Python 有权重的随机选择, Weighted Random Choice
import random def windex(lst):
'''an attempt to make a random.choose() function that makes weighted choices
accepts a list of tuples with the item and probability as a pair'''
wtotal = sum([x[1] for x in lst])
n = random.uniform(0, wtotal)
for item, weight in lst:
if n < weight:
break
n = n - weight
return item
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def Start(self):
if (self.conn == None) or (self.conn.State == 1):
self.conn = win32com.client.Dispatch(r'ADODB.Connection')
&n ......
python 中的re 模块
正则表达式
就个人而言,主要用它来做一些复杂字符串分析,提取想要的信息
学习原则:够用就行,需要的时候在深入
现总结如下:
正则表达式中特殊的符号:
“.” 表任意字符
“^ ” 表string起始
“$” 表string 结束
“*” “+” & ......
闲来无事, 玩玩python...
是采用有道翻译, 然后抓取网页的.
import re, urllib
url="http://dict.youdao.com/search?le=eng&q="
print ("input q to exit")
while 1:
word = raw_input(">>>")
if word=="q":
exit()
else:
word = word.replace(' ', '+')
url += word
u ......
8.8. queue — A synchronized queue class¶
queue -- 一个同步队列类
The queue module implements multi-producer, multi-consumer queues. It is especially useful in threaded programming when information must be exchanged safely between multiple threads. The Queue class in this module implemen ......