Programmer Group

Catalog 1. Folders (libraries) Add: Change: Check: Delete: 2. Documents (tables) Add: Change: Check: Delete: 3. One line of the document Add: Change: Check: Delete: 4. Complete grammar for creating ...

Custom tokens To create a new custom token (user_issued_asset), use the create_user_issued_asset method. In addition to the symbol and precision parameters, you can change other parameters by calling the update_asset command. Note that if the param ...

MongoDB synchronization principle, the official documents introduced less, online information is not too much, the following is a combination of official documents, online information and testing logs, sorted out a little.Because each fragment of MongoDB is also a replica set, only the synchronization principle of the replica set is needed. I. ...

Map: Independent Interface HashMap: Use hash tables to ensure that keys do not repeat: int hashCode() boolean equals(Object obj) TreeMap: Use binary tree, sort by key, Comparable < E > int compare To (E) Comparator < E > int compare (E 1, E 2) Note: compare To () or comparison method return value of 0 is considered to be t ...

Long ago, people did not want to use processes in order to continue to enjoy the benefits of parallelism, so they created lighter threads than processes. Taking linux as an example, creating a process needs to apply for new memory space and copy some data from the parent process, so the overhead is relatively large. Threads (or lightweight proc ...

Python Basic Data Types for Python Introduction 1. Integer: int For calculation, for comparison (the right side of the equals sign is executed first when assigning values) The addition of 1.1 integers a = 10 b = 20 print(a + b) //Result: 30 Subtraction of 1.2 integers a = 10 b = 20 print(b - a) //Result 10 Multiplication of 1.3 Integers a = 10 ...

Today we continue to talk about the implementation of blocking queue. Today's protagonist is Priority Blocking Queue. From the naming point of view, it should be orderly. After all, it's priority queue. So what's the actual situation? Let's look at its internal implementation together and explain in advance, because Priority Blocking Queue is i ...

1 Introduction For the directional strategy of pure bull or short, only when the stock price is a mean regression or trend, can the trading strategy be profitable. Otherwise, if the price is random walk, the transaction will be unprofitable (Fa ...

What can the inRange function do? Target tracking and color recognition. In the process of inRange application, it is important to find the appropriate HSV value. RGB is the most widely heard color space, which is also the natural representati ...

day08 [String class, static keyword, Array class, Math class] Today's Content String class static keyword Array class Math class target Ability to create string objects using String class constructors Ability to specify the cons ...