Python

Thought: All things are objectsHomeworkFirst question:Import NumPy as Npimport matplotlib.pyplot as Pltx = [1, 2, 3, 1]y = [1, 3, 0, 1]def plot_picture (x, y): plt.plot (x, y , color= ' R ', linewidth= ' 2 ', linestyle= '--', marker= ' D ', label=

One, syntax-induced exceptions, should be processed before the program run example: print (Output:file  "e:/python/oldboyday9/learn1.py", line 4     if     ^syntaxerror: invalid syntax Note: The output is divided into three parts, the first part

Pip is used to conveniently manage Python's third-party package, since playing Python is just a scratch, using Python (x, y), but this does not mean that you want to use what package can be found from the inside, so I put Python (x, y) unloaded,

Example: Large file MD5 checksumdefMD5 (FILEMD5):Importhashlib Md5_value=hashlib.md5 () with open (FILEMD5,'RB') as F: whileTrue:　　　　　　　#每次读取2048个字节数据Data= F.read (2048) if notData:Brea #计算md5值md5_value.update

1. File operation.(1) file creation.(2) file read.(3) File rename.(4) File deletion.2. Directory operations.(1) Directory creation.(2) directory deletion.he.py#Coding=utf8ImportOS#Create a filedefWriteFile (FILENAME,STR): FS=open (FileName,"w+")

1. Three-dimensional expression in Python Analogous to the three-mesh operators in C, C + + and Java, Python uses the following statement to implement ternary expressions true_part if condition else false_part。 Condition = True to execute

One: Inter-process data exchange methodThe memory between the different processes is not shared, in order to realize the data exchange between two processes, the following methods can be used:1) queue, using the same method as the threading queue　　#-

Selenium is a Web test application framework that can also be used as a crawler.1. Installing the Selenium modulePip Install-u Selenium2. After installing the Selenium module, the corresponding browser driver is required.A. Using PHANTOMJSPHANTOMJS

There have been a certain Python learning, learning path is mainly based on the Chinese university Mooc Beijing Polytechnic University's Python series.Now proceed to WINDOWS10 64-bit + Python3.6, installed in the directory where the library files

#异常处理#try .... Except, join try exception, execute xcept partTryPrint IExcept Nameerror: #要指明异常类型I=9i+=10print ' I has just not been defined, and the value of I after exception handling is: ' +str (i)#多异常处理TryPrint I+jExcept Nameerror:I=j=0print '

The full name of PIL is the Python image library. But it's not good to use. Strictly speaking, I have not been successful. Because there is always the same error (not a big difference). Even a JPEG image can not be displayed, this library for small

List parsing, primarily for dynamically creating listsThis article focuses on the use of the combination of lambda, map (), and filter () with the list parsing statementsThe basic syntax for list parsing is: [Expr for Iter_var in iterable]At the

The first day to learn python, here to do an exercise!Writing the Login interfaceRequirements: Enter user and passwordShow welcome message after successful authenticationThree-time error after lockingBody Start:#Author:P Eter JoyImport GetpassCount=0

#文件的操作#创建文件Fc=open ("e:/new Folder/a.mp8", "W") #参数1表示文件路径以及名称, Parameter 2 indicates how the file is manipulatedFc=file ("e:/new Folder/a.mp9", "W")#打开文件Fo=open ("e:/new Folder/a.mp9", "W") #若没有此文件open表示创建并打开Fo=file ("e:/new Folder/a.mp9",

1. Strings StringInfer whether a character (char) is a number or a letter#推断是否为字母#推断是否为数字Infer whether a string is emptyifnot#推断是否为空，true表示空Adding content to a string‘‘.join(‘love‘)Get string fixed-length strings>>>str =

For I in range (1,5):For j in Range (1,5):for k in range (1,5):if (i!=j) and (J!=k) and (i!=k):Print I,j,k#任意三个数可组成多少不重复的三位数St=[]For I in Range (1,4):Sa=int (Raw_input (' Your Number: '))St.append (SA)For L in St:For M in St:For N in St:if (l!=m)

function parameters in Python are: default parameter, keyword argument, non-keyword variable-length parameter (tuple), keyword variable-length parameter (dictionary) : Specifies the default value of the formal parameter when the function is

Friend full head Words don't say much, directly on the code Import Itchatimport Mathimport PIL. Image as Imageimport ositchat.auto_login () friends = Itchat.get_friends (update=true) [0:]user = friends[0]["UserName"] num = 0for i in Friends: img

Python adds, deletes, queries, and pythonmysql operations on Mysql Databases Import MySQLdb # introduce the mysql ModuleClass ManagerDB: # create a classDef _ init _ (self ):Self. db = NoneSelf. cursor = NoneSelf. connit ()Def connit (self): # link

Python list parsing and python Parsing List parsing, mainly used to dynamically create a list This article mainly describes the usage of combining lambda, map (), and filter () with list parsing statements. The basic syntax for list Parsing is: