Python | 查找字符串中每个字符的频率

Given a string and we have to find the frequency of each character of the string in Python.

给定一个字符串，我们必须在Python中查找该字符串的每个字符的频率。

Example:

例：

    Input: 
"hello"
Output:
{'o': 1, 'h': 1, 'e': 1, 'l': 2}

Python code to find frequency of the characters

Python代码查找字符频率

# Python program to find the frequency of 
# each character in a string
# function definition
# it accepts a string and returns a dictionary 
# which contains the frequency of each chacater
def frequency(text):
# converting string to lowercase
text = text.lower()
# dictionary declaration
dict = {}
# traversing the characters
for char in text:
keys = dict.keys()
if char in keys:
dict[char] += 1
else:
dict[char] = 1
return dict
# main code
if __name__ == '__main__':
# inputting the string and printing the frequency
# of all characters
user_input = str(input("Enter a string: "))
print(frequency(user_input))
user_input = str(input("Enter another string: "))
print(frequency(user_input))

Output

输出量

Enter a string: Hello
{'o': 1, 'h': 1, 'e': 1, 'l': 2}
Enter another string: aabbcc bb ee dd
{'a': 2, 'd': 2, 'e': 2, 'b': 4, 'c': 2, ' ': 3}

Explanation:

说明：

In the above example main () function execute first then it'll ask the user to enter the string as input. After that frequency() will be called. user_input contains the string entered by the user. user_input is now passed through the function. The function turns all the characters into the lowercase after that using for loop the frequencies of all the characters will be counted. And then, an empty dictionary will be created where characters will be stored as the values of the characters and frequencies will be stored as the keys of the dictionary.

在上面的示例中，main()函数首先执行，然后要求用户输入字符串作为输入。之后， frequency()将被调用。 user_input包含用户输入的字符串。现在， user_input通过函数传递。在使用for循环之后，该功能会将所有字符转换为小写字母，然后将对所有字符的频率进行计数。然后，将创建一个空字典，在其中将字符存储为字符的值，而频率将存储为字典的键。