方法一：用字典方法统计序列中元素的出现频度
ange(30)] ##创建一个随机数序列 data Out[57]: [5, 13, 0, 1, 17, 8, 7, 3, 19, 15, 19, 15, 11, 17, 16, 12, 9, 17, 4, 0, 17, 4, 1, 14, 2, 2, 6, 12, 3, 2] c = dict.fromkeys(data,0) ##创建一个字典，用随机数序列做键，默认初始值为0 c Out[59]: {0: 0, 1: 0, 2: 0, 3: 0, 4: 0, 5: 0, 6: 0, 7: 0, 8: 0, 9: 0, 11: 0, 12: 0, 13: 0, 14: 0, 15: 0, 16: 0, 17: 0, 19: 0} for x in data: ##遍历建，如果键相同，就加1.就可以得出序列中元素出现的次数 c[x] +=1 c Out[61]: {0: 2, 1: 2, 2: 3, 3: 2, 4: 2, 5: 1, 6: 1, 7: 1, 8: 1, 9: 1, 11: 1, 12: 2, 13: 1, 14: 1, 15: 2, 16: 1, 17: 4, 19: 2} 方法二：使用collection.Counter对象Counter是一个简单的计数器，例如，统计字符出现的个数：
代码接方法一
from collections import Counter c2 = Counter(data) c2 Out[64]: Counter({0: 2, 1: 2, 2: 3, 3: 2, 4: 2, 5: 1, 6: 1, 7: 1, 8: 1, 9: 1, 11: 1, 12: 2, 13: 1, 14: 1, 15: 2, 16: 1, 17: 4, 19: 2}) c2.most_common(3)##most_common 方法筛选频率最高的3个 Out[65]: [(17, 4), (2, 3), (0, 2)]
