Add a new math module with is_close_to_zero()

Signed-off-by: Leandro Lucarella <[email protected]>

Author: llucax

src/frequenz/core/math.py

@@ -0,0 +1,25 @@
+# License: MIT
+# Copyright © 2023 Frequenz Energy-as-a-Service GmbH
+
+"""Internal math tools."""
+
+import math
+
+
+def is_close_to_zero(value: float, abs_tol: float = 1e-9) -> bool:
+    """Check if a floating point value is close to zero.
+
+    A value of 1e-9 is a commonly used absolute tolerance to balance precision
+    and robustness for floating-point numbers comparisons close to zero. Note
+    that this is also the default value for the relative tolerance.
+    For more technical details, see https://peps.python.org/pep-0485/#behavior-near-zero
+
+    Args:
+        value: the floating point value to compare to.
+        abs_tol: the minimum absolute tolerance. Defaults to 1e-9.
+
+    Returns:
+        whether the floating point value is close to zero.
+    """
+    zero: float = 0.0
+    return math.isclose(a=value, b=zero, abs_tol=abs_tol)