• Exercises in Chapter 10 of statistical learning methods

Time：2021-11-29

Exercise 10.1 By the question,$$T=4, N=3,M=2$$ According to algorithm 10.3 The first step is to calculate the final period$$\beta$$ ： $$\beta_4(1) = 1, \beta_4(2) = 1, \beta_4(3) = 1$$ The second step is to calculate each intermediate period$$\beta$$ ： $$\beta_3(1) = a_{11}b_1(o_4)\beta_4(1) + a_{12}b_2(o_4)\beta_4(2) + a_{13}b_3(o_4)\beta_4(3) = 0.46$$ \(\beta_3(2) = a_{21}b_1(o_4)\beta_4(1) + a_{22}b_2(o_4)\beta_4(2) + a_{23}b_3(o_4)\beta_4(3) […]

• Bit operation skills in react source code

Time：2021-10-13

Hello, I’m Carson. Many friends and I make complaints about it in the past two years.ReactSource code, such as: Why does the scheduler use the data structure of small top heap instead of array? In the source code, all kinds of one-way linked lists and ring linked lists can’t you use arrays directly? Various bit […]

• Golang toolset – string tool, time tool, HTTP tool, etc

Time：2021-9-14

gotool Gotool is a small and complete tool set of golang, which mainly refines and integrates the methods commonly used in daily development, avoids repeated wheel making and improves work efficiency. Each method is extracted from the author’s work experience and previous projects. Please refer to the document for details of the updated content on […]

• Understanding generator

Time：2021-8-27

1. Set while in the generator to true The Redux saga document mentions that take implements takeevery and uses yield in while to monitor future actions Infinite cycles function* watchRequests() { console.info(“xx”); let preVal = 0; while (true) { console.info(“yy”); const ret = yield preVal + 2; // if (ret === 3) { // break; […]

• The journey of leetcode [simple part] – 7. Integer inversion

Time：2021-5-1

subject Given a 32-bit signed integer, you need to invert the number on each bit of the integer.Given a 32-bit signed integer, reverse digits of an integer.Examples   1: Input:123Output: 321Example 2:Input: -123Output: -321Example 3:Input: 120Output: 21 Personal thinking First of all, it should be noted that Chinese topics will cause misunderstanding. 32-bit signed integer […]

• Flink SQL CDC practice and consistency analysis

Time：2021-4-22

This article, shared by Wang Jian and Wen Qiao of Minsheng Bank, mainly introduces the practice and consistency analysis of Minsheng Bank’s Flink SQL CDC. The contents include: background What is Flink SQL CDC connectors Introduction to the principle of Flink SQL CDC Three data synchronization schemes Verification of Flink SQL CDC + jdbc connector […]

• CompletableFuture

Time：2020-10-3

Overview of completable future Completable future is a future that can be programmed to explicitly set the calculation result and state so that the task can be ended. It can be used as a completion stage. When its calculation is completed, a function or behavior can be triggered. When multiple threads attempt to call the […]

Time：2020-8-15

Flink’s world view is data flow For Flink, the main scenario to be processed is stream data. Batch data is only a limited special case of stream data. Therefore, Flink is also the computing engine of real streaming batch system Unbounded streams？Bounded streams？ Unbounded flow and bounded flow stateful computations？ Stateful calculation: each time data […]

• Experience of promise

Time：2020-1-22

General usage var promise = new Promise(function (resolve, reject) { setTimeout(resolve, 500, ‘P1’); }); perhaps function createPromise(){ return new Promise(function (resolve, reject) { resolve(request.responseText); }); } Chain operation Create first promise var p = new Promise(function (resolve, reject) { log(‘start new Promise…’); resolve(123); }); p.then().then()…. perhaps var p=Promise.resolve(’13’); perhaps var p=Promise.resolve(’13’); p.then().then() Then chain Then […]

• [reprint] two significant decimals are reserved for decimal in C ා

Time：2020-1-6

In the process of C ා number operation, sometimes it is necessary to reserve two significant decimals for decimal type calculation, and there are many ways to reserve two significant decimals for decimal variable. You can use math.round method and toString to convert to string first. (1) Method 1: use the math. Round method in […]