文件方式实现完整的英文词频统计实例

1.读入待分析的字符串

2.分解提取单词 

3.计数字典

4.排除语法型词汇

5.排序

6.输出TOP(20)

fo=open('text','w')
fo.write('''Counting stars Lately I've been, I've been losing sleep
Dreaming 'bout the things that we could be
But baby I've been, I've been prayin' hard
Said no more counting dollars
We'll be counting stars
Yeah, we'll be counting stars
I see this life Like a swinging vine
Swing my heart across the line
In my face is flashing signs
Seek it out and ye shall find
Old, but I'm not that old''')
fo.close()

fo=open('text','r')
s=fo.read()
fo.close

s=s.lower()
for i in ',.?!-':
    s=s.replace(i,' ')
s=s.replace('\n',' ')
s=s.split(' ')
print(s)

dict={}
exc={'it','be','no','to','or',' '}
keys=set(s)-exc
for i in keys:
    dict[i]=s.count(i)
print(dict)

wc=list(dict.items())
wc.sort(key=lambda x:x[1],reverse=True)
print(wc)

for i in range(20):
    print(wc[i])