Hi! I am Mike Marin and in this video we'll talk about
how to import data from Excel into R. the steps outlined in this video
should work with most other spreadsheet applications
but since Excel is fairly commonly used we will focus our discussion on this
Our two main options will be to save the data file
as a comma-separated value or ".csv"
file or as a tab-delimited text file
with the ".txt" extension. Saving it as a csv file
is probably easier and the better way to go! let's go ahead and save this file
on the desktop as a csv file: to do so
under the "File menu" we can go to "Save As..."
we're going to save it on our desktop
and we can save this as a "comma-separated" value
or csv file. I'm also gonna add the
CSV to the end of the file name just so it's easily identifiable
we can see
the ExceldataCSV file saved here on the desktop
you'll notice if we double click on this file to open it
by default it will open in Excel
let's go ahead and close this. You'll notice if we right click
on this file we can "Open With..." and open it in any text editor that we like
this here is what the csv file looks like
in a text editor. okay so let's go ahead
and import this data into R. so I've gone ahead and
opened up RStudio and R. the first option for importing data
is to use the "read.csv" command. you can access the Help menu
by typing help and in brackets the name of the command you will like help for
or by placing a question mark (?) in front of the command name;
let's go ahead and import this data into R
and save it in an object called "data1". To do so
we will use the "read.csv" command. the first argument to specify
is the "file". normally R would like us to specify
the path to find the file here but a handy command to know
in R is the "file.choose" command. rather than specifying the path to find this file
we can use the "file.choose" command and this will result in a menu popping up
allowing us to select the data file directly. the next argument that we
should worry about
is the "header" argument. we can set this equal to TRUE
using capital letters to let R know that the first row of our dataset
are variable names or headers. if the first row does not contain variable
names we would set the sequel to FALSE
it's also worth noting that we only need to provide a capital T
and R will know this is TRUE. we can then submit this command
by hitting the "enter" or "return" key on our keyboard. we can now go and find this
file that we saved on the desktop : our "ExceldataCSV.CSV"
select this file and now
if we type in the object's name "data1" we can see the entire dataset return to us.
it looks like R has imported this dataset correctly
we can also see in the workspace this object data1
which has 10 observations on 6 variables
we can also import this data using the more generic
"read.table" command. lets demonstrate the use of this command
and import the data into R and save it in an object called "data2"
here we will use the "read.table" command
again we will use the "file.choose" command
we will set the "header" argument equal to TRUE
and here we also need to use the "sep" argument
letting R know how the data values are separated
in quotations we will place a comma letting R know these are comma separated values
we can then submit this command, go on our desktop
select the "ExceldataCSV.CSV" file
and when we type in the name of this object
again we can see the data has been imported correctly.
now let's go back to our excel file
and look at importing data saved as a tab-delimited text file
once again you can see our Excel data file
we can go ahead and save this file as a tab-delimited text file
here I will select the tab-delimited file with a .txt
extension and we will also
add the word TAB to the end of this file name, so we can be easily identify this is the
tab-delimited file. we can then save it
and now we can see this tab-delimited text file saved on the desktop here
you'll notice if you double-click on this file to open it
by default it will be opened in a text editor
you can also notice these values are separated by tabs
let's go ahead and close this down. to open this file
using Excel we can right click
"open with" and select Microsoft Excel
and now we'll see our tab-delimited text file opened up in Excel
now let's go back into RSstudio and import this data file
we can use the "read.delim" command in R
to import a tab-delimited text file
let's go ahead and import this dataset using the "read.delim" command
and we will save the data into an object called data3
we will use the "read.delim" command
as before we use the "file.choose" command so that we can select our file from menu
we can set the "header" argument equal to TRUE once we enter this command:
we can go onto the desktop open up our tab-delimited
text file. again if we enter the object name
we can see the data has been imported correctly
and finally as we saw before we could also use the more generic
"read.table" command. let's demonstrate this and save the
data in an object called data4
we'll use the "read.table" command. again
"file.choose" so that we can select our file
"header" equal to TRUE and finally we can set
the "sep" argument equal to back-slash t (\t)
letting R know this is a tab-delimited file
we can go ahead and select the file
we can enter the dataset's name to view it
and again the data looks as it should. the next video in the series
talks a bit more about importing data and then how to get started working with
the data in R
once you've imported it. thanks for watching this video
and make sure to check out my other instructional videos