自学python
print(）格式输入
print(format(val,format_modifier))
val: 值
format_modifier 格式学
print(format(12.34567,'6.2f'))
6 输入占位
3 精度 小数点 后几位
百分号 格式化输出
print(format(0.346,'.2%'))
输入语句
re=raw_input(prompt)
prompt 提示字符
re 为返回值
>>> age = raw_input('your age : ')
your age : 23
>>> print(age)
23
>>> age=int(age)
>>> age=int(raw_input('plz input your age'))
plz input your age 23
>>> print age
23
>>> type(age)
<type 'int'>
age =int（age） 字符串转换成整型
int 整型
float 浮点型数据
id 函数
>>> print x 12 >>> id(x) 38687280 >>> print x 12 >>> x=13 >>> print x 13 >>> id(x) 38687256 >>> x =12 >>> print x 12 >>> id(x) 38687280 >>> y=13 >>> print y 13 >>> id(y) 38687256 >>>指向 内存 一样
python 变量 不是内容变 指向内存单元的变
>>> x=12 >>> y=12.5 >>> z='www.baidu.com' >>> print x 12 >>> print y 12.5 >>> print z www.baidu.com >>> type(x) <type 'int'> >>> type(y) <type 'float'> >>> type(z) <type 'str'>
python 函数
字符函数库
>>> s = 'baidu'
>>> s.islower()
True
小写函数
替换函数
>>> s4 ='abadsadsadasbab111111111'
>>> s4.replace('ab','AB')
'ABadsadsadasbAB111111111'
默认字符库
import math
引入数学函数库
>>> import math
>>> val=math.sin(3.14/6)
>>> print val
0.499770102643
>>> math.pi
3.1415926535897931
>>> val=math.sin(math.pi /6)
>>> print val
0.5
>>> 3*3*3*3
81
>>> math.pow(3,4)
81.0
pow函数 3的4次方
>>> 3*3*3*3*3*3*3
2187
>>> math.pow(3,7)
2187.0
>>> 3**7
2187
import os
加载操作系统模块
>>> import os
>>> os.getcwd()
'/root'
>>> import socket
>>> baiduip=socket.gethostbyname('www.baidu.com')
>>> print baiduip
115.239.210.26
获得某主机ip地址 网络库
输入quit（）
第三方提供的函数库
httplib2
[root@ceshi ~]# yum install python-setuptools Loaded plugins: fastestmirror Loading mirror speeds from cached hostfile * base: mirrors.163.com * extras: mirrors.grandcloud.cn * updates: mirrors.grandcloud.cn Setting up Install Process Resolving Dependencies --> Running transaction check ---> Package python-setuptools.noarch 0:0.6.10-3.el6 set to be updated --> Finished Dependency Resolution Dependencies Resolved ================================================================================ Package Arch Version Repository Size ================================================================================ Installing: python-setuptools noarch 0.6.10-3.el6 base 336 k Transaction Summary ================================================================================ Install 1 Package(s) Upgrade 0 Package(s) Total download size: 336 k Installed size: 1.5 M Is this ok [y/N]: y Downloading Packages: python-setuptools-0.6.10-3.el6.noarch.rpm | 336 kB 00:00 Running rpm_check_debug Running Transaction Test Transaction Test Succeeded Running Transaction Installing : python-setuptools-0.6.10-3.el6.noarch 1/1 Installed: python-setuptools.noarch 0:0.6.10-3.el6 Complete!
import urllib
import webbrowser
url='http://www.163.com'
content=urllib.urlopen(url).read()
open('163.com.html','w').write(content)
webbrowser.open_new_tab('163.com.html')
[root@ceshi ~]# easy_install httplib2 Searching for httplib2 Reading http://pypi.python.org/simple/httplib2/ Reading http://code.google.com/p/httplib2/ Best match: httplib2 0.8 Downloading http://httplib2.googlecode.com/files/httplib2-0.8.zip Processing httplib2-0.8.zip Running httplib2-0.8/setup.py -q bdist_egg --dist-dir /tmp/easy_install-jLdE50/httplib2-0.8/egg-dist-tmp-jb2a6G zip_safe flag not set; analyzing archive contents... httplib2.__init__: module references __file__ Adding httplib2 0.8 to easy-install.pth file Installed /usr/lib/python2.6/site-packages/httplib2-0.8-py2.6.egg Processing dependencies for httplib2 Finished processing dependencies for httplib2
安装第三方函数库
或者使用
先yum一下python-pip包
然后用pip install安装好了
进行测试
[root@ceshi ~]# python Python 2.6.6 (r266:84292, Nov 22 2013, 12:16:22) [GCC 4.4.7 20120313 (Red Hat 4.4.7-4)] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> import httplib2 >>>
[root@ceshi ~]# python 1.py
Entry programme
hello the cruel world!
www.baidu.com
Leave programme
[root@ceshi ~]# vi 1.py
#!/usr/bin/python
def test_a():
print 'hello the cruel world!'
print 'www.baidu.com'
print 'Entry programme'
test_a()
print 'Leave programme'
自定义函数 注意要有冒号和缩进
[root@ceshi ~]# vi 1.py
#!/usr/bin/python
def test_a():
print 'hello the cruel world!'
print 'www.baidu.com'
def test_b(va11,va12):
print va11,
print va12
print 'Entry programme'
test_a()
test_b(12,13)
test_b('www.baidu.com','python')
test_a()
print 'Leave programme'
返回值 return
#!/usr/bin/python
def test_a():
print 'hello the cruel world!'
print 'www.baidu.com'
def test_b(va11,va12):
print va11,
print va12
def test_c(n1,n2):
print n1,
print n2
n = n1 + n2
return n
print 'Entry programme'
test_a()
test_b(12,13)
test_b('www.baidu.com','python')
sum = test_c(100,102)
print 'sum = ', sum
print 'Leave programme'
Entry programme
hello the cruel world!
www.baidu.com
12 13
www.baidu.com python
100 102
sum = 202
Leave programme
#!/usr/bin/python
def test_a():
print 'hello the cruel world!'
print 'www.baidu.com'
def test_b(va11,va12):
print va11,
print va12
def test_c(n1,n2):
print n1,
print n2
n = n1+n2
return n
def test_d(n1,n2):
print n1,
print n2
n = n1 + n2
m = n1 * n2
p = n1 - n2
e = n1 ** n2
return n, m, p, e
print 'Entry programme'
test_a()
test_b(12,13)
test_b('www.baidu.com','python')
sum1 = test_c(100,102)
print 'sum1 = ', sum1
sum1, multi, plus, pow1 =test_d(2, 10)
print sum1, multi,plus,pow1
print 'Leave programme'
[root@ceshi ~]# python 1.py
Entry programme
hello the cruel world!
www.baidu.com
12 13
www.baidu.com python
100 102
sum1 = 202
2 10
12 20 -8 1024
Leave programme