python统计序列中元素出现的频率

随机序列，找出出现次数最高的3个元素，输出出现次数

from random import randint

data = [randint(0, 20) for _ in xrange(30)]
print data

# data作为键， 0作为值
c = dict.fromkeys(data, 0)

for x in data:
    c[x] += 1
print c

"""
 使用collections.Counter对象
 将序列传入Counter的构造器，得到对象是元素频率的字典
"""
from collections import Counter

c2 = Counter(data)
print c2
# 出现频率虽高的3个
c2 = c2.most_common(3)
print c2

英文文章进行词频统计，找出现次数最高的10个单词

"""
 正则表达式：非字母进行分割
"""
import re
text = open('文件.txt').read()
aList = re.split('\W+', text)
c3 = Counter(aList)
print c3
print c3.most_common(10)