Data Types

Some of the most common variable classes you will encounter include:

• Character
• Numeric (Double)
• Integer
• Factor
• Date
• POSIXt
• Logical

And common data types include:

• Character
• Numeric (Double)
• Integer
• Logical

Review variable structure

• Review data types

Convert variable class

• Convert variable class to numeric
• Convert variable class to character
• Convert variable class to factor
• Convert variable class to date

Convert variable class using a dictionary

• Convert variable class using a dictionary

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Main functions used in examples

Package	Functions
base	class(); typeof(); as.factor(); as.numeric(); as.character()
utils	str()
lubridate	as_date(); as_datetime(); mdy(); parse_date_time()
forcats	as_factor(); fct_relevel()
janitor	excel_numeric_to_date()
dplyr	glimpse()

Other functions used in examples

Package	Functions
base	attributes(); levels()
dplyr	mutate(); across(); all_of(); pull()
purrr	map()
tidyselect	everything(); where()

Resources

• https://tibble.tidyverse.org/articles/types.html
• https://swcarpentry.github.io/r-novice-inflammation/13-supp-data-structures/
• https://resbaz.github.io/2014-r-materials/lessons/01-intro_r/data-structures.html
• https://mgimond.github.io/ES218/Week02a.html
• https://stackoverflow.com/questions/8855589/a-comprehensive-survey-of-the-types-of-things-in-r-mode-and-class-and-type
• https://evoldyn.gitlab.io/evomics-2018/ref-sheets/R_lubridate.pdf
• https://www.youtube.com/watch?v=_rPde-SPDVE
• https://www.youtube.com/watch?v=OEweA4yVAuI
• https://www.r-bloggers.com/2013/08/date-formats-in-r/
• https://rdrr.io/cran/janitor/man/excel_numeric_to_date.html
• https://epirhandbook.com/en/working-with-dates.html