Merge pull request #418 from davidhassell/bounds-units

Fix for setting bounds with different but equivalent units

Changelog.rst

@@ -1,3 +1,13 @@
+version 3.13.1
+--------------
+
+**2022-??-??**
+
+* Fix bug when setting coordinate bounds with different units to their
+  parent coordinates
+  (https://github.com/NCAS-CMS/cf-python/issues/417)
+
+----
 version 3.13.0
 --------------
 

cf/__init__.py

@@ -74,8 +74,8 @@
 
 """
 __Conventions__ = "CF-1.9"
-__date__ = "2022-06-23"
-__version__ = "3.13.0"
+__date__ = "2022-??-??"
+__version__ = "3.13.1"
 
 _requires = (
     "numpy",

cf/mixin/propertiesdatabounds.py

@@ -2625,11 +2625,13 @@ def set_bounds(self, bounds, copy=True):
         units = bounds.Units
         self_units = self.Units
 
-        if data is not None and units and not units.equivalent(self_units):
-            raise ValueError(
-                f"Can't set bounds: {bounds!r} units of {bounds.Units!r} are "
-                f"not equivalent to {self.Units!r}, the units of {self!r}"
-            )
+        if data is not None and units:
+            if not units.equivalent(self_units):
+                raise ValueError(
+                    f"Can't set bounds: {bounds!r} units of {bounds.Units!r} "
+                    f"are not equivalent to {self.Units!r}, the units of "
+                    f"{self!r}"
+                )
 
             bounds.Units = self_units
 

cf/test/test_DimensionCoordinate.py

@@ -462,6 +462,28 @@ def test_DimensionCoordinate__setitem__(self):
         self.assertTrue(d.data.equals(-e.data, verbose=3))
         self.assertTrue(d.bounds.equals(self.dim.bounds, verbose=3))
 
+    def test_DimensionCoordinate_set_bounds(self):
+        c = cf.DimensionCoordinate()
+        data = cf.Data(
+            [1296000.0], units="seconds since 1900-01-01", calendar="360_day"
+        )
+        c.set_data(data)
+
+        bounds = cf.Bounds()
+        data = cf.Data(
+            [[0.0, 30]], units="days since 1900-01-01", calendar="360_day"
+        )
+        bounds.set_data(data)
+
+        c.set_bounds(bounds)
+
+        self.assertEqual(
+            c.bounds.Units,
+            cf.Units(units="seconds since 1900-01-01", calendar="360_day"),
+        )
+
+        self.assertTrue((c.bounds.data.array == [0, 2592000]).all())
+
 
 if __name__ == "__main__":
     print("Run date:", datetime.datetime.now())