Python

Python supports four blending of integers and floating-point numbers directly, and the arithmetic rules are exactly the same as the arithmetic rules in mathematics.Basic operations:1 + 2 + 3 # ==> * 5-6 # ==> 147.5/8 + 2.1 # ==> 3.0375Using

1. The core of each if statement is an expression with a value of true or false, which is called a conditional test2. An equal sign is a statement, two equals is a question, check if the case is not considered equalCar = ' BMW 'Car = = ' Audi 'FALSE3

Position parametersdef power(x): return x*x; Default parametersWhen a function is defined, it is given the default value of the parameter, and it is not necessary to pass the duplicate parameter value multiple times when calling the

Variable Declaration and assignmentDeclaring variables: name = "Alex Li"The code above declares a variable named: name, and the value of the variable name is: "Lanhan"#! Author:lanhanName = "Lanhan"name2 = NamePrint ("My name is", name)Name =

This chapter will combine the previously learned crawlers and regular expression knowledge to do a simple crawler case, for more information, please refer to: Python Learning Guide Now that we have the regular expression, the weapon of the

Adorner:Definition: The essence is a function, function: (Decorate other functions) is to add additional functions for other functions;Principle: 1, cannot modify the source code of the adornment function2. Cannot modify the calling mode of the

DataLinear tables include sequential tables and linked lists, and Python lists are sequential tables, which are generally not used in dynamic languages. But the list will still appear in a variety of algorithm problems.Linked list: Single

1 >>> a,*rest,b = range (5)2 >>> a,rest,b3 (0, [1, 2, 3], 4)4 >>> a,*rest,b = Range (5) >>> a,rest,b (0, [1, 2, 3], 4) 　　Pythonthe pros and consSee the pros first Python's positioning is "elegant", "clear", "simple", so the Python program

One: Head insert #!/usr/bin/env pythonDeclare the interpreter and tell the operating system what it means to explainTwo: variable \ character encoding1 Development tools: Pycharm2 print ("Hello World")3 name= "Laowu" Name2=namePrint ("My name is",

Serialization modules: JSON and PickleTwo modules for serialization JSON, used to convert between string and Python data types Pickle for conversion between Python-specific types and Python data types The JSON module provides four

In Python, assignment and comparison operations can be connected, and operators can be used together, such as: 0 The = = operator Determines whether two objects are equal, is to determine whether the two are equal (the same object) Assert that

First, ListList changes and additions#Increase,Classmates.append ("Nadech")#append an element at the end of theClassmates.insert (1,"Aguilera")#Insert at a location with an index value of 1#DeleteClassmates.pop ()#remove an element from the

CentOS6.6 's own Pythonversion to 2.6. 6,want to upgrade him, installing Python2.7.9First, Preparing the installation packagewget https://bootstrap.pypa.io/get-pip.py #下载setuptools和pip wget Https://pypi.python.org/packages/source/i/ipython /ipython-

1. String merging and linkingPlus sign MergeJoin method Merge2, multiply and sliceLine= ' * ' *30Print (line)>>******************************Slice:Consequence[start_index:end_index:step]Represents the first element, the positive index position

In fact, Python does the same thing as doing MySQL transactions:[email protected] ~]# cat1. py#!/usr/bin/env pythonimport mysqldbdef connect_mysql (): Db_config= { 'Host':'127.0.0.1', 'Port':3306, 'User':'Root', 'passwd':'

Python string concatenation of 6 ways:1. PlusFirst, people with programming experience know that many languages use a plus sign to connect two strings, and Python also uses "+" directly to connect two strings; 1

Today is 2017-05-03, here are some basic methods of using Python. There is no sorrow in the world that cannot be shed, and this sorrow cannot be explained to others, even if it is explained. It is always static, such as no wind at night snowflakes

In Python, the difference between curly braces, brackets, and parenthesesPython has three main data types: dictionaries, lists, and tuples. It is represented by curly braces, brackets, and parentheses, respectively. such as: Dictionary: dic={' A ':,

Python (https://www.python.org/ftp/python/)First, tool installation1, the installation of Python1 tar vxf Python-2.7.13. tgz2 cd Python-2.7.13. tgz3 ./Configure 4 make && make install2, Installation SetuptoolsDownload

Serialization module# Serialization method# format Conversion# Convert data in Python to str---serialization# Data---Deserialization that can be converted to Python by strJSON module# JSON All languages are universal, and the data it can serialize