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Lai Yonghao (http://laiyonghao.com) Note: I previously published a concise Python programming specification (see: http://blog.csdn.net/lanphaday/article/details/2834883), which was developed for my company at that time. When I published my blog, alignment and other problems all have some errors and some typos. Later, I made another correction. Around the 8 years in 2010, I switched from C ++ development t

Chapter 1 Welcome to python. Interactive interpreter. Compile-type programming language: Compile the program source code into the target code (machine language ). Compile the program to translate the original program into the target program and save it in another file. Interpreted language: In the implementation of interpreted language, the translator does not generate the target machine code, but produ

In the previous article, we talked about the basic definition and usage of classes, which only embodies one of the three characteristics of object-oriented programming: encapsulation. Let's look at two other features: inheritance and polymorphism. In Python, you can have a class inherit a class, which is called a parent class or superclass, or it can be called a base class, and the inherited class is called

This article transferred from the blog Garden Haizi's article http://www.cnblogs.com/dolphin0520/archive/2013/03/29/2986924.htmlAgain issued thanks to the sharing of Haizi, I read many times, benefited!The basic definition and use of classes are described in the previous article, which only embodies one of the three main features of object-oriented programming: encapsulation.Here's a look at two other features: inheritance and polymorphism.In

** * * * WEEK-01 * * * * * Lecture1 Introduction to Computation: Algorithm is recipes. An algorithm is a conceptual(concept) idea , a program is a concrete instantiation(instantiated) of an algorithm. The embryonic form of modern computers: Stored program computer Basic Primitives: # operating system terminology category. A process consisting of several directives that are used to accomplish a certain function. 5.

[:, Alpha_k] + svm.b) Error_k = Output_k-float (Svm.train_y[alpha_k]) return Error_k # Update The error cache for Alpha K after optimize Alpha K def updateerror (SVM, alpha_k): Error = Calcerror (SVM, Alpha_k) Svm.errorcache[alpha_k] = [1, ERROR] # Select Alpha J which has the biggest step def selectalpha_j (SVM, alpha_i, err Or_i): svm.errorcache[alpha_i] = [1, Error_i] # mark as valid (has been optimized) Candidatealphalist = nonzero (s Vm.erro

difference is that the list can be changed, and tuples cannot be changed.4-9 Exercise, given the following assignment:A = tenB = TenC =d =e = 10.0f = 10.0what is the output of the following expressions?Why? In Python, integer and string objects are non-mutable objects, and Python caches them very efficiently, causing us to think that Python should create new obj

As a result of the previous use of Emacs+jedi for Python programming environment, recently tried the emacs+elpy way. Let's go straight to the next step, less nonsense. First, the system to install the PIP and other tools to facilitate the installation of some Python toolkit (on the CentOS6.5 64-bit system operation),wget Https://bootstrap.pypa.io/ez_setup.py-O-|

Have you thought about what the design pattern is? With this article you can see why design patterns are so important, using several examples of Python to show why design patterns are needed and how to use them.What is the design pattern? Design patterns are summarized, optimized, and reusable solutions to a number of programming problems that we often encounter. A design pattern is not as direct to our c

This article mainly introduces the strings in Python programming, including the formatting of strings and the use of three quotation marks. For more information, see Python escape characters When special characters are needed, python uses a backslash (\) to escape the characters. See the following table: