Superscript to subscript

[ssrsrb]

Change superscript 2 in CO^2^ to subscript 2. I think it goes like this: CO_2

(not sure if this the most efficient way of reporting it)
efficientR/ Chapter 5.3 Line 99

There is often more than one way to read data into R and .csv files are no exception. The method you choose has implications for computational efficiency. This section investigates methods for getting plain text files into R, with a focus on three approaches: base R's plain text reading functions such as read.csv(); the data.table approach, which uses the function fread(); and the newer readr package which provides read_csv() and other read_*() functions such as read_tsv(). Although these functions perform differently, they are largely cross-compatible, as illustrated in the below chunk, which loads data on the concentration of CO^2^ in the atmosphere over time:

[csgillespie]

Thanks! I'll try and fix it in the near future