Getting started with dplyr

To start off with, I will create an R script called dplyr_intro.R and set up my R environment. First, you should set your working directory to the ch7 project folder. Next, you should read the fuel economyhttps://catalog.data.gov/dataset/consumer-price-index-average-price-data dataset into a dataframe as follows:

setwd("path/to/your/project/folder")
vehicles<-read.csv("data/vehicles.csv")

The next step is to import the dplyr and tibble packages. In R, you can import a package using the library() function. The following lines import the dplyr package and the tibblepackage:

library('dplyr')
library('tibble')

I will start with the select() function. The select() function allows you to select a certain number of columns from a dataframe and returns another dataframe containing only those selected columns. As its first argument, the select() function takes a dataframe. The following arguments to the select() function after the first argument are the names of the columns...