solposx/solarposition/usno.py

@@ -22,15 +22,15 @@ def usno(times, latitude, longitude, delta_t=67.0, gmst_option=1):
     longitude : float
         Longitude in decimal degrees. Positive east of prime meridian,
         negative to west. [degrees]
-    delta_t : float or array, default 67.0
+    delta_t : numeric, default 67.0
         Difference between terrestrial time and UT1.
         If delta_t is None, uses spa.calculate_deltat
         using time.year and time.month from pandas.DatetimeIndex.
         For most simulations the default delta_t is sufficient.
         The USNO has historical and forecasted delta_t [2]_. [seconds]
-    gmst_option : numeric, default 1
-        Different ways of calculating the Greenwich mean sidereal time. See
-        [1]_.
+    gmst_option : int, default 1
+        Different ways of calculating the Greenwich mean sidereal time.
+        `gmst_option` needs to be either 1, 2, or 3. See [1]_.
 
     Returns
     -------

tests/test_solarposition.py

@@ -489,3 +489,17 @@ def test_noaa_refraction_85_degrees():
         latitude=0, longitude=0,
     )
     assert angles['elevation'].iloc[0] == angles['apparent_elevation'].iloc[0]
+
+
+def test_delta_t_array_input():
+    # test that delta_t can be specified as either an array or float
+    times = pd.date_range('2020-03-23 12', periods=10, tz='UTC')
+    delta_t = np.ones(len(times)) * 67.0
+    # test noaa
+    noaa_array = noaa(times, 50, 10, delta_t=delta_t)
+    noaa_float = noaa(times, 50, 10, delta_t=67.0)
+    pd.testing.assert_frame_equal(noaa_array, noaa_float)
+    # test usno
+    usno_array = usno(times, 50, 10, delta_t=delta_t)
+    usno_float = usno(times, 50, 10, delta_t=67.0)
+    pd.testing.assert_frame_equal(usno_array, usno_float)