This function replaces specific values of variables with NA.
set_na(x, ..., na, drop.levels = TRUE, as.tag = FALSE)A vector or data frame.
Optional, unquoted names of variables that should be selected for
further processing. Required, if x is a data frame (and no
vector) and only selected variables from x should be processed.
You may also use functions like : or tidyselect's select-helpers.
See 'Examples'.
Numeric vector with values that should be replaced with NA values,
or a character vector if values of factors or character vectors should be
replaced. For labelled vectors, may also be the name of a value label. In
this case, the associated values for the value labels in each vector
will be replaced with NA. na can also be a named vector.
If as.tag = FALSE, values will be replaced only in those variables
that are indicated by the value names (see 'Examples').
Logical, if TRUE, factor levels of values that have
been replaced with NA are dropped. See 'Examples'.
Logical, if TRUE, values in x will be replaced
by tagged_na, else by usual NA values. Use a named
vector to assign the value label to the tagged NA value (see 'Examples').
x, with all values in na being replaced by NA.
If x is a data frame, the complete data frame x will
be returned, with NA's set for variables specified in ...;
if ... is not specified, applies to all variables in the
data frame.
set_na() converts all values defined in na with
a related NA or tagged NA value (see tagged_na()).
Tagged NAs work exactly like regular R missing values
except that they store one additional byte of information: a tag,
which is usually a letter ("a" to "z") or character number ("0" to "9").
Different NA values for different variables
If na is a named vector and as.tag = FALSE, the names
indicate variable names, and the associated values indicate those values
that should be replaced by NA in the related variable. For instance,
set_na(x, na = c(v1 = 4, v2 = 3)) would replace all 4 in v1
with NA and all 3 in v2 with NA.
If na is a named list and as.tag = FALSE, it is possible
to replace different multiple values by NA for different variables
separately. For example, set_na(x, na = list(v1 = c(1, 4), v2 = 5:7))
would replace all 1 and 4 in v1 with NA and all 5 to 7 in
v2 with NA.
Furthermore, see also 'Details' in get_na.
Labels from values that are replaced with NA and no longer used will be
removed from x, however, other value and variable label
attributes are preserved. For more details on labelled data,
see vignette Labelled Data and the sjlabelled-Package.
if (require("sjmisc") && require("dplyr") && require("haven")) {
# create random variable
dummy <- sample(1:8, 100, replace = TRUE)
# show value distribution
table(dummy)
# set value 1 and 8 as missings
dummy <- set_na(dummy, na = c(1, 8))
# show value distribution, including missings
table(dummy, useNA = "always")
# add named vector as further missing value
set_na(dummy, na = c("Refused" = 5), as.tag = TRUE)
# see different missing types
print_tagged_na(set_na(dummy, na = c("Refused" = 5), as.tag = TRUE))
# create sample data frame
dummy <- data.frame(var1 = sample(1:8, 100, replace = TRUE),
var2 = sample(1:10, 100, replace = TRUE),
var3 = sample(1:6, 100, replace = TRUE))
# set value 2 and 4 as missings
dummy %>% set_na(na = c(2, 4)) %>% head()
dummy %>% set_na(na = c(2, 4), as.tag = TRUE) %>% get_na()
dummy %>% set_na(na = c(2, 4), as.tag = TRUE) %>% get_values()
data(efc)
dummy <- data.frame(
var1 = efc$c82cop1,
var2 = efc$c83cop2,
var3 = efc$c84cop3
)
# check original distribution of categories
lapply(dummy, table, useNA = "always")
# set 3 to NA for two variables
lapply(set_na(dummy, var1, var3, na = 3), table, useNA = "always")
# if 'na' is a named vector *and* 'as.tag = FALSE', different NA-values
# can be specified for each variable
set.seed(1)
dummy <- data.frame(
var1 = sample(1:8, 10, replace = TRUE),
var2 = sample(1:10, 10, replace = TRUE),
var3 = sample(1:6, 10, replace = TRUE)
)
dummy
# Replace "3" in var1 with NA, "5" in var2 and "6" in var3
set_na(dummy, na = c(var1 = 3, var2 = 5, var3 = 6))
# if 'na' is a named list *and* 'as.tag = FALSE', for each
# variable different multiple NA-values can be specified
set_na(dummy, na = list(var1 = 1:3, var2 = c(7, 8), var3 = 6))
# drop unused factor levels when being set to NA
x <- factor(c("a", "b", "c"))
x
set_na(x, na = "b", as.tag = TRUE)
set_na(x, na = "b", drop.levels = FALSE, as.tag = TRUE)
# set_na() can also remove a missing by defining the value label
# of the value that should be replaced with NA. This is in particular
# helpful if a certain category should be set as NA, however, this category
# is assigned with different values accross variables
x1 <- sample(1:4, 20, replace = TRUE)
x2 <- sample(1:7, 20, replace = TRUE)
x1 <- set_labels(x1, labels = c("Refused" = 3, "No answer" = 4))
x2 <- set_labels(x2, labels = c("Refused" = 6, "No answer" = 7))
tmp <- data.frame(x1, x2)
get_labels(tmp)
table(tmp, useNA = "always")
get_labels(set_na(tmp, na = "No answer"))
table(set_na(tmp, na = "No answer"), useNA = "always")
# show values
tmp
set_na(tmp, na = c("Refused", "No answer"))
}
#> [1] NA(5) 3 6 6 2 4 7 4 NA(5) NA(5) NA(5) NA
#> [13] NA(5) 4 NA 2 4 3 NA 6 6 2 3 7
#> [25] NA 3 NA NA NA NA(5) NA 4 3 NA 2 NA
#> [37] NA NA NA 6 2 6 NA 3 NA(5) NA NA 6
#> [49] NA(5) 2 NA 6 NA 4 6 6 NA 3 3 3
#> [61] NA NA 3 NA 6 2 2 NA(5) NA(5) NA 2 2
#> [73] NA NA 4 NA 3 NA NA(5) NA(5) NA 2 3 2
#> [85] NA NA NA NA(5) 6 7 NA(5) 2 4 7 2 NA(5)
#> [97] 4 7 2 2
#> x1 x2
#> 1 NA 4
#> 2 NA 1
#> 3 1 NA
#> 4 NA NA
#> 5 NA 2
#> 6 2 NA
#> 7 2 3
#> 8 2 2
#> 9 2 NA
#> 10 NA NA
#> 11 NA 2
#> 12 NA 5
#> 13 NA 2
#> 14 2 NA
#> 15 NA NA
#> 16 1 NA
#> 17 NA 1
#> 18 2 3
#> 19 1 3
#> 20 NA NA