Issue 7447: Improve docs for sum().

This commit is contained in:
Raymond Hettinger 2010-10-31 21:28:53 +00:00
parent 490986308e
commit 15c2cec4fd

View file

@ -1227,10 +1227,13 @@ available. They are listed here in alphabetical order.
Sums *start* and the items of an *iterable* from left to right and returns the
total. *start* defaults to ``0``. The *iterable*'s items are normally numbers,
and are not allowed to be strings. The fast, correct way to concatenate a
sequence of strings is by calling ``''.join(sequence)``. Note that
``sum(range(n), m)`` is equivalent to ``reduce(operator.add, range(n), m)``
To add floating point values with extended precision, see :func:`math.fsum`\.
and the start value is not allowed to be a string.
For some use cases, there a good alternatives to :func:`sum`.
The preferred, fast way to concatenate a sequence of strings is by calling
``''.join(sequence)``. To add floating point values with extended precision,
see :func:`math.fsum`\. To concatenate a series of iterables, consider using
:func:`itertools.chain`.
.. versionadded:: 2.3