1st Edition

Testing R Code

By Richard Cotton Copyright 2017
    196 Pages
    by Chapman & Hall

    196 Pages 10 B/W Illustrations
    by Chapman & Hall

    196 Pages 10 B/W Illustrations
    by Chapman & Hall

    Learn how to write R code with fewer bugs.

    The problem with programming is that you are always one typo away from writing something silly. Likewise with data analysis, a small mistake in your model can lead to a big mistake in your results. Combining the two disciplines means that it is all too easy for a missed minus sign to generate a false prediction that you don’t spot until it’s too late. Testing is the only way to be sure that your code, and your results, are correct.

    Testing R Code teaches you how to perform development-time testing using the testthat package, allowing you to ensure that your code works as intended. The book also teaches run-time testing using the assertive package; enabling your users to correctly run your code.

    After beginning with an introduction to testing in R, the book explores more advanced cases such as integrating tests into R packages; testing code that accesses databases; testing C++ code with Rcpp; and testing graphics. Each topic is explained with real-world examples, and has accompanying exercises for readers to practise their skills — only a small amount of experience with R is needed to get started!



    Run-time testing with assertive

    Development-time testing with testthat

    Writing easily maintainable and testable code

    Integrating testing into your packages

    Writing your own assertions and expectations

    Answers to exercises


    Richard Cotton