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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对数据库的操作基本分为三步：
连接数据库
根据需要执行SQL语句，接受返回值
关闭连接
我们正常的数据库应该都离不开这三步，下来说说如何使用python中的MySQLdb模块进行这些操作：
首先，我们需要把MySQLdb引入到程序中
import MySQLdb
然后开始数据库操作
1.数据库连接
conn = MySQLdb. ......
#
-*- encoding: gb2312 -*-
import
os, sys, string
import
MySQLdb
#
连接数据库
try
:
conn
=
MySQLdb.connect(host
=
'
localhost
'
,user
=
'
root
'
,passwd
=
'
xxxx
'
,db
=
'
test1
'
)
except
Exception, e:
print
e
sys.exit()
......
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 ......
multiprocessing — Process-based “threading” interface
Introduction
multiprocessing is a package that supports spawning processes using an API similar to the threading module. The multiprocessing package offers both local and remote concurrency, effectively side-stepping the Glo ......
1.常用方法，不带参数
def decator(func):
def inner_func(*args):
args = (i * 2 for i in args)
return func(*args)
return inner_func
@decator
def add(a, ......
