如何在两个相关列表中找到最常见的名称

Question

我想从社区寻求帮助。.我在这里有2个相关列表：

names = ['alan_grant', 'alan_grant', 'alan_grant', 'alan_grant', 'alan_grant', 'claire_dearing', 'claire_dearing', 'claire_dearing', 'claire_dearing', 'claire_dearing', 'ellie_sattler', 'ellie_sattler', 'ellie_sattler', 'ellie_sattler', 'ellie_sattler', 'ian_malcolm', 'ian_malcolm', 'ian_malcolm', 'ian_malcolm', 'ian_malcolm', 'john_hammond', 'john_hammond', 'john_hammond', 'john_hammond', 'john_hammond', 'owen_grady', 'owen_grady', 'owen_grady', 'owen_grady', 'owen_grady']
votes = [True, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, True, True, True, True]

票列表是面部识别算法匹配的面部识别算法的结果。然后，我将将每个 true 投票链接到相应的名称，并找到最常见的名称是最终的“获胜者”。

我尝试了两种方法：

characters = {}
for name, vote in list(zip(names, votes)):
    if vote == True:
        characters[name] = characters.get(name, 0) + 1
#print(characters)
print(max(characters, key=characters.get))

输出是'Owen_grady'

from collections import Counter

characters = [name for name, vote in list(zip(names, votes)) if vote == True]
#print(characters)
print(Counter(characters).most_common()[0][0])

输出也为“ Owen_grady”。哪种方式更有效：字典？还是通过计数器列出理解？

我的最终问题是：是否有另一种方法（最有效的）获得结果？我希望输出只是“ owen_grady”

Answer 1

您可以使用 itertools.compress（） /a>要过滤所有 false 条目。 计数器的选项应最有效，只需在 n 参数/library/collections.html#collections.counter.most_common“ rel =” nofollow noreferrer“> .most_common（） 让它返回单个对。

Code:

from itertools import compress
from collections import Counter

names = ['alan_grant', 'alan_grant', 'alan_grant', 'alan_grant', 'alan_grant', 'claire_dearing', 'claire_dearing', 'claire_dearing', 'claire_dearing', 'claire_dearing', 'ellie_sattler', 'ellie_sattler', 'ellie_sattler', 'ellie_sattler', 'ellie_sattler', 'ian_malcolm', 'ian_malcolm', 'ian_malcolm', 'ian_malcolm', 'ian_malcolm', 'john_hammond', 'john_hammond', 'john_hammond', 'john_hammond', 'john_hammond', 'owen_grady', 'owen_grady', 'owen_grady', 'owen_grady', 'owen_grady']
votes = [True, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, True, True, True, True]

most_common = Counter(compress(names, votes)).most_common(1)[0][0]
# Or with some syntax sugar:
# [(most_common, _)] = Counter(compress(names, votes)).most_common(1)

---

Upd. I've made some benchmarks对于这种特殊情况，似乎略微优化的第一种方法表明了更好的性能：

from itertools import compress

names = ['alan_grant', 'alan_grant', 'alan_grant', 'alan_grant', 'alan_grant', 'claire_dearing', 'claire_dearing', 'claire_dearing', 'claire_dearing', 'claire_dearing', 'ellie_sattler', 'ellie_sattler', 'ellie_sattler', 'ellie_sattler', 'ellie_sattler', 'ian_malcolm', 'ian_malcolm', 'ian_malcolm', 'ian_malcolm', 'ian_malcolm', 'john_hammond', 'john_hammond', 'john_hammond', 'john_hammond', 'john_hammond', 'owen_grady', 'owen_grady', 'owen_grady', 'owen_grady', 'owen_grady']
votes = [True, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, True, True, True, True]

characters = list(compress(names, votes))
most_common = max(set(characters), key=characters.count)

Answer 2

您还可以尝试使用 Counter 模块解决方案，除了 zip（）函数：

names = ['alan_grant', 'alan_grant', 'alan_grant', 'alan_grant', 'alan_grant', 'claire_dearing', 'claire_dearing', 'claire_dearing', 'claire_dearing', 'claire_dearing', 'ellie_sattler', 'ellie_sattler', 'ellie_sattler', 'ellie_sattler', 'ellie_sattler', 'ian_malcolm', 'ian_malcolm', 'ian_malcolm', 'ian_malcolm', 'ian_malcolm', 'john_hammond', 'john_hammond', 'john_hammond', 'john_hammond', 'john_hammond', 'owen_grady', 'owen_grady', 'owen_grady', 'owen_grady', 'owen_grady']
votes = [True, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, False, True, True, True, True]

from collections import Counter
import itertools

r = Counter(zip(names, votes))
for i in list(r.keys()):
    if i[1] == False:
        del r[i]
print(r)

output：

Counter({('owen_grady', True): 4, ('alan_grant', True): 1})