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@@ -100,6 +100,48 @@ Number-theoretic and representation functions
<http://code.activestate.com/recipes/393090/>`_\.
+.. function:: gcd(a, b)
+
+ Return the greatest common divisor of the integers *a* and *b*. If either
+ *a* or *b* is nonzero, then the value of ``gcd(a, b)`` is the largest
+ positive integer that divides both *a* and *b*. ``gcd(0, 0)`` returns
+ ``0``.
+
+ .. versionadded:: 3.5
+
+
+.. function:: isclose(a, b, *, rel_tol=1e-09, abs_tol=0.0)
+
+ Return ``True`` if the values *a* and *b* are close to each other and
+ ``False`` otherwise.
+
+ Whether or not two values are considered close is determined according to
+ given absolute and relative tolerances.
+
+ *rel_tol* is the relative tolerance -- it is the maximum allowed difference
+ between *a* and *b*, relative to the larger absolute value of *a* or *b*.
+ For example, to set a tolerance of 5%, pass ``rel_tol=0.05``. The default
+ tolerance is ``1e-09``, which assures that the two values are the same
+ within about 9 decimal digits. *rel_tol* must be greater than zero.
+
+ *abs_tol* is the minimum absolute tolerance -- useful for comparisons near
+ zero. *abs_tol* must be at least zero.
+
+ If no errors occur, the result will be:
+ ``abs(a-b) <= max(rel_tol * max(abs(a), abs(b)), abs_tol)``.
+
+ The IEEE 754 special values of ``NaN``, ``inf``, and ``-inf`` will be
+ handled according to IEEE rules. Specifically, ``NaN`` is not considered
+ close to any other value, including ``NaN``. ``inf`` and ``-inf`` are only
+ considered close to themselves.
+
+ .. versionadded:: 3.5
+
+ .. seealso::
+
+ :pep:`485` -- A function for testing approximate equality
+
+
.. function:: isfinite(x)
Return ``True`` if *x* is neither an infinity nor a NaN, and
@@ -383,6 +425,22 @@ Constants
The mathematical constant e = 2.718281..., to available precision.
+.. data:: inf
+
+ A floating-point positive infinity. (For negative infinity, use
+ ``-math.inf``.) Equivalent to the output of ``float('inf')``.
+
+ .. versionadded:: 3.5
+
+
+.. data:: nan
+
+ A floating-point "not a number" (NaN) value. Equivalent to the output of
+ ``float('nan')``.
+
+ .. versionadded:: 3.5
+
+
.. impl-detail::
The :mod:`math` module consists mostly of thin wrappers around the platform C