Kerollmops

Core Coding Standard

Coding practices are a source of a lot of arguments among programmers. Coding standards, to some degree, help us to put certain questions to bed and resolve stylistic debates. No coding standard makes everyone happy. (And even their existence is sure to make some unhappy.) What follows are the standards we put together on the Core team, which have become the general coding standard for all programming teams on new code development. We’ve tried to balance the need for creating a common, recognizable and readable code base with not unduly burdening the programmer with minor code formatting concerns.

Table Of Contents

• Why we need Coding Standards
• Context is Important
• Stylistic Standards

• Namespaces

pratos

Install Zeppelin in Ubuntu systems

• First install Java, Scala and Spark in Ubuntu

  • Install Java

    sudo apt-add-repository ppa:webupd8team/java
    sudo apt-get update
    sudo apt-get install oracle-java8-installer
    

umbertogriffo

  def transposeRowMatrix(m: RowMatrix): RowMatrix = {
    val transposedRowsRDD = m.rows.zipWithIndex.map{case (row, rowIndex) => rowToTransposedTriplet(row, rowIndex)}
      .flatMap(x => x) // now we have triplets (newRowIndex, (newColIndex, value))
      .groupByKey
      .sortByKey().map(_._2) // sort rows and remove row indexes
      .map(buildRow) // restore order of elements in each row and remove column indexes
    new RowMatrix(transposedRowsRDD)
  }

  def rowToTransposedTriplet(row: Vector, rowIndex: Long): Array[(Long, (Long, Double))] = {

Frozenfire92

## Java
sudo apt-get update
sudo apt-get install default-jdk

## Scala
sudo apt-get remove scala-library scala
sudo wget http://scala-lang.org/files/archive/scala-2.12.1.deb
sudo dpkg -i scala-2.12.1.deb
sudo apt-get update
sudo apt-get install scala

vasanthk

System Design Cheatsheet

Picking the right architecture = Picking the right battles + Managing trade-offs

Basic Steps

1. Clarify and agree on the scope of the system

• User cases (description of sequences of events that, taken together, lead to a system doing something useful)
  • Who is going to use it?
  • How are they going to use it?

tsiege

ANNOUNCEMENT

I have moved this over to the Tech Interview Cheat Sheet Repo and has been expanded and even has code challenges you can run and practice against!






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