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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Python代码
import string, os, sys
dir = '/var'
print '----------- no sub dir'
files = os.listdir(dir)
for f in files:
......
16.1. select — Waiting for I/O completion¶
This module provides access to the select and poll functions available in most operating systems, epoll available on Linux 2.5+ and kqueue available on most BSD. Note that on Windows, it only works for sockets; on other operating systems, it al ......
前一段时间试着用这三种语言简单的写了关于文件拷贝的程序,发现c#和python的api惊人的相似,对于文件的操作这两种语言非常的方便。都没有加异常的处理
C#源代码:
public static void CopyFile(string source, string destination)
& ......
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 ......
写了几个有关operaminimod的python小程序
firefox->opm书签转换
import re
def pipeiwangzhi(a):
s=[]
pp= re.compile(r'<DT><A HREF="(.*)" ADD_DATE=(.*>)(.*)</A>')
m=pp.search(a)
s1=[]
  ......