diff --git a/Doc/library/collections.rst b/Doc/library/collections.rst index 723c9da7be8..94166ec6c75 100644 --- a/Doc/library/collections.rst +++ b/Doc/library/collections.rst @@ -313,6 +313,16 @@ For example:: .. versionadded:: 3.2 + .. method:: total() + + Compute the sum of the counts. + + >>> c = Counter(a=10, b=5, c=0) + >>> c.total() + 15 + + .. versionadded:: 3.10 + The usual dictionary methods are available for :class:`Counter` objects except for two which work differently for counters. @@ -342,7 +352,7 @@ All of those tests treat missing elements as having zero counts so that Common patterns for working with :class:`Counter` objects:: - sum(c.values()) # total of all counts + c.total() # total of all counts c.clear() # reset all counts list(c) # list unique elements set(c) # convert to a set diff --git a/Lib/collections/__init__.py b/Lib/collections/__init__.py index 89c73bbf2c1..bae0805d668 100644 --- a/Lib/collections/__init__.py +++ b/Lib/collections/__init__.py @@ -581,6 +581,10 @@ class Counter(dict): # Needed so that self[missing_item] does not raise KeyError return 0 + def total(self): + 'Sum of the counts' + return sum(self.values()) + def most_common(self, n=None): '''List the n most common elements and their counts from the most common to the least. If n is None, then list all element counts. diff --git a/Lib/test/test_collections.py b/Lib/test/test_collections.py index 2ba1a19ead9..f98048b34a7 100644 --- a/Lib/test/test_collections.py +++ b/Lib/test/test_collections.py @@ -2066,6 +2066,10 @@ class TestCounter(unittest.TestCase): self.assertRaises(TypeError, Counter, (), ()) self.assertRaises(TypeError, Counter.__init__) + def test_total(self): + c = Counter(a=10, b=5, c=0) + self.assertEqual(c.total(), 15) + def test_order_preservation(self): # Input order dictates items() order self.assertEqual(list(Counter('abracadabra').items()), diff --git a/Misc/NEWS.d/next/Library/2021-05-02-19-17-20.bpo-25478.AwlwdA.rst b/Misc/NEWS.d/next/Library/2021-05-02-19-17-20.bpo-25478.AwlwdA.rst new file mode 100644 index 00000000000..81d2724726d --- /dev/null +++ b/Misc/NEWS.d/next/Library/2021-05-02-19-17-20.bpo-25478.AwlwdA.rst @@ -0,0 +1,2 @@ +Added a *total()* method to collections.Counter() to compute the sum of the +counts.