import sys #接收执行参数
#!/usr/bin/env python
import sys
print (sys.argv)
例:
>>>python index.py 8000
>>>['index.py','8000']
字符串常用操作:
移动空白: strip()
分割:split
长度:len(obj)
索引:obj[1]
切片:obj[1:],obj[1:10]
元组里面的元素不可修改
元组里面的元素的元素是可以修改的
例:
t1 = (1,2,{'k1':'v1'})
t1 [2]['k1'] = 2
print (t1)
>>>(1,2,{'k1':2})
对于Python,一切事物都是对象,对象基于类创建
str内部功能介绍:
#name = "llluo"
#name = str("llluo") #str类的_init_方法
#print (dir(name))
#print (type(name))
#result = name.__contains__("luo") #luo是否包含在name中
#result = "luo" in name
#result = name.center(20,'*') #空20个*号把名字显示在中间
#result = name.capitalize() #首字母大写
#result = name.count("l") #找l出现了几次
#result = name.count("l",0,2) #在0到2之间找有几个l
#result = name.endswith("o") #是否以o结尾
#result = name.endswith("o",0,4) #判断0到4之间是不是以o结尾
#result = name.find("u") #找出"u"在第几个位置,没有则是-1,有多个则显示第一个
#result = name.index("l") #找出第一个"l"在第几个位置,没有则会报错
#print (result)
#name = "luo {0} as {1}"
#result = name.format("sb","eric") #字符串格式化
#print (result)
#name = "lll\tuo"
#result = name.expandtabs() #把\t换成空格
#print (result)
#li = ['a','m','a','z','i','n','g']
#result = "_".join(li) #以下划线连接字符,没有则是空
#print (result)
#name = "luoisstar"
#result = name.partition("is") #以is为分割点
#print (result)
#name = "luoisstar"
#result = name.replace("s","d",1) #把s都替换成d,后面加了参数,就会转换几个
#print (result)
字典:
dic = {'k1':'v1','k2':'v2'}
dic.get('k1')
dic.get('k2')
dic.get('k3') #因为没有k3,所以返回值为None
dic.get('k3','v3') #如果没有k3,则会生成对应值v3,如果原来k3有值,则会返回原值
dic.keys() #返回键
dic.values() #返回值
dic.items() #返回键值对
dic.pop('k1') #删掉一个键值
dic.popitem() #随机删除一个键值
dic.setdefault('k4',123) #设置默认值,不写则为none
dic.update({'k5':123}) #生成一个新dic字典,原字典删除
例:把列表中大于44的和小于44的数加到字典。有两种方法,请参考
#!/usr/bin/env python
# -*- coding:utf-8 -*-
#Author:luo lingfeng
dic = {}
l1 = []
l2 = []
shu = [1,3,4,5,6,33,22,44,55,99,12,34,54,65,76]
for i in shu:
if i > 44:
l1.append(i)
else:
l2.append(i)
dic['k1'] = l1
dic['k2'] = l2
print dic
事例二:
#!/usr/bin/env python
# -*- coding:utf-8 -*-
#Author:luo lingfeng
dic = {}
shu = [1,3,4,5,6,33,22,44,55,99,12,34,54,65,76]
for i in shu:
if i > 44:
if "k1" in dic.keys():
dic["k1"].append(i)
else:
dic["k1"] = [i,]
else:
if "k2" in dic.keys():
dic["k2"].append(i)
else:
dic["k2"] = [i,]
print dic