• Talk about the eventtime of Flink


    order This paper mainly studies the eventtime of Flink SourceFunction flink-streaming-java_2.11-1.7.0-sources.jar!/org/apache/flink/streaming/api/functions/source/SourceFunction.java /** * Interface that source functions use to emit elements, and possibly watermarks. * * @param <T> The type of the elements produced by the source. */ @Public // Interface might be extended in the future with additional methods. interface SourceContext<T> { /** * […]

  • Statistical learning 3: linear support vector machine (SVM)


    learning strategy Soft interval maximization The “linearly separable support vector machine” defined in the previous chapter requires that the training data be linearly separable. However, in practice, the training data often include outliers, so it is often linear and inseparable. This requires us to make some modifications to the algorithm in the previous chapter, that […]

  • PHP + redis solves practical problem 1: order flow restriction


    1. Each issue of this series of articles will solve a practical redis problem2. Questions in each issue will be selected from the comments in each issue3. Questions are limited to those related to redis. If I am interested in other questions, I will not rule out opening up a new series4. I often use […]

  • Why use setTimeout to simulate setinterval?


    stayMacro task and micro task of JS event loopAs mentioned in, setinterval is a macro task. If you use more, you will find that it is not accurate, and some puzzling problems will appear in extreme cases. Let’s list them one by one The time after pushing the task queue is not accurate Timer code: […]

  • JS timer mechanism and front-end animation from n implementations of typewriter effect


    First, what is the typewriter effect? Typewriter effect is to output text one by one, which is actually a kind of Web animation. A picture is worth a thousand words. Please see: In web applications, there are many ways to realize animation effects. In JavaScript, it can be realized by timer setTimeout, CSS3 can be […]

  • 99% of people can understand the “compensation” mechanism of distributed systems


    Summary:Let’s talk about how to digest the “internal injury” through the “compensation” mechanism while ensuring high external availability. 1、 What is the significance of the “compensation” mechanism? Take the shopping scenario of e-commerce as an example: Client – > shopping cart micro Service – > order micro Service – > payment micro service. This call […]

  • The golang implementation calculates prime numbers in the range of 1 to 100000


    1. Calculate the prime number in the range of 1 to 100000, and implement golang package concurrentdemo import ( “fmt” “sync” ) //1-10000000 Var start int = 0 // start value //Var end int = 1000000 // end value var end int = 1000 Var interval int = 100 // divide goroutine interval var wg […]

  • Machine learning algorithm (5): classification and prediction based on support vector machine


    Statement: the learning materials provided by the datawhale team are mainly self-study, the code is provided by the datawhale team, and the test is completed by using Alibaba cloud Tianchi laboratory and editor pycharm.Support vector machine (SVM) is a very elegant algorithm with very perfect mathematical theory. It is often used in data classification and […]

  • How to solve 503 error code?


    POM file dependency <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter</artifactId> </dependency> <!–gateway fhadmin.org–> <dependency> <groupId>org.springframework.cloud</groupId> <artifactId>spring-cloud-starter-gateway</artifactId> <version>3.0.2</version> </dependency> <!–spring-boot fhadmin.org–> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies> clickMobile GamesLabel and drag to moveThe related dependencies of Nacos I added in the parent component are as follows: <dependency> <groupId>com.alibaba.cloud</groupId> <artifactId>spring-cloud-starter-alibaba-nacos-config</artifactId> <version>${nacos.version}</version> </dependency><!–alibaba fhadmin.org–><dependency> <groupId>com.alibaba.cloud</groupId> <artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId> <version>${nacos.version}</version> </dependency> Click and drag […]

  • Some small problems and solutions in realizing simple sports with timer in JS BOM


    Simple movement Simple movement: it is a visual persistence effect. As long as the time of element change process is short enough, the effect on human eyes is a movement effect. The visual residual time of human eyes is 0.1 ~ 0.4 s Through the timer, the function can be executed every very short time […]

  • How to expand the horizontal capacity of the distributed monitoring system wgcloud and server


    First, starting from V3.0, wgcloud supports the server cluster mode, master slave. Download: http://www.wgstart.com Less than 500 monitoring hosts do not need to be used for server clustering and load balancing. The server is a spring boot architecture and naturally supports high concurrency. Note the configuration of the server, config / application.yml #Custom configuration parameters […]

  • [Android] control scheme for continuously clicking the control for multiple times (new monitoring class)


    reference resources:Three ways to prevent Android from clicking too fast and causing multiple events_ Fat blog – CSDN blog The implementation logic is simple: Set time limit Start timing when the user clicks If the timing does not exceed the limit time, the click event is not allowed to be triggered Because you haven’t learned […]