# recode: Change, rearrange or consolidate the values of an existing or... In expss: Tables, Labels and Some Useful Functions from Spreadsheets and 'SPSS' Statistics

## Description

`recode` change, rearrange or consolidate the values of an existing variable based on conditions. Design of this function inspired by RECODE from SPSS. Sequence of recodings provided in the form of formulas. For example, 1:2 ~ 1 means that all 1's and 2's will be replaced with 1. Each value will be recoded only once. In the assignment form `recode(...) = ...` of this function values which doesn't meet any condition remain unchanged. In case of the usual form `... = recode(...)` values which doesn't meet any condition will be replaced with NA. One can use values or more sophisticated logical conditions and functions as a condition. There are several special functions for usage as criteria - for details see criteria. Simple common usage looks like: `recode(x, 1:2 ~ -1, 3 ~ 0, 1:2 ~ 1, 99 ~ NA)`. For more information, see details and examples. The `ifs` function checks whether one or more conditions are met and returns a value that corresponds to the first TRUE condition. `ifs` can take the place of multiple nested `ifelse` statements and is much easier to read with multiple conditions. `ifs` works in the same manner as `recode` - e. g. with formulas. But conditions should be only logical and it doesn't operate on multicolumn objects.

## Usage

 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24``` ```recode( x, ..., with_labels = FALSE, new_label = c("all", "range", "first", "last") ) rec(x, ..., with_labels = TRUE, new_label = c("all", "range", "first", "last")) recode(x, with_labels = FALSE, new_label = c("all", "range", "first", "last")) <- value rec(x, with_labels = TRUE, new_label = c("all", "range", "first", "last")) <- value ifs(...) lo hi copy(x) from_to(from, to) values %into% names ```

## Arguments

 `x` vector/matrix/data.frame/list `...` sequence of formulas which describe recodings. They are used when `from`/`to` arguments are not provided. `with_labels` logical. FALSE by default for 'recode' and TRUE for 'rec'. Should we also recode value labels with the same recodings as variable? `new_label` one of "all", "range", "first", or "last". If we recode value labels ('with_labels = TRUE') how we will combine labels for duplicated values? "all" will use all labels, "range" will use first and last labels. See examples. `value` list with formulas which describe recodings in assignment form of function/`to` list if `from`/`to` notation is used. `from` list of conditions for values which should be recoded (in the same format as LHS of formulas). `to` list of values into which old values should be recoded (in the same format as RHS of formulas). `values` object(-s) which will be assigned to `names` for `%into%` operation. `%into%` supports multivalue assignments. See examples. `names` name(-s) which will be given to `values` expression. For `%into%`.

## Format

An object of class `numeric` of length 1.

An object of class `numeric` of length 1.

## Details

Input conditions - possible values for left-hand side (LHS) of formula or element of `from` list:

• vector/single value All values in `x` which equal to elements of the vector in LHS will be replaced with RHS.

• function Values for which function gives TRUE will be replaced with RHS. There are some special functions for the convenience - see criteria.

• single logical value `TRUE` It means all other unrecoded values (ELSE in SPSS RECODE). All other unrecoded values will be changed to RHS of the formula or appropriate element of `to`.

Output values - possible values for right-hand side (RHS) of formula or element of `to` list:

• value replace elements of `x`. This value will be recycled across rows and columns of `x`.

• vector values of this vector will replace values in the corresponding position in rows of `x`. Vector will be recycled across columns of `x`.

• function This function will be applied to values of `x` which satisfy recoding condition. There is a special auxiliary function `copy` which just returns its argument. So, in the `recode` it just copies old value (COPY in SPSS RECODE). See examples.

`%into%` tries to mimic SPSS 'INTO'. Values from left-hand side will be assigned to right-hand side. You can use `%to%` expression in the RHS of `%into%`. See examples. `lo` and `hi` are shortcuts for `-Inf` and `Inf`. They can be useful in expressions with `%thru%`, e. g. ```1 %thru% hi```.

