Recode values of a vector

Recodes a vector with values, say 1,2 to a variable with values, say 'a', 'b'

recodeVar(x, src, tgt, default = NULL, keep.na = TRUE)

recode_var(x, src, tgt, default = NULL, keep.na = TRUE)

Arguments

x

A vector; the variable to be recoded.

src

The source values: a subset of the present values of x

tgt

The target values: the corresponding new values of x

default

Default target value for those values of x not listed in src. When default=NULL, values of x which are not given in src will be kept in the output.

keep.na

If TRUE then NA's in x will be retained in the output

Value

A vector

Warning

Care should be taken if x is a factor. A safe approach may be to convert x to a character vector using as.character.

See also

cut, factor, recodeVar

Author

Søren Højsgaard, sorenh@math.aau.dk

Examples

x <- c("dec", "jan", "feb", "mar", "apr", "may")
src1 <- list(c("dec", "jan", "feb"), c("mar", "apr", "may"))
tgt1 <- list("winter", "spring")
recodeVar(x, src=src1, tgt=tgt1)
#> [1] "winter" "winter" "winter" "spring" "spring" "spring"
#[1] "winter" "winter" "winter" "spring" "spring" "spring"

x <- c(rep(1:3, 3))
#[1] 1 2 3 1 2 3 1 2 3

## Simple usage:
recodeVar(x, src=c(1, 2), tgt=c("A", "B"))
#> [1] "A" "B" "3" "A" "B" "3" "A" "B" "3"
#[1] "A" "B" NA  "A" "B" NA  "A" "B" NA 

## Here we need to use lists
recodeVar(x, src=list(c(1, 2)), tgt=list("A"))
#> [1] "A" "A" "3" "A" "A" "3" "A" "A" "3"
#[1] "A" "A" NA  "A" "A" NA  "A" "A" NA 
recodeVar(x, src=list(c(1, 2)), tgt=list("A"), default="L")
#> [1] "A" "A" "L" "A" "A" "L" "A" "A" "L"
#[1] "A" "A" "L" "A" "A" "L" "A" "A" "L"
recodeVar(x, src=list(c(1, 2), 3), tgt=list("A", "B"), default="L")
#> [1] "A" "A" "B" "A" "A" "B" "A" "A" "B"
#[1] "A" "A" "B" "A" "A" "B" "A" "A" "B"

## Dealing with NA's in x
x<-c(NA,rep(1:3, 3),NA)
#[1] NA  1  2  3  1  2  3  1  2  3 NA
recodeVar(x, src=list(c(1, 2)), tgt=list("A"))
#>  [1] NA  "A" "A" "3" "A" "A" "3" "A" "A" "3" NA 
#[1] NA  "A" "A" NA  "A" "A" NA  "A" "A" NA  NA 
recodeVar(x, src=list(c(1, 2)), tgt=list("A"), default="L")
#>  [1] NA  "A" "A" "L" "A" "A" "L" "A" "A" "L" NA 
#[1] NA  "A" "A" "L" "A" "A" "L" "A" "A" "L" NA 
recodeVar(x, src=list(c(1, 2)), tgt=list("A"), default="L", keep.na=FALSE)
#>  [1] "L" "A" "A" "L" "A" "A" "L" "A" "A" "L" "L"
#[1] "L" "A" "A" "L" "A" "A" "L" "A" "A" "L" "L"

x <- c("no", "yes", "not registered", "no", "yes", "no answer")
recodeVar(x, src = c("no", "yes"), tgt = c("0", "1"), default = NA)
#> [1] "0" "1" NA  "0" "1" NA