在Python中查找字符串中每个单词的频率 _单词频率

本文概述

Python3
Python3

编写python代码以查找给定字符串中每个单词的频率。
例子：

Input :str[] = "Apple Mango Orange Mango Guava Guava Mango" Output : frequency of Apple is : 1 frequency of Mango is : 3 frequency of Orange is : 1 frequency of Guava is : 2Input :str = "Train Bus Bus Train Taxi Aeroplane Taxi Bus" Output : frequency of Train is : 2 frequency of Bus is : 3 frequency of Taxi is : 2 frequency of Aeroplane is : 1

使用list()的方法1：
1.通过在python中使用带分隔符的分隔功能(即string.split())将字符串分成包含单词的列表。

Note: string_name.split(separator) method is used to split the string by specified separator(delimiter) into the list. If delimiter is not provided then white space is a separator. For example: CODE: str='This is my book' str.split() OUTPUT : ['This', 'is', 'my', 'book']

2.初始化一个新的空列表。
3.现在, 如果新列表中不存在该单词, 则将该单词附加到先前字符串中的新列表中。
4.遍历新列表, 并使用计数函数(即string.count(newstring [iteration]))在每次迭代中查找单词的出现频率。

Note: string_name.count(substring) is used to find no. of occurrence of substring in a given string.For example: CODE: str='Apple Mango Apple' str.count('Apple') str2='Apple' str.count(str2) OUTPUT : 2 2

Python3

# Python code to find frequency of each word def freq( str ):# break the string into list of words str = str .split() str2 = []# loop till string values present in list str for i in str :# checking for the duplicacy if i not in str2:# insert value in str2 str2.append(i) for i in range ( 0 , len (str2)):# count the frequency of each word(present # in str2) in str and print print ( 'Frequency of' , str2[i], 'is :' , str .count(str2[i]))def main(): str = 'apple mango apple orange orange apple guava mango mango' freq( str )if __name__ = = "__main__" : main()# call main function

输出如下：

Frequency ofappleis :3 Frequency ofmangois :3 Frequency oforangeis :2 Frequency ofguavais :1

使用set()的方法2：
1.通过在Python中使用带分隔符的分隔功能(即string.split())将字符串分成包含单词的列表。
2.采用set()删除重复项并给出一组唯一单词的方法
3.遍历set并使用count函数(即string.count(newstring [iteration]))来查找每次迭代中单词的出现频率。
Python3

# Python3 code to find frequency of each word # function for calculating the frequency def freq( str ):# break the string into list of words str_list = str .split()# gives set of unique words unique_words = set (str_list)for words in unique_words : print ( 'Frequency of ' , words , 'is :' , str_list.count(words))# driver code if __name__ = = "__main__" :str = 'apple mango apple orange orange apple guava mango mango'# calling the freq function freq( str )

输出如下：

Frequency ofappleis :3 Frequency ofmangois :3 Frequency oforangeis :2 Frequency ofguavais :1

方法3(使用字典)

# Find frequency of each word in a string in Python # using dictionary.def count(elements): # check if each word has '.' at its last. If so then ignore '.' if elements[ - 1 ] = = '.' : elements = elements[ 0 : len (elements) - 1 ]# if there exists a key as "elements" then simply # increase its value. if elements in dictionary: dictionary[elements] + = 1# if the dictionary does not have the key as "elements" # then create a key "elements" and assign its value to 1. else : dictionary.update({elements: 1 })# driver input to check the program.Sentence = "Apple Mango Orange Mango Guava Guava Mango"# Declare a dictionary dictionary = {}# split all the word of the string. lst = Sentence.split()# take each word from lst and pass it to the method count. for elements in lst: count(elements)# print the keys and its corresponding values. for allKeys in dictionary: print ( "Frequency of " , allKeys, end = " " ) print ( ":" , end = " " ) print (dictionary[allKeys], end = " " ) print () # This code is contributed by Ronit Shrivastava.

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