R: Numbers

In general, numbers in R are treated as numeric objects.

For example,

 3 # numeric object
[1] 3
 3L # explicitly gives an integer
[1] 3
 Inf # a special number which represents infinity
[1] Inf
 1/0
[1] Inf
 1/Inf # can be used in calculations
[1] 0
 0/0 # NaN ("not a number"); also, seen as a missing number
[1] NaN

 

Numerics are also decimal values in R. This happens by default, so that if you create a decimal value for x that is will be of the numeric type.

 x = 8.3 # create x which a decimal value
 x # print the value of x
[1] 8.3
 class(x) # what is the class of x?
[1] "numeric"

 

Even when assigning an integer to a variable such as N, it is still being retained as a numeric value.

 N = 43
 N #print the value of N
[1] 43
 class(N) # what is the class of N?
[1] "numeric"

 

You can further confirm that N is not an integer by using the is.integer function.

 is.integer(N) # is N an integer?
[1] FALSE
 is.numeric(N) # is N numeric?
[1] TRUE