added extra_precision option for ephemerides

tomdonaldson · May 29, 2019 · 678b9f5 · 678b9f5
1 parent 38ceae8
commit 678b9f5
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Showing 4 changed files with 23 additions and 8 deletions.
diff --git a/astroquery/jplhorizons/core.py b/astroquery/jplhorizons/core.py
@@ -146,6 +146,7 @@ def ephemerides_async(self, airmass_lessthan=99,
                           refsystem='J2000',
                           closest_apparition=False, no_fragments=False,
                           quantities=conf.eph_quantities,
+                          extra_precision=False,
                           get_query_payload=False,
                           get_raw_response=False, cache=True):
         """
@@ -434,13 +435,15 @@ def ephemerides_async(self, airmass_lessthan=99,
             selection; default: False. Do not use this option for
             non-cometary objects.
         quantities : integer or string, optional
-            single integer or comma-separated list in the form of a string
+            Single integer or comma-separated list in the form of a string
             corresponding to all the
             quantities to be queried from JPL Horizons using the coding
             according to the `JPL Horizons User Manual Definition of
             Observer Table Quantities
             <https://ssd.jpl.nasa.gov/?horizons_doc#table_quantities>`_;
             default: all quantities
+        extra_precision : boolean, optional
+            Enables extra precision in RA and DEC values; default: False
         get_query_payload : boolean, optional
             When set to `True` the method returns the HTTP request
             parameters as a dict, default: False
@@ -528,7 +531,8 @@ def ephemerides_async(self, airmass_lessthan=99,
             ('ANG_FORMAT', ('DEG')),
             ('APPARENT', ({False: 'AIRLESS',
                            True: 'REFRACTED'}[refraction])),
-            ('REF_SYSTEM', (refsystem))])
+            ('REF_SYSTEM', (refsystem)),
+            ('EXTRA_PREC', {True: 'YES', False: 'NO'}[extra_precision])])
 
         if isinstance(self.location, dict):
             if ('lon' not in self.location or 'lat' not in self.location or
@@ -763,8 +767,7 @@ def elements_async(self, get_query_payload=False,
             ('REF_PLANE', {'ecliptic': 'ECLIPTIC', 'earth': 'FRAME',
                            'body': "'BODY EQUATOR'"}[refplane]),
             ('TP_TYPE', {'absolute': 'ABSOLUTE',
-                         'relative': 'RELATIVE'}[tp_type])]
-        )
+                         'relative': 'RELATIVE'}[tp_type])])
 
         # parse self.epochs
         if isinstance(self.epochs, (list, tuple, ndarray)):

diff --git a/astroquery/jplhorizons/tests/test_jplhorizons.py b/astroquery/jplhorizons/tests/test_jplhorizons.py
@@ -177,7 +177,8 @@ def test_ephemerides_query_payload(self):
             ('STOP_TIME', '"2080-02-01"'),
             ('STEP_SIZE', '"3h"'),
             ('AIRMASS', '1.2'),
-            ('SKIP_DAYLT', 'YES')])
+            ('SKIP_DAYLT', 'YES'),
+            ('EXTRA_PREC', 'NO')])
 
     def test_elements_query_payload():
         res = (jplhorizons.Horizons(id='Ceres', location='500@10',
@@ -197,6 +198,7 @@ def test_elements_query_payload():
             ('REF_SYSTEM', 'J2000'),
             ('REF_PLANE', 'ECLIPTIC'),
             ('TP_TYPE', 'ABSOLUTE'),
+            ('EXTRA_PREC', 'NO')
             ('TLIST', '2451544.5')])
 
 

diff --git a/astroquery/jplhorizons/tests/test_jplhorizons_remote.py b/astroquery/jplhorizons/tests/test_jplhorizons_remote.py
@@ -370,3 +370,11 @@ def test_vectors_delta_T(self):
 
         vec = obj.vectors(delta_T=True)
         assert_quantity_allclose(vec['delta_T'][0], 69.184373)
+
+    def test_ephemerides_extraprecision(self):
+        obj = jplhorizons.Horizons(id='1', epochs=2458500, location='G37')
+
+        vec_simple = obj.ephemerides(extra_precision=False)
+        vec_highprec = obj.ephemerides(extra_precision=True)
+
+        assert (vec_simple['RA'][0]-vec_highprec['RA'][0]) > 1e-7
diff --git a/docs/jplhorizons/jplhorizons.rst b/docs/jplhorizons/jplhorizons.rst
@@ -166,9 +166,11 @@ default).. For comets, the options ``closest_apparation`` and
 ``no_fragments`` are available, which select the closest apparition in
 time and reject fragments, respectively. Note that these options
 should only be used for comets and will crash the query for other
-object types.  Furthermore, ``get_query_payload=True`` skips the query
-and only returns the query payload, whereas ``get_raw_response=True``
-the raw query response instead of the astropy table returns.
+object types. Extra precision in the queried properties can be
+requested using the ``extra_precision`` option. Furthermore,
+``get_query_payload=True`` skips the query and only returns the query
+payload, whereas ``get_raw_response=True`` the raw query response
+instead of the astropy table returns.
 
 :meth:`~astroquery.jplhorizons.HorizonsClass.ephemerides` queries by
 default all available quantities from the JPL Horizons servers. This