From f909202c11e0a304486c9fb71458e19a598d10c0 Mon Sep 17 00:00:00 2001 From: Raymond Hettinger Date: Mon, 29 Jun 2009 18:30:43 +0000 Subject: [PATCH] Issue 6370: Performance issue with collections.Counter(). --- Lib/collections.py | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/Lib/collections.py b/Lib/collections.py index bd5d3e86f9..f255919f0f 100644 --- a/Lib/collections.py +++ b/Lib/collections.py @@ -421,13 +421,15 @@ class Counter(dict): if iterable is not None: if isinstance(iterable, Mapping): if self: + self_get = self.get for elem, count in iterable.items(): - self[elem] += count + self[elem] = count + self_get(elem, 0) else: dict.update(self, iterable) # fast path when counter is empty else: + self_get = self.get for elem in iterable: - self[elem] += 1 + self[elem] = 1 + self_get(elem, 0) if kwds: self.update(kwds) -- 2.50.1