Sparkstreaming \ updatestatebykey state calculation

Catalog 1, Theoretical basis 2, Code test wordCount 1, code 2. Test data 3. Results display 1, Theoretical basis 1. In flow computing, there is usually a need for state computing, that is, the current computing results not only depend on the current received data, but also need to merge the p ...

Posted on Sun, 16 Feb 2020 01:04:55 -0500 by godwisam

Python basic tutorial: a simple example of using map function to complete Python parallel tasks

This article mainly introduces a simple example of using map function to complete Python parallel tasks. Multithreading and multiprocess programming are always hot and difficult issues in Python. Please refer to As we all know, Python's parallel processing ability is not ideal. I think if we don't consi ...

Posted on Sat, 15 Feb 2020 09:36:11 -0500 by Rovas

Cassandra appender - distributed logging, distributed software logback appender

At the last Scala meetup of the lunar year, Liu Ying was inspired to share her professional software development experience. I suddenly realized that I haven't completely followed any standard development specifications. It is true that there will be no strict requirements for standardized operation in the process of technical research and lear ...

Posted on Wed, 12 Feb 2020 08:46:18 -0500 by eyedol

Calculate the difference between two Java date instances

I use Java's java.util.Date class in Scala and want to compare the date object with the current time. I know that I can use getTime() to calculate the increment: (new java.util.Date()).getTime() - oldDate.getTime() But that only gave me long milliseconds. Is there a simpler and better way to get time increments? #1 building Simple ...

Posted on Sun, 02 Feb 2020 08:16:15 -0500 by harchew

Spark getting started Idea remote submission project to spark cluster

1, Dependent package configuration The related dependency packages of scala and spark. The number of versions underlined after spark package should be consistent with the first two digits of scala version, that is, 2.11 pom.xml <?xml version="1.0" encoding="UTF-8"?> <project xmlns="http: ...

Posted on Thu, 30 Jan 2020 10:39:11 -0500 by max_power

"Class -- basic concept 2" in Scala learning

Catalog Inner class extends override and super override field isInstanceOf and asInstanceOf getClass and classOf Inner class Minnie https://www.amini.net import scala.collection.mutable.ArrayBuffer class Class { class Studen ...

Posted on Wed, 22 Jan 2020 03:49:23 -0500 by Saeven

Architecture Overview of Apache Spark (Chapter 1)

Background introduction Spark is a lightning fast unified analysis engine (Computing Framework) for large-scale data set processing. Spark is doing batch computing of data, and its computing performance is about 10-100 times that of Hadoop MapReduce. Because spark uses advanced DAG based task scheduli ...

Posted on Sun, 19 Jan 2020 02:17:34 -0500 by varsha

11 of scala programming learning - set operation

11.1 mapping map operation of set elements 11.1.1 look at a real demand Requirement: Please * 2 all elements in List(3,5,7), and return the result in a new collection, that is, return a new List(6,10,14). Please write a program to implement it 11.1.2 using traditional methods to solve //Traditional wri ...

Posted on Tue, 14 Jan 2020 03:33:57 -0500 by ashok_bam

Official document of scala mllib -- spark.mllib package -- Classification and expression

3, Classification and expression Spark.mllib package provides a variety of support tools for binary, multiclassification and regression analysis linear models 1) Mathematical formula Many standard machine learning methods can be expressed as convex optimization problems. For example, the task of fin ...

Posted on Sun, 12 Jan 2020 22:19:23 -0500 by aa720

Centos7 compile and install Kafka-manager-2.0.0.2

1, About Kafka manager The project address is: https://github.com/yahoo/kafka-manager In order to simplify the maintenance of Kafka cluster by developers and service engineers, yahoo has built a Web-based tool called Kafka Manager, which is called Kafka Manager. This management tool can easily find out which topics are unevenly distributed in t ...

Posted on Wed, 25 Dec 2019 04:56:22 -0500 by trevorturtle