Issue #9165: Add math.isfinite and cmath.isfinite.
diff --git a/Doc/library/cmath.rst b/Doc/library/cmath.rst
index 14b909b..ae94039 100644
--- a/Doc/library/cmath.rst
+++ b/Doc/library/cmath.rst
@@ -187,6 +187,12 @@
Classification functions
------------------------
+.. function:: isfinite(x)
+
+ Return ``True`` if both the real and imaginary parts of *x* are finite,
+ and ``False`` otherwise.
+
+
.. function:: isinf(x)
Return *True* if the real or the imaginary part of x is positive
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.