Add isclose() method for Quantity objects

This allows us to compare floating point values without having to use
the equality operator.

Signed-off-by: Sahas Subramanian <[email protected]>

Author: shsms

src/frequenz/sdk/timeseries/_quantities.py

@@ -100,6 +100,24 @@ def isinf(self) -> bool:
         """
         return math.isinf(self._base_value)
 
+    def isclose(self, other: Self, rel_tol: float = 1e-9, abs_tol: float = 0.0) -> bool:
+        """Return whether this quantity is close to another.
+
+        Args:
+            other: The quantity to compare to.
+            rel_tol: The relative tolerance.
+            abs_tol: The absolute tolerance.
+
+        Returns:
+            Whether this quantity is close to another.
+        """
+        return math.isclose(
+            self._base_value,
+            other._base_value,  # pylint: disable=protected-access
+            rel_tol=rel_tol,
+            abs_tol=abs_tol,
+        )
+
     def __repr__(self) -> str:
         """Return a representation of this quantity.
 

tests/timeseries/test_quantities.py

@@ -91,6 +91,12 @@ def test_string_representation() -> None:
     assert f"{Fz1(-20000)}" == "-20 kHz"
 
 
+def test_isclose() -> None:
+    """Test the isclose method of the quantities."""
+    assert Fz1(1.024445).isclose(Fz1(1.024445))
+    assert not Fz1(1.024445).isclose(Fz1(1.0))
+
+
 def test_addition_subtraction() -> None:
     """Test the addition and subtraction of the quantities."""
     assert Quantity(1) + Quantity(1, exponent=0) == Quantity(2, exponent=0)