The tabulate() function in R can be used to count the occurrences of integer values in a vector.
This function uses the following basic syntax:
tabulate(bin, nbins=max(1, bin, na.rm=TRUE))
where:
- bin: Name of the vector
- nbins: The number of bins to be used
The following examples show how to use this function in practice.
Example 1: Count Integer Occurrences in Vector
The following code shows how to use the tabulate() function to count the occurrences of integers in a given vector:
#create vector of data values
data #count occurrences of integers in vector
tabulate(data)
[1] 3 1 3 1 0 0 1 1
By default, the tabulate() function uses 1 as the minimum integer value and displays the occurrences of each successive integer in the vector.
For example:
- The integer 1 occurs 3 times in the vector.
- The integer 2 occurs 1 time in the vector.
- The integer 3 occurs 3 times in the vector.
- The integer 4 occurs 1 time in the vector.
- The integer 5 occurs 0 times in the vector.
And so on.
Note that if you use the nbins argument, you simply limit the number of integers that the tabulate() function counts:
#count occurrences of integers but limit output to 5 tabulate(data, nbins=5) [1] 3 1 3 1 0
Example 2: Count Integer Occurrences in Vector with Decimals
If we use the tabulate() function with a vector that contains decimals, the function will simply tell us how often each integer value occurs:
#create vector of data values with decimals
data #count occurrences of integers
tabulate(data)
[1] 3 1 2
From the output we can see:
- The integer value 1 occurred 3 times.
- The integer value 2 occurred 1 time.
- The integer value 3 occurred 2 times.
Example 3: Count Integer Occurrences in Vector with Negative Values
If we use the tabulate() function with a vector that contains negative values or zeros, the function will simply ignore the negative values and the zeros:
#create vector with some negative values and zeros
data #count occurrences of integers
tabulate(data)
[1] 2 1 0 1
From the output we can see:
- The integer value 1 occurred 2 times.
- The integer value 2 occurred 1 time.
- The integer value 3 occurred 0 times.
- The integer value 4 occurred 1 time.
An Alternative to Tabulate: The table() Function
If you’d like to count the occurrence of every value in a vector, it’s better to use the table() function:
#create vector with a variety of numbers
data #count occurrences of each unique value in vector
table(data)
data
-5 -2 0 1 2.5 4
2 1 1 2 1 1
From the output we can see:
- The value -5 occurred 2 times.
- The value -2 occurred 1 time.
- The value 0 occurred 1 time.
- The value 1 occurred 2 times.
- The value 2.5 occurred 1 time.
- The value 4 occurred 1 time.
Notice that the table() function counts the occurrence of every value, not just the integer values.
Additional Resources
The following tutorials explain how to use other common functions in R:
How to Use summary() Function in R
How to Use the replicate() Function in R
How to Use match() Function in R