Book Image

Scala Machine Learning Projects

Book Image

Scala Machine Learning Projects

Overview of this book

Machine learning has had a huge impact on academia and industry by turning data into actionable information. Scala has seen a steady rise in adoption over the past few years, especially in the fields of data science and analytics. This book is for data scientists, data engineers, and deep learning enthusiasts who have a background in complex numerical computing and want to know more hands-on machine learning application development. If you're well versed in machine learning concepts and want to expand your knowledge by delving into the practical implementation of these concepts using the power of Scala, then this book is what you need! Through 11 end-to-end projects, you will be acquainted with popular machine learning libraries such as Spark ML, H2O, DeepLearning4j, and MXNet. At the end, you will be able to use numerical computing and functional programming to carry out complex numerical tasks to develop, build, and deploy research or commercial projects in a production-ready environment.
Table of Contents (17 chapters)
Title Page
Packt Upsell
Contributors
Preface
Index

Data pre-processing and feature engineering


I already stated that all the 24 VCF files contribute 820 GB of data. Therefore, I decided to use the genetic variant of chromosome Y only one two make the demonstration clearer. The size is around 160 MB, which is not meant to pose huge computational challenges. You can download all the VCF files as well as the panel file from ftp://ftp.1000genomes.ebi.ac.uk/vol1/ftp/release/20130502/.

Let us get started. We start by creating SparkSession, the gateway for the Spark application:

val spark:SparkSession = SparkSession
    .builder()
    .appName("PopStrat")
    .master("local[*]")
    .config("spark.sql.warehouse.dir", "C:/Exp/")
    .getOrCreate()

Then let's show Spark the path of both VCF and the panel file:

val genotypeFile = "<path>/ALL.chrY.phase3_integrated_v2a.20130502.genotypes.vcf"
val panelFile = "<path>/integrated_call_samples_v3.20130502.ALL.panel "

We process the panel file using Spark to access the target population data and...