From 5af92382bcee3d9638c85444c304aa83f06d1749 Mon Sep 17 00:00:00 2001
From: Garrett 'Karto' Keating <garrett.keating@cfa.harvard.edu>
Date: Thu, 21 Sep 2023 13:49:26 -0400
Subject: [PATCH] Adding compare_value method to make it easier to check
 UVParameter values (particularly w/ ndarrays)

---
 pyuvdata/parameter.py            | 42 ++++++++++++++++++++++++++++++++
 pyuvdata/tests/test_parameter.py | 27 ++++++++++++++++++++
 2 files changed, 69 insertions(+)

diff --git a/pyuvdata/parameter.py b/pyuvdata/parameter.py
index 7803d8e0dd..3c09521dd3 100644
--- a/pyuvdata/parameter.py
+++ b/pyuvdata/parameter.py
@@ -659,6 +659,48 @@ def check_acceptability(self):
                     )
                     return False, message
 
+    def compare_value(self, value):
+        """
+        Compare UVParameter value to a supplied value.
+
+        Parameters
+        ----------
+        value
+            The value to compare against that stored in the UVParameter object. Must
+            be the same type.
+
+        Returns
+        -------
+        same : bool
+            True if the values are equivalent (or within specified tolerances),
+            otherwise false.
+        """
+        # Catch the case when the values are different types
+        if not (
+            isinstance(value, self.value.__class__)
+            and isinstance(self.value, value.__class__)
+        ):
+            raise ValueError(
+                "UVParameter value and supplied values are of different types."
+            )
+
+        # If these are numeric types, handle them via allclose
+        if isinstance(value, (np.ndarray, int, float, complex)):
+            # Check that we either have a number or an ndarray
+            if not isinstance(value, np.ndarray) or value.shape == self.value.shape:
+                if np.allclose(
+                    value,
+                    self.value,
+                    rtol=self.tols[0],
+                    atol=self.tols[1],
+                    equal_nan=True,
+                ):
+                    return True
+            return False
+        else:
+            # Otherwise just default to checking equality
+            return value == self.value
+
 
 class AngleParameter(UVParameter):
     """
diff --git a/pyuvdata/tests/test_parameter.py b/pyuvdata/tests/test_parameter.py
index 7a8d58823b..94dc0f3bb5 100644
--- a/pyuvdata/tests/test_parameter.py
+++ b/pyuvdata/tests/test_parameter.py
@@ -657,3 +657,30 @@ def test_spoof():
     assert param.value is None
     param.apply_spoof()
     assert param.value == 1.0
+
+
+def test_compare_value_err():
+    param = uvp.UVParameter("_test1", value=3.0, tols=[0, 1], expected_type=float)
+    with pytest.raises(
+        ValueError,
+        match="UVParameter value and supplied values are of different types.",
+    ):
+        param.compare_value("test")
+
+
+@pytest.mark.parametrize(
+    "value,status",
+    [
+        (np.array([1, 2]), False),
+        (np.array([1, 2, 3]), True),
+        (np.array([1.0, 2.0, 3.0]), True),
+        (np.array([2, 3, 4]), True),
+        (np.array([4, 5, 6]), False),
+        (np.array([1, 2, 3, 4, 5, 6]), False),
+    ],
+)
+def test_compare_value(value, status):
+    param = uvp.UVParameter(
+        "_test1", value=np.array([1, 2, 3]), tols=[0, 1], expected_type=float
+    )
+    assert param.compare_value(value) == status