>>> import thisThe Zen of Python, by Tim Peters

Beautiful is better than ugly.Explicit is better than implicit.Simple is better than complex.Complex is better than complicated.Flat is better than nested.Sparse is better than dense.Readability counts.Special cases aren't special enough to break the rules.Although practicality beats purity.Errors should never pass silently.Unless explicitly silenced.In the face of ambiguity, refuse the temptation to guess.There should be one-- and preferably only one --obvious way to do it.Although that way may not be obvious at first unless you're Dutch.Now is better than never.Although never is often better than *right* now.If the implementation is hard to explain, it's a bad idea.If the implementation is easy to explain, it may be a good idea.Namespaces are one honking great idea -- let's do more of those!

Old: print "The answer is", 2*2 New: print("The answer is", 2*2)Old: print x, # Trailing comma suppresses newline New: print(x, end=" ") # Appends a space instead of a newlineOld: print # Prints a newlineNew: print() # You must call the function!Old: print >>sys.stderr, "fatal error" New: print("fatal error", file=sys.stderr)Old: print (x, y) # prints repr((x, y))New: print((x, y)) # Not the same as print(x, y)!

1、下载安装包    https://www.python.org/downloads/2、安装python2.7.11    默认安装路径：C:\python273、配置环境变量    【右键计算机】--》【属性】--》【高级系统设置】--》【高级】--》【环境变量】--》【在第二个内容框中找到 变量名为Path 的一行，双击】 --> 【Python安装目录追加到变值值中，用 ； 分割】    如：原来的值;C:\python27，切记前面有分号4、安装python3.5.1    默认安装路径: C:\python355、将python3.5中的执行程序python.exe重命名成python36、配置环境变量    【右键计算机】--》【属性】--》【高级系统设置】--》【高级】--》【环境变量】--》【在第二个内容框中找到 变量名为Path 的一行，双击】 --> 【Python安装目录追加到变值值中，用 ； 分割】     如：原来的值;C:\python35，切记前面有分号7、这样就实现python2.7和python3.5多版本

tomcat@node:~$ pythonPython 3.5.1 (default, Jul 27 2016, 18:07:46) [GCC 5.2.1 20151010] on linuxType "help", "copyright", "credits" or "license" for more information.>>> print("Hello World!")Hello World!

tomcat@node:~$ vim python1.py#!/usr/bin/env python# coding:utf-8print("Hello World!")

tomcat@node:~$ chmod +x python1.py tomcat@node:~$ python python1.py Hello World!

tomcat@node:~$ vim a.py#!/usr/bin/env pythonprint "你好！世界"tomcat@node:~$ python a.py   File "a.py", line 2SyntaxError: Non-ASCII character '\xe4' in file a.py on line 2, but no encoding declared; see http://python.org/dev/peps/pep-0263/ for details

tomcat@node:~$ vi a.py #!/usr/bin/env python# coding:utf-8print "你好！世界"

tomcat@node:~$ python a.py 你好！世界

>>> name = input("please input your name:")please input your name:tomcatxiao>>> print("Hello " + name)Hello tomcatxiao

>>> age = input("please enter your age:")please enter your age:21>>> type(age)<class 'str'>

>>> age1 = input("please enter your age:")>>> age1 = int(age1)>>> type(age1)<class 'int'>

tomcat@node:~$ vi b.py#!/usr/bin/env python# -*- coding: utf-8 -*-

import getpass

# 将用户输入的内容赋值给 pwd变量pwd = getpass.getpass("请输入密码：")

# 打印输入的内容print(pwd)

tomcat@node:~$ python b.py请输入密码：123

>>> name = raw_input("please enter your name:")please enter your name:tomcatxiao>>> print nametomcatxiao

>>> age = raw_input("your age is:")your age is:21>>> print age21

>>> name = input("please input your name:")please input your name:tomcatxiaoTraceback (most recent call last):  File "<stdin>", line 1, in <module>  File "<string>", line 1, in <module>NameError: name 'tomcatxiao' is not defined

>>> age = input("your age is:")your age is:21

>>> myname = "tomcatxiao">>> name = input("please input your name:")please input your name:myname

>>> print nametomcatxiao

print "String %format1 %format2 ..." %(variable1,variable2)  

print("String %format1 %format2 ...." %(variable1,variable2))

print  "String"  + variable1print("String"  + variable1)

tomcat@node:~$ vi c.py#!/usr/bin/env python# -*- coding:utf-8 -*-

name = input("input your name:")age = input("input your age:")job = input("input your job:")

msg = '''Information of %s-------------Name: %sAge : %sJob : %s''' %(name,name,age,job)

print(msg)

tomcat@node:~$ python c.py

#!/usr/bin/env python# -*- coding:utf-8 -*-

name = input("input your name:")age = input("input your age:")job = input("input your job:")

msg = '''Information of %s-------------Name: %sAge : %dJob : %s''' %(name,name,age,job)

print(msg)

input your name:tomcatxiaoinput your age:21input your job:ITTraceback (most recent call last):  File "/home/tomcat/PycharmProjects/s13/day01/dsfg.py", line 15, in <module>    ''' %(name,name,age,job)TypeError: %d format: a number is required, not str

tomcat@node:~$ vi d.py#!/usr/bin/env python# -*- coding: utf-8 -*-

import sys

print(sys.argv)

