Issue #9165: Add math.isfinite and cmath.isfinite.
diff --git a/Doc/library/math.rst b/Doc/library/math.rst
index 9c3bd03..22f6f5f 100644
--- a/Doc/library/math.rst
+++ b/Doc/library/math.rst
@@ -97,6 +97,12 @@
<http://code.activestate.com/recipes/393090/>`_\.
+.. function:: isfinite(x)
+
+ Return ``True`` if *x* is neither an infinity nor a NaN, and
+ ``False`` otherwise. (Note that ``0.0`` *is* considered finite.)
+
+
.. function:: isinf(x)
Check if the float *x* is positive or negative infinity.