Useful Resources for R

A reference card for R

https://cran.r-project.org/doc/contrib/Short-refcard.pdf

A course on introduction to the R programming language

https://www.datacamp.com/courses/free-introduction-to-r

A resource for different types of plots

https://www.statmethods.net/graphs/line.html

Dataframes

https://chartio.com/resources/tutorials/how-to-sort-a-data-frame-by-multiple-columns-in-r/

http://www.cookbook-r.com/Manipulating_data/Adding_and_removing_columns_from_a_data_frame/

http://rprogramming.net/r-data-manipulation/

Miscellaneous

https://www.computerworld.com/article/2486425/business-intelligence/business-intelligence-4-data-wrangling-tasks-in-r-for-advanced-beginners.html