#输出tomcat@node:~$ python d.py helo world['test.py', 'helo', 'world']  #把执行脚本时传递的参数获取到了

>>> import os>>> os.system("df -h") #调用系统命令

>>> result = os.system("df -h")df: ‘/mnt/hgfs’: Protocol errorFilesystem      Size  Used Avail Use% Mounted onudev            3.9G     0  3.9G   0% /devtmpfs           797M  9.4M  788M   2% /run/dev/sda1       189G   10G  170G   6% /tmpfs           3.9G   16M  3.9G   1% /dev/shmtmpfs           5.0M  4.0K  5.0M   1% /run/locktmpfs           3.9G     0  3.9G   0% /sys/fs/cgroupcgmfs           100K     0  100K   0% /run/cgmanager/fstmpfs           797M   76K  797M   1% /run/user/1000

>>> print(result)256

>>> result = os.popen("df -h").read()

>>> print(result)Filesystem      Size  Used Avail Use% Mounted onudev            3.9G     0  3.9G   0% /devtmpfs           797M  9.4M  788M   2% /run/dev/sda1       189G   10G  170G   6% /tmpfs           3.9G   16M  3.9G   1% /dev/shmtmpfs           5.0M  4.0K  5.0M   1% /run/locktmpfs           3.9G     0  3.9G   0% /sys/fs/cgroupcgmfs           100K     0  100K   0% /run/cgmanager/fstmpfs           797M   76K  797M   1% /run/user/1000

tomcat@node:~$ vi e.py #!/usr/bin/env pythonimport os,sys

os.system(''.join(sys.argv[1:]))

# 执行tomcat@node:~$ python e.py dfdf: ‘/mnt/hgfs’: Protocol errorFilesystem     1K-blocks     Used Available Use% Mounted onudev             4059116        0   4059116   0% /devtmpfs             815812     9596    806216   2% /run/dev/sda1      198036724 10435852 177518160   6% /tmpfs            4079040    15996   4063044   1% /dev/shmtmpfs               5120        4      5116   1% /run/locktmpfs            4079040        0   4079040   0% /sys/fs/cgroupcgmfs                100        0       100   0% /run/cgmanager/fstmpfs             815812       76    815736   1% /run/user/1000

#!/usr/bin/env python # python startup file import sysimport readlineimport rlcompleterimport atexitimport os# tab completion readline.parse_and_bind('tab: complete')# history file histfile = os.path.join(os.environ['HOME'], '.pythonhistory')try:    readline.read_history_file(histfile)except IOError:passatexit.register(readline.write_history_file, histfile)del os, histfile, readline, rlcompleter

tomcat@node:~$ pythonPython 2.7.11 (default, Jul 27 2016, 18:09:58) [GCC 5.2.1 20151010] on linux2Type "help", "copyright", "credits" or "license" for more information.>>> import tab>>> import os>>> os.Display all 238 possibilities? (y or n)os.EX_CANTCREAT             os.fchdir(os.EX_CONFIG                os.fchmod(os.EX_DATAERR               os.fchown(os.EX_IOERR                 os.fdatasync(os.EX_NOHOST                os.fdopen(

>>> import sys>>> sys.path['', '/usr/lib/python2.7', '/usr/lib/python2.7/plat-x86_64-linux-gnu', '/usr/lib/python2.7/lib-tk', '/usr/lib/python2.7/lib-old', '/usr/lib/python2.7/lib-dynload', '/usr/local/lib/python2.7/dist-packages', '/usr/lib/python2.7/dist-packages', '/usr/lib/python2.7/dist-packages/PILcompat', '/usr/lib/python2.7/dist-packages/gtk-2.0', '/usr/lib/python2.7/dist-packages/ubuntu-kylin-sso-client', '/usr/lib/python2.7/dist-packages/ubuntu-sso-client']

if boolean_expression1:    suite1elif boolean_expression2:    suite2else:    else_suite

A = X if Y else Z

if Y:    A = Xelse    A = Z

expression1 if boolean_express else expression2

while boolean_express:    while_suiteelse:    else_suite

示例1：>>> url = 'www.mageedu.com'>>> while url:print(url)       url = url[1:]

示例2：>>> x = 0;y = 100>>> while x < y:print(x)       x += 1

示例3：>>> url = 'www.mageedu.com'>>> while url:print(url)       url = url[:-1]   else:print('game over')

