Programmer Group

1, Decision tree Decision Tree (Decision Tree) is a decision analysis method that calculates the probability that the expected value of net present value is greater than or equal to zero by forming a Decision Tree on the basis of knowing the occurrence probability of various situations, evaluates the project risk and judges its feasibility ...

preface This article introduces the three characteristics of object-oriented. Tip: the following is the main content of this article. The following cases can be used for reference 1, Encapsulation 1. Concept It is one of the three characteristics of object-oriented (encapsulation, inheritance and polymorphism). It is the simulation ...

catalogue 1, State retention 1. HTTP protocol 2. cookie status hold Set cookie return   Save Cookies Not saved   Saved 3. session state hold You need to set the secret key before storing the session 4. Exception handling Custom 500 Custom 404 5. Hook function Before being accessed for the first time, the hook function H ...

1, Construction of decision tree decision tree is a kind of common machine learning algorithm. It makes decisions based on tree structure. Step by step from the root node to the leaf node (decision). All data will eventually fall to leaf nodes, which can be classified or regressed. Decision tree Advantages: the calculation complexity ...

1, JDBC introduction JDBC(Java Database Connectivity) is a common interface (a set of API s) independent of a specific database management system and general SQL database access and operation. It defines the standard Java class libraries used to access the database (java.sql,javax.sql). These class libraries can be used to access database ...

Asynchronous programming catalogue 1, EventLoop 1.JavaScript is a single threaded language 2. Synchronous and asynchronous tasks 3.EventLoop execution process 2, Promise 3, async and await 4, Macro and micro tasks 1, EventLoop 1.JavaScript is a single threaded language Basic concepts JavaScript is a single threaded programming ...

Introduction: excerpt from Yu que document of Lei Fengyang, a teacher from Shangsi Valley Cloud platform Learn to use pay as you go cloud servers for cost-effective development and testing Private network VPC Network related concepts, how to open a cluster on ECS An ECS has two IPS: public IP and private IP Public IP: the access to ex ...

Source: blog.csdn.net/wangwenpeng0529/article/details/105769978 brief introduction Java. Util. Concurrent (JUC) package is provided in Java 5.0. In this package, tool classes commonly used in concurrent programming are added to define custom subsystems similar to threads, including thread pool, asynchronous IO and lightweight task framework; ...

preface In the last article ndnSIM learning (8) -- ndn-simple.cpp of examples analyzes each function line by line In, we analyze the underlying principle of the whole ndn-simple.cpp. As the core, it is naturally the working process of the whole network: how do consumers send interest packets? How do producers return packets based on intere ...

C language and python are often confused, especially I can't help adding a semicolon after Python... Just make a note for myself to save forgetting... (learned on muke.com) 13, Functions 1. Introduction Using functions to encapsulate repeated logic codes, we abstract the process of encapsulating repeated logic codes. Abstraction is a ver ...