Add an Nants_telescope property to UVData for eq_coeffs

pyuvdata/uvbase.py

@@ -392,7 +392,9 @@ def __iter__(self, uvparams_only=True):
         """
         if uvparams_only:
             attribute_list = [
-                a for a in dir(self) if isinstance(getattr(self, a), uvp.UVParameter)
+                a
+                for a in dir(self)
+                if a.startswith("_") and isinstance(getattr(self, a), uvp.UVParameter)
             ]
         else:
             attribute_list = [

pyuvdata/uvcal/uvcal.py

@@ -2019,6 +2019,10 @@ def check(
                 "2.5",
                 DeprecationWarning,
             )
+
+        # call metadata_only to make sure that parameter requirements are set properly
+        self.metadata_only
+
         # first run the basic check from UVBase
         super(UVCal, self).check(
             check_extra=check_extra, run_check_acceptability=run_check_acceptability

pyuvdata/uvdata/uvdata.py

@@ -697,6 +697,23 @@ def _set_telescope_requirements(self):
         self.telescope._instrument.required = True
         self.telescope._x_orientation.required = False
 
+    # This is required for eq_coeffs, which has Nants_telescope as one of its
+    # shapes. That's to allow us to line up the antenna_numbers/names with
+    # eq_coeffs so that we know which antenna each eq_coeff goes with.
+    @property
+    def Nants_telescope(self):
+        """
+        The number of antennas in the telescope.
+
+        This property is stored on the Telescope object internally.
+        """
+        return self._telescope.value.Nants
+
+    # TODO: do we want a setter on UVData for this?
+    @Nants_telescope.setter
+    def Nants_telescope(self, val):
+        self._telescope.value.Nants = val
+
     @staticmethod
     def _clear_antpair2ind_cache(obj):
         """Clear the antpair2ind cache."""
@@ -2589,6 +2606,9 @@ def check(
                     "All values in the flex_spw_id_array must exist in the spw_array."
                 )
 
+        # call metadata_only to make sure that parameter requirements are set properly
+        self.metadata_only
+
         # first run the basic check from UVBase
 
         logger.debug("Doing UVBase check...")