From 19746cb322095a82f9792bc6806ba66dcc886973 Mon Sep 17 00:00:00 2001 From: Mark Dickinson Date: Fri, 30 Jul 2010 13:16:07 +0000 Subject: [PATCH] Merged revisions 83277 via svnmerge from svn+ssh://pythondev@svn.python.org/python/branches/py3k ........ r83277 | mark.dickinson | 2010-07-30 14:13:02 +0100 (Fri, 30 Jul 2010) | 1 line Add note about surprising behaviour from round function. ........ --- Doc/library/functions.rst | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/Doc/library/functions.rst b/Doc/library/functions.rst index e54faaee419..f5ff69ede95 100644 --- a/Doc/library/functions.rst +++ b/Doc/library/functions.rst @@ -1095,6 +1095,14 @@ available. They are listed here in alphabetical order. example, ``round(0.5)`` is ``1.0`` and ``round(-0.5)`` is ``-1.0``). + .. note:: + + The behavior of :func:`round` for floats can be surprising: for example, + ``round(2.675, 2)`` gives ``2.67`` instead of the expected ``2.68``. + This is not a bug: it's a result of the fact that most decimal fractions + can't be represented exactly as a float. See :ref:`tut-fp-issues` for + more information. + .. function:: set([iterable]) :noindex: