R is equipped with many functions for different types of graphs and plots. Such plots are very useful and can provide good insights into the data.
The BoxPlot is a unique and useful graph type. It allows us to study the distribution of data and identify different trends in the dataset. We can use it for comparison between different groups as well.
In R, we generally use the
boxplot() function to create such graphs but we can also make use of the
geom_boxplot() function with the
ggplot() function to create boxplots and there are some other methods available as well.
The following example shows a simple boxplot of three sample distributions using the
v1 <- c(1,2,3,4) v2 <- c(3,4,5,6) v3 <- c(5,6,7,8) boxplot(v1,v2,v3)
We can also label the graph properly using the right parameters. The
xlab parameter labels the x-axis and
ylab parameter labels the y axis. The
main parameter sets the title of the graph. We can label the different groups present in the plot using the
names parameter. The following code and graph will show the use of all these parameters.
boxplot(v1,v2,v3, main = "Sample Graph", xlab = "X Values", ylab = "Y Values", names = c("First","Second","Third"))
Notice the difference in both the graphs with the addition of labels in the second graph.
We can also add the
notch parameter and set it to
TRUE to add a notch to the boxes and help in studying the medians of data. To make the boxes on the other axis, we can set the
horizontal parameter to be
boxplot(v1,v2,v3, main = "Sample Graph", xlab = "X Values", ylab = "Y Values", names = c("First","Second","Third"), notch = TRUE, horizontal = TRUE)