The table() function in R is used to create… a table. So far, so good. In fact, this is a rather simple function that gathers data and creates a contingency table or frequency table, in other words, a table which counts the number of occurrences of any unique value in a data set. Let’s check the following example where we store a random a random list of numbers in the range 1:5.
[code language=”r”]
random.list <- c(1,5,3,4,2,5,4,3,1,2,4,5,1,3,2,4,5,1,2,3,1,4,5,2,3,1,5,5,2,1)
random.list
table(random.list)
[/code]
The function table() counts how many “1”, “2”, “3”, “4” and “5” are in the object random.list and provides a very simple frequency table where we can read for instance that the number 3 is found five times and the number 5 is found seven times.