sjmisc (version 1.2)

rec: Recode numeric variables

Description

Recodes the categories of a (numeric) variable x into new category values.

Usage

rec(x, recodes, as.fac = FALSE, var.label = NULL, val.labels = NULL)

Arguments

x

Numeric variable (vector) or a factor with numeric levels that should be recoded; or a data.frame or list of variables.

recodes

String with recode pairs of old and new values. See 'Details' for examples.

as.fac

Logical, if TRUE, recoded variable is returned as factor. Default is FALSE, thus a numeric variable is returned.

var.label

Optional string, to set variable label attribute for the recoded variable (see set_label). If NULL (default), variable label attribute of x will be used (if present).

val.labels

Optional character vector, to set value label attributes of recoded variable (see set_labels). If NULL (default), no value labels will be set.

Value

• A numeric variable (or a factor, if as.fac = TRUE) with recoded category values, or a data frame or list-object with recoded categories for all variables.

Details

The recodes string has following syntax: [object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object],[object Object]

See Also

set_na for setting NA values, replace_na to replace NA's with specific value and recode_to for re-shifting value ranges.

Examples

data(efc)
table(efc$e42dep, exclude = NULL)

# replace NA with 5
table(rec(efc$e42dep, "1=1;2=2;3=3;4=4;NA=5"), exclude = NULL)

# recode 1 to 2 into 1 and 3 to 4 into 2
table(rec(efc$e42dep, "1,2=1; 3,4=2"), exclude = NULL)

# keep value labels. variable label is automatically preserved
str(rec(efc$e42dep,
        "1,2=1; 3,4=2",
        val.labels = c("low dependency", "high dependency")))

# recode 1 to 3 into 4 into 2
table(rec(efc$e42dep, "min:3=1; 4=2"), exclude = NULL)

# recode 2 to 1 and all others into 2
table(rec(efc$e42dep, "2=1; else=2"), exclude = NULL)

# reverse value order
table(rec(efc$e42dep, "rev"), exclude = NULL)

# recode only selected values, copy remaining
table(efc$e15relat)
table(rec(efc$e15relat, "1,2,4=1; else=copy"))

# recode variables with same categorie in a data frame
head(efc[, 6:9])
head(rec(efc[, 6:9], "1=10;2=20;3=30;4=40"))

# recode list of variables. create dummy-list of
# variables with same value-range
dummy <- list(efc$c82cop1, efc$c83cop2, efc$c84cop3)
# show original distribution
lapply(dummy, table, exclude = NULL)
# show recodes
lapply(rec(dummy, "1,2=1; NA=9; else=copy"), table, exclude = NULL)