Issue #11888: Add log2 function to math module. Patch written by Mark

Dickinson.

2 files changed, 36 insertions, 16 deletions

diff --git a/Doc/library/math.rst b/Doc/library/math.rst
index 98c5b33..8254d3f 100644
--- a/Doc/library/math.rst
+++ b/Doc/library/math.rst
@@ -184,6 +184,13 @@ Power and logarithmic functions
    result is calculated in a way which is accurate for *x* near zero.
 
 
+.. function:: log2(x)
+
+   Return the base-2 logarithm of *x*.
+
+   .. versionadded:: 3.3
+
+
 .. function:: log10(x)
 
    Return the base-10 logarithm of *x*.  This is usually more accurate
diff --git a/Doc/whatsnew/3.3.rst b/Doc/whatsnew/3.3.rst
index 37f96ce..e657af2 100644
--- a/Doc/whatsnew/3.3.rst
+++ b/Doc/whatsnew/3.3.rst
@@ -76,25 +76,15 @@ New module: :mod:`faulthandler`.
  * :envvar:`PYTHONFAULTHANDLER`
  * :option:`-X` ``faulthandler``
 
-os
---
 
-* The :mod:`os` module has a new :func:`~os.sendfile` function which provides
-  an efficent "zero-copy" way for copying data from one file (or socket)
-  descriptor to another. The phrase "zero-copy" refers to the fact that all of
-  the copying of data between the two descriptors is done entirely by the
-  kernel, with no copying of data into userspace buffers. :func:`~os.sendfile`
-  can be used to efficiently copy data from a file on disk to a network socket,
-  e.g. for downloading a file.
+math
+----
 
-  (Patch submitted by Ross Lagerwall and Giampaolo Rodolà in :issue:`10882`.)
+The :mod:`math` module has a new function:
 
-* The :mod:`os` module has two new functions: :func:`~os.getpriority` and
-  :func:`~os.setpriority`. They can be used to get or set process
-  niceness/priority in a fashion similar to :func:`os.nice` but extended to all
-  processes instead of just the current one.
+  * :func:`~math.log2`: return the base-2 logarithm of *x*
+    (Written by Mark Dickinson in :issue:`11888`).
 
-  (Patch submitted by Giampaolo Rodolà in :issue:`10784`.)
 
 nntplib
 -------
@@ -112,6 +102,28 @@ connection when done::
 
 (Contributed by Giampaolo Rodolà in :issue:`9795`)
 
+
+os
+--
+
+* The :mod:`os` module has a new :func:`~os.sendfile` function which provides
+  an efficent "zero-copy" way for copying data from one file (or socket)
+  descriptor to another. The phrase "zero-copy" refers to the fact that all of
+  the copying of data between the two descriptors is done entirely by the
+  kernel, with no copying of data into userspace buffers. :func:`~os.sendfile`
+  can be used to efficiently copy data from a file on disk to a network socket,
+  e.g. for downloading a file.
+
+  (Patch submitted by Ross Lagerwall and Giampaolo Rodolà in :issue:`10882`.)
+
+* The :mod:`os` module has two new functions: :func:`~os.getpriority` and
+  :func:`~os.setpriority`. They can be used to get or set process
+  niceness/priority in a fashion similar to :func:`os.nice` but extended to all
+  processes instead of just the current one.
+
+  (Patch submitted by Giampaolo Rodolà in :issue:`10784`.)
+
+
 sys
 ---
 
@@ -120,10 +132,11 @@ sys
 
   (:issue:`11223`)
 
+
 signal
 ------
 
-* The :mod:`signal` module has a new functions:
+* The :mod:`signal` module has new functions:
 
   * :func:`~signal.pthread_sigmask`: fetch and/or change the signal mask of the
     calling thread (Contributed by Jean-Paul Calderone in :issue:`8407`) ;