Interactive Course

Joining Data with data.table in R

This course will show you how to combine and merge datasets with data.table.

  • 4 hours
  • 13 Videos
  • 47 Exercises
  • 7,020 Participants
  • 3,950 XP

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Course Description

In the real world, data sets typically come split across many tables while most data analysis functions in R are designed to work with single tables of data. In this course, you'll learn how to effectively combine data sets into single tables using data.table. You'll learn how to add columns from one table to another table, how to filter a table based on observations in another table, and how to identify records across multiple tables matching complex criteria. Along the way, you'll learn how to troubleshoot failed join operations and best practices for working with complex data sets. After completing this course you'll be well on your way to be a data.table master!

  1. 1

    Joining Multiple data.tables


    This chapter will show you how to perform simple joins that will enable you to combine information spread across multiple tables.

  2. Joins Using data.table Syntax

    In this chapter you will perform joins using the data.table syntax, set and view data.table keys, and perform anti-joins.

  3. Diagnosing and Fixing Common Join Problems

    This chapter will discuss common problems and errors encountered when performing data.table joins and show you how to troubleshoot and avoid them.

  4. Concatenating and Reshaping data.tables

    In the last chapter of this course you'll learn how to concatenate observations from multiple tables together, how to identify observations present in one table but not another, and how to reshape tables between long and wide formats.

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Scott Ritchie
Scott Ritchie

Postdoctoral Researcher in Systems Genomics

Scott Ritchie is a Post-doctoral Researcher in the field of systems genomics. He applies and develops tools to analyse genetic and molecular data in population studies of common diseases. He is a daily user of R and the data.table package. He has contributed to development of the data.table package and to course material used by Software Carpentry. He holds an MSc in Bioinformatics and a PhD in systems biology.

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