Change the Column Classes of Variables in a data.frame

Change the column classes of variables in a data.frame that has already been read into your workspace.

toColClasses(inDF, colClasses)

Arguments

inDF	The source data.frame.
colClasses	A character vector of the desired column classes. This should be the same length as the number of columns in the data.frame. If no change is desired, use "".

Value

A data.frame.

Note

This function has only been tested with a very small set of the as.* functions.

References

http://stackoverflow.com/a/18893672/1270695

Author

Ananda Mahto

Examples

mydf <- data.frame(
  a = c(" 1"," 2", " 3"),
  b = c("a","b","c"),
  c = c(" 1.0", "NA", " 2.0"),
  d = c(" 1", "B", "2"),
  e = c(1, 0, 1))

mydf
#>    a b    c  d e
#> 1  1 a  1.0  1 1
#> 2  2 b   NA  B 0
#> 3  3 c  2.0  2 1
str(mydf)
#> 'data.frame':	3 obs. of  5 variables:
#>  $ a: Factor w/ 3 levels " 1"," 2"," 3": 1 2 3
#>  $ b: Factor w/ 3 levels "a","b","c": 1 2 3
#>  $ c: Factor w/ 3 levels " 1.0"," 2.0",..: 1 3 2
#>  $ d: Factor w/ 3 levels " 1","2","B": 1 3 2
#>  $ e: num  1 0 1

x <- toColClasses(mydf, c("as.integer", "", "as.numeric",
                          "as.factor", "as.logical"))
x
#>   a b  c  d     e
#> 1 1 a  1  1  TRUE
#> 2 2 b NA  B FALSE
#> 3 3 c  2  2  TRUE
str(x)
#> 'data.frame':	3 obs. of  5 variables:
#>  $ a: int  1 2 3
#>  $ b: Factor w/ 3 levels "a","b","c": 1 2 3
#>  $ c: num  1 NA 2
#>  $ d: Factor w/ 3 levels " 1","2","B": 1 3 2
#>  $ e: logi  TRUE FALSE TRUE

y <- toColClasses(mydf, c("as.integer", "", "as.numeric",
                          "as.character", "as.logical"))
y
#>   a b  c  d     e
#> 1 1 a  1  1  TRUE
#> 2 2 b NA  B FALSE
#> 3 3 c  2  2  TRUE
str(y)
#> 'data.frame':	3 obs. of  5 variables:
#>  $ a: int  1 2 3
#>  $ b: Factor w/ 3 levels "a","b","c": 1 2 3
#>  $ c: num  1 NA 2
#>  $ d: chr  " 1" "B" "2"
#>  $ e: logi  TRUE FALSE TRUE