## Value

object of the same form as `x` with recoded values

## Examples

 ``` 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102``` ```# examples from SPSS manual # RECODE V1 TO V3 (0=1) (1=0) (2, 3=-1) (9=9) (ELSE=SYSMIS) v1 = c(0, 1, 2, 3, 9, 10) recode(v1) = c(0 ~ 1, 1 ~ 0, 2:3 ~ -1, 9 ~ 9, TRUE ~ NA) v1 # RECODE QVAR(1 THRU 5=1)(6 THRU 10=2)(11 THRU HI=3)(ELSE=0). qvar = c(1:20, 97, NA, NA) recode(qvar, 1 %thru% 5 ~ 1, 6 %thru% 10 ~ 2, 11 %thru% hi ~ 3, TRUE ~ 0) # the same result recode(qvar, 1 %thru% 5 ~ 1, 6 %thru% 10 ~ 2, ge(11) ~ 3, TRUE ~ 0) # RECODE STRNGVAR ('A', 'B', 'C'='A')('D', 'E', 'F'='B')(ELSE=' '). strngvar = LETTERS recode(strngvar, c('A', 'B', 'C') ~ 'A', c('D', 'E', 'F') ~ 'B', TRUE ~ ' ') # recode in place. Note that we recode only first six letters recode(strngvar) = c(c('A', 'B', 'C') ~ 'A', c('D', 'E', 'F') ~ 'B') strngvar # RECODE AGE (MISSING=9) (18 THRU HI=1) (0 THRU 18=0) INTO VOTER. age = c(NA, 2:40, NA) voter = recode(age, NA ~ 9, 18 %thru% hi ~ 1, 0 %thru% 18 ~ 0) voter # the same result with '%into%' recode(age, NA ~ 9, 18 %thru% hi ~ 1, 0 %thru% 18 ~ 0) %into% voter2 voter2 # recode with adding labels voter = recode(age, "Refuse to answer" = NA ~ 9, "Vote" = 18 %thru% hi ~ 1, "Don't vote" = 0 %thru% 18 ~ 0) voter # recoding with labels ol = c(1:7, 99) var_lab(ol) = "Liking" val_lab(ol) = num_lab(" 1 Disgusting 2 Very Poor 3 Poor 4 So-so 5 Good 6 Very good 7 Excellent 99 Hard to say ") recode(ol, 1:3 ~ 1, 5:7 ~ 7, TRUE ~ copy, with_labels = TRUE) # 'rec' is a shortcut for recoding with labels. Same result: rec(ol, 1:3 ~ 1, 5:7 ~ 7, TRUE ~ copy) # another method of combining labels recode(ol, 1:3 ~ 1, 5:7 ~ 7, TRUE ~ copy, with_labels = TRUE, new_label = "range") # example with from/to notation # RECODE QVAR(1 THRU 5=1)(6 THRU 10=2)(11 THRU HI=3)(ELSE=0). list_from = list(1 %thru% 5, 6 %thru% 10, ge(11), TRUE) list_to = list(1, 2, 3, 0) recode(qvar, from_to(list_from, list_to)) list_from = list(NA, 18 %thru% hi, 0 %thru% 18) list_to = list("Refuse to answer" = 9, "Vote" = 1, "Don't vote" = 0) voter = recode(age, from_to(list_from, list_to)) voter # 'ifs' examples a = 1:5 b = 5:1 ifs(b>3 ~ 1) # c(1, 1, NA, NA, NA) ifs(b>3 ~ 1, TRUE ~ 3) # c(1, 1, 3, 3, 3) ifs(b>3 ~ 1, a>4 ~ 7, TRUE ~ 3) # c(1, 1, 3, 3, 7) ifs(b>3 ~ a, TRUE ~ 42) # c(1, 2, 42, 42, 42) # advanced usage #' # multiple assignment with '%into%' set.seed(123) x1 = runif(30) x2 = runif(30) x3 = runif(30) # note nessesary brackets around RHS of '%into%' recode(x1 %to% x3, gt(0.5) ~ 1, other ~ 0) %into% (x_rec_1 %to% x_rec_3) fre(x_rec_1) # the same operation with characters expansion i = 1:3 recode(x1 %to% x3, gt(0.5) ~ 1, other ~ 0) %into% text_expand('x_rec2_{i}') fre(x_rec2_1) # factor recoding a = factor(letters[1:4]) recode(a, "a" ~ "z", TRUE ~ copy) # we get factor # example with function in RHS data(iris) new_iris = recode(iris, is.numeric ~ scale, other ~ copy) str(new_iris) set.seed(123) a = rnorm(20) # if a<(-0.5) we change it to absolute value of a (abs function) recode(a, lt(-0.5) ~ abs, other ~ copy) # the same example with logical criteria recode(a, when(a<(-.5)) ~ abs, other ~ copy) ```

expss documentation built on Jan. 8, 2021, 5:38 p.m.