练习1：逐一显示指定列表中的所有元素>>> l1 = [1,2,3,4,5,6]>>> count = 0>>> while l1:print(l1[0])     l1.pop(0)

>>> l1 = [1,2,3,4,5,6]>>> while l1:print(l1[-1])     l1.pop()

>>> l1 = [1,2,3,4,5,6]>>> count = 0>>> while l1 < len(l1):print(l1[count])     count += 1

练习2：求100以内所有偶数之和练习3：逐一显示指定字典的所有键；并于显示结束后说明总键数；>>> d1 = {'x':1,'y':23,'z':78}>>> keylists = d1.keys()>>> while keylists:print(keylists[0])        keylists.pop[0]else:print(len(d1))

练习4：创建一个包含了100以内所有奇数的列表>>> l1 = []>>> x = 1>>> while x < 100:        l1.append(x)        x += 2

练习5：逆序逐一显示一个列表的所有元素练习6：列表l1 = [0,1,2,3,4,5,6],列表l2 = ['Sun','Mon','Tue','Wed','Thu','Fri','Sat'],以第一个列表中的元素为键，以第二个列表中的元素为值生成字典d1

>>> l1 = [0,1,2,3,4,5,6]>>> l2 = ['Sun','Mon','Tue','Wed','Thu','Fri','Sat']>>> d1 = {}>>> count = 0>>> if len(l1) == len(l2):while count < len(l1):        d1[l1[count]] = l2[count]        count += 1

>>> print(d1)

View Code

for expression1 in iterable:    for_suiteelse:    else_suite

T = [(1,2),(3,4),(5,6),(7,8)]for (a,b) in T:　　print(a,b)

>>> S = 'How are you these days?'>>> range(0,len(S),2)[0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22]>>> for i in range(0,len(S),2):       print(S[i])

>>> L = [1,2,3,4,5]>>> for i in range(len(L)):       L[i] += 1>>> L

>>> L1 = [1,2,3,4,5,6,7]>>> L2 = ['a','b','c','d','e','f','g']>>> zip(L1,L2)

>>> keys = [1,2,3,4,5,6,7]>>> vaules = ['Sun','Mon','Tue','Wed','Thu','Fri','Sat']>>> D = {}>>> for (k,v) in zip(keys,values)       D[k] = v>>> D

for循环练习：练习1：逐一分开显示指定字典d1中的所有元素，类似如下;    k1  v1    k2  v2

>>> d1 = {'x':123,'y':321,'z':734}>>> for (k,v) in d1.items():print(k,v)

y 321x 123z 734

练习2：逐一显示列表中l1=['Sun','Mon','Tue','Wed','Thu','Fri','Sat']中索引为奇数的元素;

>>> l1=['Sun','Mon','Tue','Wed','Thu','Fri','Sat']

>>> for i in range(1,len(l1),2):print(l1[i])

练习3：将属于列表l1=['Sun','Mon','Tue','Wed','Thu','Fri','Sat'],但不属于列表l2=['Sun','Mon','Tue','Thu','Sat']的所有元素定义为一个新列表l3;

>>> l1=['Sun','Mon','Tue','Wed','Thu','Fri','Sat'] >>> l2=['Sun','Mon','Tue','Thu','Sat']>>> l3 = []>>> for i in l1:>>>     if i not in l2:>>>         l3.append(i)

练习4：将属于列表namelist=['stu1','stu2','stu3','stu4','stu5','stu6','stu7'],删除列表removelist=['stu3','stu7','stu9'];请将属于removelist列表中的每个元素从namelist中移除(属于removelist,但不属于namelist的忽略即可)

>>> namelist=['stu1','stu2','stu3','stu4','stu5','stu6','stu7']>>> removelist=['stu3','stu7','stu9']>>> for i in removelist:>>>     if i in namelist:>>>         namelist.remove(i)>>> print(namelist)

View Code

#!/usr/bin/env python# -*- coding:utf-8 -*-import getpass

name = 'tom'pwd = 123456count = 0

while True:if count < 3:print("Please enter your name and password !")        username = input("username:")        password = getpass.getpass("password:")

if username == name and password == pwd:print("恭喜你登陆成功！")breakelse:print("登陆失败！用户名或者密码错误")else:print("你已经输错3次,正在退出....")break

    count += 1

#!/usr/bin/env python# -*- coding:utf-8 -*-

age = 22count = 0

for i in range(10):if count < 3:        a = int(input("please input num:"))if a == age:print("恭喜你,答对了")breakelif a > age:print("你猜的数字大了")else:print("你猜的数字小了")else:        b = input("你太笨了,这都猜不对,你继续玩吗？(yes or not):")if b == 'yes':            count = 0continueelse:print("Bye!下次再玩")

    count += 1