add coord specification in vectors queries

Author: m-stclair

astroquery/jplhorizons/core.py

@@ -550,7 +550,7 @@ def ephemerides_async(self, *, airmass_lessthan=99,
 
         URL = conf.horizons_server
 
-        # check for required information
+        # check for required information and assemble commanddline stub
         if self.id is None:
             raise ValueError("'id' parameter not set. Query aborted.")
         elif isinstance(self.id, dict):
@@ -564,7 +564,7 @@ def ephemerides_async(self, *, airmass_lessthan=99,
             self.location = '500@399'
         if self.epochs is None:
             self.epochs = Time.now().jd
-        # assemble commandline based on self.id_type
+        # expand commandline based on self.id_type
 
         if self.id_type in ['designation', 'name',
                             'asteroid_name', 'comet_name']:
@@ -601,12 +601,9 @@ def ephemerides_async(self, *, airmass_lessthan=99,
             ('EXTRA_PREC', {True: 'YES', False: 'NO'}[extra_precision])])
 
         if isinstance(self.location, dict):
-            request_payload['CENTER'] = 'coord@{:s}'.format(
-                str(self.location['body']))
-            request_payload['COORD_TYPE'] = 'GEODETIC'
-            request_payload['SITE_COORD'] = "'{:f},{:f},{:f}'".format(
-                self.location['lon'], self.location['lat'],
-                self.location['elevation'])
+            request_payload = dict(
+                **request_payload, **self._location_to_params(self.location)
+            )
         else:
             request_payload['CENTER'] = "'" + str(self.location) + "'"
 
@@ -1046,17 +1043,21 @@ def vectors_async(self, *, get_query_payload=False,
 
         URL = conf.horizons_server
 
-        # check for required information
+        # check for required information and assemble commandline stub
         if self.id is None:
             raise ValueError("'id' parameter not set. Query aborted.")
+        elif isinstance(self.id, dict):
+            commandline = (
+                f"g:{self.id['lon']},{self.id['lat']},"
+                f"{self.id['elevation']}@{self.id['body']}"
+            )
+        else:
+            commandline = str(self.id)
         if self.location is None:
             self.location = '500@10'
         if self.epochs is None:
             self.epochs = Time.now().jd
-
-        # assemble commandline based on self.id_type
-        commandline = str(self.id)
-
+        # expand commandline based on self.id_type
         if self.id_type in ['designation', 'name',
                             'asteroid_name', 'comet_name']:
             commandline = ({'designation': 'DES=',
@@ -1074,18 +1075,17 @@ def vectors_async(self, *, get_query_payload=False,
                 commandline += ' CAP{:s};'.format(closest_apparition)
             if no_fragments:
                 commandline += ' NOFRAG;'
-
-        if isinstance(self.location, dict):
-            raise ValueError(('cannot use topographic position in state'
-                              'vectors query'))
+        #
+        # if isinstance(self.location, dict):
+        #     raise ValueError(('cannot use topographic position in state'
+        #                       'vectors query'))
 
         # configure request_payload for ephemerides query
         request_payload = OrderedDict([
             ('format', 'text'),
             ('EPHEM_TYPE', 'VECTORS'),
             ('OUT_UNITS', 'AU-D'),
             ('COMMAND', '"' + commandline + '"'),
-            ('CENTER', ("'" + str(self.location) + "'")),
             ('CSV_FORMAT', ('"YES"')),
             ('REF_PLANE', {'ecliptic': 'ECLIPTIC',
                            'earth': 'FRAME',
@@ -1100,7 +1100,12 @@ def vectors_async(self, *, get_query_payload=False,
             ('VEC_DELTA_T', {True: 'YES', False: 'NO'}[delta_T]),
             ('OBJ_DATA', 'YES')]
         )
-
+        if isinstance(self.location, dict):
+            request_payload = dict(
+                **request_payload, **self._location_to_params(self.location)
+            )
+        else:
+            request_payload['CENTER'] = "'" + str(self.location) + "'"
         # parse self.epochs
         if isinstance(self.epochs, (list, tuple, ndarray)):
             request_payload['TLIST'] = "\n".join([str(epoch) for epoch in
@@ -1148,6 +1153,7 @@ def vectors_async(self, *, get_query_payload=False,
     # ---------------------------------- parser functions
     @staticmethod
     def _prep_loc_dict(loc_dict, attr_name):
+        """prepare coord specification dict for 'location' or 'id'"""
         if {'lat', 'lon', 'elevation'} - set(loc_dict.keys()) != set():
             raise ValueError(
                 f"dict values for '{attr_name}' must contain 'lat', 'lon', "
@@ -1157,6 +1163,19 @@ def _prep_loc_dict(loc_dict, attr_name):
             loc_dict['body'] = 399
         return loc_dict
 
+    @staticmethod
+    def _location_to_params(loc_dict):
+        """translate a 'location' dict to a dict of request parameters"""
+        loc_dict = {
+            "CENTER": f"coord@{loc_dict['body']}",
+            "COORD_TYPE": "GEODETIC",
+            "SITE_COORD": ",".join(
+                str(float(loc_dict[k])) for k in ['lat', 'lon', 'elevation']
+            )
+        }
+        loc_dict["SITE_COORD"] = f"'{loc_dict['SITE_COORD']}'"
+        return loc_dict
+
     def _parse_result(self, response, verbose=None):
         """
         Parse query result to a `~astropy.table.Table` object.