Python Route 03

First, the module initial

Import Sys

Print (Sys.path) #打印python的环境

Print (SYS.ARGV) #打印相对路径

Print (sys.argv "2") #打印对应的变量

Import OS

cmd = Os.system ("dir")

Print (CMD)

Os.mkdir (' New_dir ')

#第三方库

In the same directory or under Lib/site-package can be directly import, other cases need to write the path

Import

Data operations:

3/2 ==1

5%2 ==1 return remainder

！ =

<>

8bit =byte

1024byte=1kbyte

1024kbyte=1mbyte

1024mb=1gb

2014gb=1t

& | ^ (XOR) ~ (invert) >> right shift << left shift

STR and binary conversions

Operation of the list

names = [' Zhangyang ', ' Guyun ', ' Xiangpeng ', ' Xuliangchen ']

Print (names)
Print (names[0],names[2])
Print (Names[0:2]) #切片, Gu Tou regardless of the tail
Print (names[0:])
Print (Names[-1])
Print (names[-3:])

Names.append ("Leihaidong")
Names.insert (1, ' Chenronghua ')
Names.insert (3, ' Xinzhiyun ')
names[2]= ' Xiedi ' #names. Pop (2)
Names.remove (' Chenronghua ')
Del Names[1]
Names.pop () #删除最后一个

Print (Names.index (' Xiedi '))

Print (Names[names.index (' Xiedi ')])

Print (Names.count (' Xiedi '))
Names.clear ()
Names.reverse () #反转
Names.sort () #排序

names1=[1,2,3,4]
Names.extend (NAMES1)

Names2 = Names.copy () #浅copy
names[1]= ' SD '
Print (Names,names2) #names变了, names2 unchanged

#但是names还有一层的话, all changed.

Import Copy
Names3 = copy.copy (names)
Names3 = copy.deepcopy (names)

For I in Range (1,10,2):
    Print (i)

Python Route 03