Python

What are the common relational databases and non-relational types?MySQL common database engine and comparison?Describe the three main paradigms of data?What is a transaction? How does MySQL support transactions?Describe a one-to-many and

Detail with diagramThe first IO modelBlockingThe second IO modelNon-blocking IOprinciple: change from blocking to non-blocking, come back every once in a while (see once, the kernel will send a system call), if nothing else (for small amount of code)

The Configparser module is used to generate and modify common configuration documents, and the name of the current module is changed to Configparser in the Python 3.x version. Look at a lot of software common document format as follows

String, shaping, floating-point, tuple elements (characters) of the index is immutable, cannot change is that you can use the variable name with square brackets, and then filled in square brackets inside the index value of the string, the index

For Loop One, 1-100 odd Method one: General value for I in Range (1,101): If I% 2==1: Print (i) Method Two: Using step size for I in Range (1,101,2): Print (i) Two, 1-100 odd, 50-70 not printed for I in Range (1,101): If 50 Continue

Example: Xiao Ming has 5 new books, to lend A, B, C three children, if each person can only borrow a copy, how many kinds of borrowing programs? 1 #!/usr/bin/env python2 #-*-Coding; Utf-8-*-3C=04 forAinchRange (1, 5+1):5 forBinchRange (1, 5+1):

#encoding: Utf-8Import Math#向上取整Print "Math.ceil---"Print "Math.ceil (2.3) =", Math.ceil (2.3)Print "Math.ceil (2.6) =", Math.ceil (2.6)#向下取整Print "\nmath.floor---"Print "Math.floor (2.3) =", Math.floor (2.3)Print "Math.floor (2.6) =", Math.floor (2.

Import NumPy as Npdef main (): lst=[[1,3,5],[2,4,6] Print (' Hello World ') print (type (LST)) Np_lst = Np.array (ls T) print (type (np_lst)) Np_lst = Np.array (lst,dtype=np.float) print (Type (NP_LST)) print (Np_lst.shape) print ( Np_lst.ndim)

UnitTest unit tests Compare test results with expected values(1) Inheritance(2) Reference package(3) Execute once test will call setup and teardown(4) Class name starts with test(5) Assertion exception(6) There is a point indicating passing a test

Module In Python, a. py file is called a module. The use of modules can improve the maintainability of external codes.Python built-in functions:To avoid module name collisions, Python introduces a way to organize modules by directory, called

# () groupingImport reprint(Re.search (? p[a-z]+) (? p\d+)','asd123fgh456jkl789'). Group (' name '))Re.search () #懒惰模式 return only the first matching data, and then call the group () method to get a matching stringRe.findall () #贪婪模式, but all

1.Join(concatenation of the string according to the specified stitching character)1 s = input (" Please enter string:")2'_'. Join (s)3print(S1)The meaning of this code is to underline the input string.#利用下划线将列表中的每一个元素连接成字符串 #L =

The SCL source is currently maintained by the CentOS SIG, with additional packages of its own, in addition to recompiling the software collections that builds Red Hat.The source contains a higher version of the program, which can be installed

It's painful to use a Python shell without Tab completion, and here's a record of how to complete it:1. Prepare a tab.py script first.>>> tap.py1 #!/usr/bin/python2 #python tab file3 4 ImportSYS5 ImportReadLine6 ImportRlcompleter7 Importatexit8

1.ORM FrameworkFrom the angle of Use User1 = User (...) User.save () These angles to understand the ORM frameworkBecause the ORM framework itself is a tool for users to use, ORM Framework design needs to design an ORM framework from the perspective

1 #!/usr/bin/env/python32 #-*-codinf:utf-8-*-3 #year:20184 #day:1385 #- xx/xx6 #year:20007 #day:638 #- 03/039 #year:2014Ten #day:63 One #- 03/04 A defis_leap_year (year): - ifYear% 100! =0: - ifYear% 4 = =0: the return1 -

Sort the words in alphabetical order#Change this value for a different result#思路: Using Sort+heyMy_str ="Hello This is a Example with cased letters"" "This is a very troublesome and difficult solution A = My_str.upper () print (a) b = A.split (")

520 This day is also the Internet Valentine's Day. On that day, if there is no girlfriend's own, how to pretend that they have friends! How to "show Love" in a circle of friendsAlthough 520 has passed, but the small series gathered here a lot of

function Definition method in 1.pythondef test (x): "This Istest" y = x*2+1 Return yVaule = Test (2)Print (Vaule)Operation Result:5def: defining function KeywordsTest: Name of function(): Internal definable parameters"": Document

　　Blog Address: http://www.cnblogs.com/yudanqu/First, read the documentHow many steps will it take to install an elephant in a refrigerator? This is also a simple process for reading and writing files, opening files, reading files, and closing files.