In this recipe, we will learn how to plot formatted date or time values on the x axis.
We will use the dailysales.csv
example dataset to plot the number of units of a product sold daily in a month:
sales<-read.csv("dailysales.csv") plot(sales$units~as.Date(sales$date,"%d/%m/%y"),type="l", xlab="Date",ylab="Units Sold")
Once we have formatted the series of dates using as.Date()
, we can simply pass it to the plot()
function as the x
variable in either the plot(x,y)
or plot(y~x)
format.
We can also use strptime()
instead of using as.Date()
. However, we cannot pass the object returned by strptime()
to plot()
in the plot(y~x)
format. We must use the plot(x,y)
format as follows:
plot(strptime(sales$date,"%d/%m/%Y"),sales$units,type="l", xlab="Date",ylab="Units Sold")