Programmer Group

1. Local mode The so-called Local mode is an environment in which Spark code can be executed locally without any additional node resourcesCommonly used for teaching, debugging, presentations, etc. The environment in which code was previously run in IDEA is called a development environment, which is different. 1.1 Installation Configurati ...

Java generics (1): generic classes, generic interfaces, and generic methods Java generics (2): unbounded wildcards, upper wildcards, and lower wildcards Java Generics (3): Type Erase Preface Generalization is a very important feature in our development, especially in scenarios involving collections, polymorphisms or custom classes. But ...

Purpose: (1) Understand the role of HBase in Hadoop architecture. (2) Proficient in using HBase to operate common Shell commands. Objectives: (1) Be familiar with hbase related operations, and master the operations of creating tables, modifying tables, looking up tables, deleting tables, etc. (2) You can create a table by yourself, be familiar ...

1, Deep and shallow copy Shallow copy: When implementing a string, if you do not copy the string first, a copy constructor will be automatically generated, but it is only a shallow copy. Two string objects point to the same address. When two objects call the destructor, the destructor called by the previous object has released the internal sla ...

0x0. Preface In the previous section, we transferred the Operation lowing of Toy Dialect to after dialect, MemRef Dialect and Standard Dialect, while the toy.print Operation remains unchanged, so it is also called partial lowing. Through this lowing, the lower level implementation logic of Toy Dialect's Operation can be expressed to seek more ...

Operation requirements: a. The side length of the pyramid is 2; b. The color of each vertex of a pyramid is different; c. The center of the pyramid is (1,2,3); d. It is required to use a variety of lights, including ambient light, specular light and scattered light, which can be reflected by controlling the object Material factors and ...

Introduction to K-means clustering algorithm k-means clustering algorithm is an iterative clustering analysis algorithm. It is also regarded as unsupervised learning, the simplest clustering algorithm. The overall idea is to divide the data into K groups, randomly select K objects as the initial cluster center, then calculate the dis ...

Bucket sorting: The sorting under the bucket sorting idea is not based on comparison, and the application range is limited. The data status of the sample needs to meet the bucket division. The following describes the two sorting methods under the bucket sorting idea (1) Count sort (2) cardinality sort Time complexity O(N) Count so ...

Hamiltonian problem and Hamiltonian ring In 1859, the Irish mathematician Hamilton proposed the following game to travel around the world: London, Paris, Moscow and other world-famous cities were marked on the 20 vertices of the regular dodecahedron, and the edges of the regular dodecahedron represent the routes connecting these cities. Can yo ...

Basic use, upload and download of private server Why build a private server The network speed is slow, it takes a long time to download jar packages, and the work efficiency is low It is not conducive to the management and maintenance of public construction The jar packages developed in the company can only be shared and managed by the comp ...