From 8cfe88ec6a7d180e25d8472e1546b3987e716147 Mon Sep 17 00:00:00 2001
From: Garrett 'Karto' Keating <garrett.keating@cfa.harvard.edu>
Date: Tue, 19 Mar 2024 09:57:46 -0400
Subject: [PATCH] Minor updates and fixes based on SMA user testing.

---
 pyuvdata/uvcal/ms_cal.py           | 12 +++++++-----
 pyuvdata/uvcal/tests/test_uvcal.py |  1 +
 pyuvdata/uvcal/uvcal.py            |  5 +++++
 3 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/pyuvdata/uvcal/ms_cal.py b/pyuvdata/uvcal/ms_cal.py
index 63c27a5f02..488ff75f1e 100644
--- a/pyuvdata/uvcal/ms_cal.py
+++ b/pyuvdata/uvcal/ms_cal.py
@@ -205,7 +205,7 @@ def read_ms_cal(
         # Don't think CASA is going to support a non-sky based model, but hey, who knows
         self.cal_style = "sky"
         self.gain_convention = "divide"  # N.b., manually verified by Karto in CASA v6.4
-        self.Nsources = len(np.unique(tb_main.getcol("FIELD_ID")))
+        self.Nphase = len(np.unique(tb_main.getcol("FIELD_ID")))
 
         # Just assume that the gain scale is always in Jy
         self.gain_scale = "Jy"
@@ -221,8 +221,6 @@ def read_ms_cal(
             self.freq_array = None
             self.channel_width = None
             self.flex_spw_id_array = None
-            self.Nfreqs = 1
-            nchan = self.Nspws
 
         self.sky_catalog = "CASA (import)"
 
@@ -300,7 +298,11 @@ def read_ms_cal(
                 # Figure out which spectral slice this corresponds to
                 spw_slice = spw_slice_dict[spw_id]
 
-                # Finally, start plugging in solns to various parameters.
+                # Finally, start plugging in solns to various parameters. Note that
+                # because of the conjugation scheme, normally we'd have to flip this for
+                # CASA, except that the Antenna1 entries appear to be "pre-conjugated",
+                # and thus no flip is necessary for gains solns.
+                # TODO: Verify this is the case for delay solns as well.
                 ms_cal_soln[ant_idx, spw_slice, time_idx, :] = cal_soln
                 self.time_array[time_idx] = time_val
                 self.integration_time[time_idx] = exp_time
@@ -525,7 +527,7 @@ def write_ms_cal(self, filename, clobber=False):
             ms.putcol("ANTENNA1", ant_array)
             ms.putcol("ANTENNA2", refant_array)
             ms.putcol("INTERVAL", interval_array)
-            ms.putcol("EXPOSURE", exposure_array)
+            # ms.putcol("EXPOSURE", exposure_array)
             ms.putcol("SCAN_NUMBER", scan_number_array)
             ms.putcol("OBSERVATION_ID", obs_id_array)
 
diff --git a/pyuvdata/uvcal/tests/test_uvcal.py b/pyuvdata/uvcal/tests/test_uvcal.py
index 9fd78015c0..0e611ff2dd 100644
--- a/pyuvdata/uvcal/tests/test_uvcal.py
+++ b/pyuvdata/uvcal/tests/test_uvcal.py
@@ -89,6 +89,7 @@ def uvcal_data():
         "phase_center_catalog",
         "phase_center_id_array",
         "antenna_diameters",
+        "Nphase",
     ]
     extra_parameters = ["_" + prop for prop in extra_properties]
 
diff --git a/pyuvdata/uvcal/uvcal.py b/pyuvdata/uvcal/uvcal.py
index baaf13d44f..207d959687 100644
--- a/pyuvdata/uvcal/uvcal.py
+++ b/pyuvdata/uvcal/uvcal.py
@@ -506,6 +506,11 @@ def __init__(self):
             "Nsources", required=False, expected_type=int, description=desc
         )
 
+        desc = "Number of sources used."
+        self._Nphase = uvp.UVParameter(
+            "Nphase", required=False, expected_type=int, description=desc
+        )
+
         desc = "Range of baselines used for calibration."
         self._baseline_range = uvp.UVParameter(
             "baseline_range",