Software tutorial/Basic plots in R
A simple sequence plot
We will continue on with the data set described in the previous section. Load the dataset and let's plot the column called
Visits - there are 4 columns in the dataset, so we must be specific on which one to plot.
website <- read.csv('http://openmv.net/file/website-traffic.csv') plot(website$Visits)
Which produces this figure. Note that the defaults in R are to leave a lot of white space around the figure. We will show later how to remove that.
That plot shows only the points (markers), in the order of the data set. What if you want lines between the points? Type
help(plot) to find out more about the
plot command. For example, it tells you there that
type="p" will just show the points (the default setting for
If you use
type="l" you get a line plot:
type="b" will show both lines and points, leaving a space between the point and the line connections
type="o" will connect (overplot) the lines and points.
The basic boxplot syntax is:
To get boxplots for each day of the week, side-by-side we rely on the fact the column,
DayOfWeek, is a categorical variable. R calls these
factor variables, and you can confirm this:
TRUE. We can then tell the
boxplot command to group the boxplots by a factor variable. Read the help text,
help(factor) in order to understand more clearly how this plot was generated.
boxplot(website$Visits ~ website$DayOfWeek)