Files can be listed by using “list.files()”, which will return possible files. The source command will run a script, and is shown below.
> source("bottle1.R")
[1] "This be a message in a bottle1.R!"
R can read a .csv file, which literally means comma separated values.
The example below shows a csv, titled targets.csv, being read.
read.csv("schools.csv")
University Students Tuition
1 Truman State University 6200 13500
2 University of Iowa 33300 29000
3 University of Michigan 44700 45000
4 University of North Texas 37900 20000
Text files (.txt) can also be read, but if the separator is a tab, the
“read.table” command is a better fit. The following example shows the tab
separator specification (sep="\t").
read.table("population.txt", sep="\t")
V1 V2
1 City Population
2 Joliet 148262
3 Kirksville 17519
4 Denton 133808
5 New Lenox 26217
This example had V1 and V2 as headers. R isn’t automatically aware that they are headers, so that needs to be specified when reading the table.
read.table("population.txt", sep="\t", header=TRUE)
City Population
1 Joliet 148262
2 Kirksville 17519
3 Denton 133808
4 New Lenox 26217