如何找到一个字aftr排序inthon的频率

Question

我有一个txt文件，从中我想要计算每个
字的频率，之后，我想排序列表和排序后我想要
打印频率按相关词汇从大到小排序。我
编写Python代码，但我不记得如何做到这一点。代码是

frequency = [] 
file = open("C:/Python26/rzlt.txt"); 
contents=file.read(); 
tokens = nltk.word_tokenize(contents); 
f=open("frequencies.txt",'w') 
f2=open("count.txt",'w') 
for t in tokens: 
    freq = str(tokens.count(t)) 
    frequency.append(freq) 
    f.write(t+"\t"+freq) 
frequency.sort(reverse=True) 
for t in tokens: 
    f2.write(t+"\t"+ frequency(t)) 
f.close() 
f2.close() 

Answer 1

with open() as .. :自动关闭文件。 collections.Counter()统计列表中的所有单词。

最后sorted()按降序排列Counter()对象。

import collections 

with open('my_text_file.txt', 'r') as f: 

    f_as_lst = f.read().split() 
    c = collections.Counter(f_as_lst) 

# Creates a list of tuples with values and keys swapped 
freq_lst = [(v, k) for k, v in c.items()] 
# Sorts list by frequency 
freq_lst = sorted(freq_lst, key=lambda item: item[0]) 

print freq_lst 

---

如果你不能使用collections.Counter()，可以使用下面的函数来替代它：

def my_counter(list_of_strings):  
    dct = {} 

    for string in list_of_strings: 
     if string not in dct: 
      dct.update({string: 1}) 
     else: 
      dct[string] += 1 

    return dct 

Answer 2

尝试这样的：使用计数器

import nltk 
from collections import Counter 
file = open("C:/Python26/rzlt.txt"); 
contents = file.read(); 
tokens = nltk.word_tokenize(contents); 
words = map(str.isalnum, tokens) 
frequency = Counter(words) 

for x, y in sorted(frequency.items(), key=lambda x:x[1]): 
    print x, y 

Answer 3

Try This, I had used collections for getting the count of the each word,
and for displaying it in ascending ordered i used sorted with parameter
reverse=True 

import collections  ## import the collection module 
file = open("filename.txt")  ## open the file which need to be sorted
list = []      ## Create the empty list
print "sorted data : "   
print "==============================================="
for data in file:    ## Iterate the data file 
    list.append(data.strip())
print "\n".join(sorted(list)) ## Print each read line on next line
count = collections.Counter(list) ## Get the count of the each word 
print "==============================================="
print "Count of each word is:"
for data in sorted(count, reverse=True):  ## Iterate the file in ascending order
    print '%s : %d' % (data, count[data]) ## Print the read file in ascending order