Example: Coercion

Data types

Coercion of data elements into one of the basic R data types is straight forward. Just add “as.” to the data type to obtain the respective function.

x <- c(1.4, 2.5, 3.6, 4.0)
class(x)

## [1] "numeric"

as.character(x)

## [1] "1.4" "2.5" "3.6" "4"

as.integer(x)

## [1] 1 2 3 4

as.factor(x)

## [1] 1.4 2.5 3.6 4  
## Levels: 1.4 2.5 3.6 4

Please note that the as.integer function returns the floor of the floating point values and does not apply any rounding rules.

Data structures

So far, we have differentiated between data types and structures. Actually, a vector, list or data frame is nothing but another data type and the same logic of conversion functions can be used.

x <- c(1.4, 2.5, 3.6, 4.0)
class(x) # i.e. vector of type numeric

## [1] "numeric"

as.list(x)

## [[1]]
## [1] 1.4
## 
## [[2]]
## [1] 2.5
## 
## [[3]]
## [1] 3.6
## 
## [[4]]
## [1] 4

as.data.frame(x)

##     x
## 1 1.4
## 2 2.5
## 3 3.6
## 4 4.0

as.matrix(x)

##      [,1]
## [1,]  1.4
## [2,]  2.5
## [3,]  3.6
## [4,]  4.0