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Joining Data with data.table in R

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

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4 Hours13 Videos47 Exercises12,464 Learners3950 XPData Analyst TrackData Manipulation Track

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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.

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    Welcome to the course
    50 xp
    Exploring data.tables
    100 xp
    Identifying join keys
    50 xp
    Multiple data.tables, multiple keys
    50 xp
    The merge function
    50 xp
    Inner join
    100 xp
    Full join
    100 xp
    Left and right joins
    50 xp
    Left join
    100 xp
    Right join
    100 xp
    Mastering simple joins
    100 xp
  2. 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.

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In the following tracks

Data Analyst Data Manipulation


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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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