Add more common operations to Quantity

src/frequenz/quantities/_quantity.py

@@ -139,6 +139,16 @@ def base_value(self) -> float:
         """
         return self._base_value
 
+    def __round__(self, ndigits: int | None = None) -> Self:
+        """Round this quantity to the given number of digits.
+
+        Args:
+            ndigits: The number of digits to round to.
+
+        Returns:
+            The rounded quantity.
+        """
+        return self._new(round(self._base_value, ndigits))
     @property
     def base_unit(self) -> str | None:
         """Return the base unit of this quantity.

tests/test_quantities.py

@@ -234,6 +234,11 @@ def test_isclose() -> None:
     assert not Fz1(1.024445).isclose(Fz1(1.0))
 
 
+@hypothesis.given(value=st.floats(allow_nan=False, allow_infinity=False))
+@pytest.mark.parametrize("ndigits", [0, 1, 2, 3])
+def test_round(value: float, ndigits: int) -> None:
+    """Test the rounding of the quantities."""
+    assert round(Quantity(value), ndigits) == Quantity(round(value, ndigits))
 def test_addition_subtraction() -> None:
     """Test the addition and subtraction of the quantities."""
     assert Quantity(1) + Quantity(1, exponent=0) == Quantity(2, exponent=0)