python学习笔记Day4

1、set集合

    set集合是一种无序且不重复的集合

   添加功能：

s1 = set()
s1.add("wang")
print(s1)

difference功能（从当前集合里找出不同的元素并生成一个新的集合）：

s1 = set(["wang","pan","lai"])
s2 = s1.difference(["wang","pan"])
print(s2)

结果：{'lai'}

difference_update(从当前集合里去掉重复的元素，不生成新的集合)：

s1 = set(["wang","pan","lai"])
s1.difference_update(["pan","lai"])
print(s1)

结果：{'wang'}

1、队列
单项队列(queue)：先进先出
双向队列（collections）：两边都可以进和取

2、字典{}、元组（）、列表[]

 

3、深copy（copy.deepcopy（））和浅copy（copy.copy()） 
  对于数字和字符串来说，两者的结果内存地址是一样的

4、函数


函数里的try语句：

 

# -*- coding:utf-8 -*-
# Author: cslzy
# Email: lizhenyang_2008@163.com
# Description:send something to someone.
# Date: 20151104 18:33:08
import smtplib
from email.mime.text import MIMEText as mt

def mail(user):
    ret = 'ture'
    try:
        msg = MIMEText('你好！','plaon','utf-8')
        msg['From'] = formataddr(['王盼','wangpan0810@126.com'])
        msg['To'] = formataddr(['王盼','1471333927@qq.com'])
        msg['Subject'] = '主题'

        server = smtplib.SMTP('smtp.126.com',25)
        server.login('wangpan0810@126.com','密码')
        server.sendmail('wangpan0810@126.com',[user,],msg.as_string())
        server.quit()
    except Exception:
        ret = 'false'
    return ret
ret = mail('1471333927@qq.com')
print(ret)

   默认参数必须写在后面。

动态参数（*：元组，**字典）：

def han(*arg,**karg):
    print(arg,type(arg))
    print(karg,type(karg))

han(7,89,3,62,n1=78,n2=88)

def han(*arg,**karg):
    print(arg,type(arg))
    print(karg,type(karg))

l1 = [7,89,3,62]
l2 = {'n1':78,'n2':88}
han(*l1,**l2)

#l1 = '{0} is {1}'
l1 = '{name} is {role}'
n1 = {'name':'ren','role':'dashen'}
#l2 = l1.format('ren','dashen')
#l2 = l1.format(name='ren',role='dashen')
l2 = l1.format(**n1)
print(l2)

简单函数lambda表达式：

 

Python的编码注释# -*- coding:utf-8 -*-

如果要在python2的py文件里面写中文，则必须要添加一行声明文件编码的注释，否则python2会默认使用ASCII编码。

参考：http://blog.csdn.net/arbel/article/details/7957782

python内置函数:
http://www.runoob.com/python/python-built-in-functions.html