Python 中可以有多种实现方法,但只有一种是比较优雅的,那就是采用原生 Python 的实现–dict数据类型。 代码如下所示: # count the number of word occurrences in a piece of text text = "I need to count the number of word occurrences in a piece of text. How could I do that? " \ "Python pr...
"\"Python provides us with multiple ways to do the same thing. But only one way I find beautiful."word_count_dict={}forwintext.split(" "):ifwinword_count_dict:word_count_dict[w]+=1else:word_count_dict[w]=1 这里还可以应用defaultdict来减少代码行数: 代码语言:javascript 复制 from collec...
https://towardsdatascience.com/python-pro-tip-start-using-python-defaultdict-and-counter-in-place-of-dictionary-d1922513f747 关于字典的介绍,也可以查看我之前写的Python基础入门_2基础语法和变量类型。 本文目录: Counter 和 defaultdict 为何要用 defaultdict 呢? defaultdict 的定义和使用 Counter 的定义和使...
items（）方法返回视图对象。视图对象包含字典的键值对，作为列表中的元组。字典中的items方法返回dict_ite...
TheZenofPython, byTimPetersBeautifulisbetter than ugly.Explicitisbetter than implicit.Simpleisbetter than complex.Complexisbetter than complicated.Flatisbetter than nested.Sparseisbetter than dense.Readabilitycounts.Specialcases aren't special enough tobreakthe rules.Althoughpracticality beats purity.Errorssh...
# A Python program to show different ways to create# CounterfromcollectionsimportCounter# With sequence of itemsprint(Counter(['B','B','A','B','C','A','B','B','A','C']))# with dictionaryprint(Counter({'A':3,'B':5,'C':2}))# with keyword argumentsprint(Counter(A=3,B=...
# Dictionary as argument to Counter word_count_dict = {'Dog': 2, 'Cat': 1, 'Horse': 1} counter = Counter(word_count_dict) print(counter) # Counter({'Dog': 2, 'Cat': 1, 'Horse': 1}) As I mentioned above, we can use non-numeric data for count values too, but that will...
Python 中的 collections 模块是用于存储列表、字典、元组以及集等数据集合的容器。这些容器嵌入在 Python 中,可以实现开箱即用。collections 模块提供了额外的高性能数据类型,它们可以优化代码,让一些任务变得更加简洁。 Counter Counter 是 dictionary 对象的子类。collections 模块中的 Counter() 函数会接收一个诸如 list...
allowed to contain zero and negative counts. Source can be an iterable, a dictionary, or another Counter instance. >>> c = Counter('which') >>> c.subtract('witch') # subtract elements from another iterable >>> c.subtract(Counter('watch')) # subtract elements from another counter ...
allowed to contain zero and negative counts. Source can be an iterable, a dictionary, or another Counter instance. 啥意思,就是更新你的Counter对象,怎么更新,基于你传入的参数,它给你做减法,参数是可迭代对象,字典,或者另一个Counter 看官方的例子 ...