Multiple ways to subsetting data frames in R

Subsetting a data frame is an essential and frequently performed task. Here, some basic ideas are presented. Get some data first. str(mtcars) ## ‘data.frame’: 32 obs. of 11 variables: ## $ mpg : num 21 21 22.8 21.4 18.7 18.1 14.3 24.4 22.8 19.2 … ## $ cyl : num 6 6 4 6 8 6 8 4 4 6 … ## $ disp: num 160 160 108 258 360 …