Make sure that the data file is saved in your working directory. You
can check to see what your working directory is by starting R, and
typing getwd(). If you wish to use a different directory as
your starting directory, use setwd("dirpath")
, where
"dirpath"
is the full directory path of the directory you would
like to use as your working directory.
After setting your working directory, load data using one of the
following methods:
- If your dataset is in a tab- or space-delimited .txt
file, use read.table("mydata.txt")
- If your dataset is a comma separated table, use
read.csv("mydata.csv").
- To import SPSS, Stata, and other data files, use the
foreign package, which automatically preserves field characteristics
for each variable. Thus, variables classed as dates in Stata are
automatically translated into values in the date class for R. For
example:
> library(foreign) # Load the foreign package.
> stata.data <- read.dta("mydata.dta") # For Stata data.
> spss.data <- read.spss("mydata.sav", to.data.frame = TRUE) # For SPSS.
- To load data in R format, use load("mydata.RData").
- For sample data sets included with R packages such as Zelig, you
may use the data() command, which is a shortcut for loading
data from the sample data directories. Because the locations of
these directories vary by installation, it is extremely difficult to
locate sample data sets and use one of the three preceding methods;
data() searches all of the currently used packages and loads
sample data automatically. For example:
> library(Zelig) # Loads the Zelig library.
> data(turnout) # Loads the turnout data.
Gary King
2011-11-29