6  Packages

When it comes to sharing your code with others, you may:

• Share an .R script
• Share an .RData image
• Build and share a package
• Packages we used already: dplyr, tidyr, lubridate, foreign

A package bundles together code, data, documentation, and tests, and is easy to share with others. As of June 2019, there were over 14,000 packages available on the Comprehensive R Archive Network, or CRAN, the public clearing house for R packages. This huge variety of packages is one of the reasons that R is so successful: the chances are that someone has already solved a problem that you’re working on, and you can benefit from their work by downloading their package. - Chapter 1 Introduction, R Packages

sessionInfo()

SO: In R, what does “loaded via a namespace (and not attached)” mean?

• CRAN - R
  • CPAN - Perl
  • PyPI, Conda - Python
  • npm - JavaScript
  • As of Sep. 2021:
    • there are over 18,000 packages indexed on MetaCRAN.
    • ggplot2 is the most downloaded package
    • knir is the most depended upon package
• Many more packages are available on Github

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• Tidyverse is a collection of R packages

  • tibble, tidyverse’s data frame
  • ggplot2, graphics
  • dplyr, data manipulation
  • tidyr, data tidying
  • …
  • similar to pandas for Python

• To see where your packages are saved on the computer: .libPaths()

• To list all packages available on the computers: lapply(.libPaths(), dir)

• With package x:

  • install.packages("x") to install from CRAN
  • library("x") to use the package
  • package?x to get help
    • package?graphics
    • package?ggplot2
  • Use cheat sheets

• To create a package ?devtools::create

• A package has its own environment (see Fundamentals II)

  • ls("package:x") lists all objects in that package
  • e.g. ls("package:graphics")