createLookup: Extract values for recoding.

In eatGADS: Data Management of Large Hierarchical Data

Extract values for recoding.

Description

Extract unique values from one or multiple variables of a GADSdat object for recoding (e.g. via an Excel spreadsheet).

Usage

createLookup(GADSdat, recodeVars, sort_by = NULL, addCols = c("value_new"))

Arguments

GADSdat	A GADSdat object.
recodeVars	Character vector of variable names which should be recoded.
sort_by	By which column (variable and/or value) should the long format data.frame be sorted? If NULL, no sorting is performed.
addCols	Character vector of additional column names for recoding purposes.

Details

If recoding of one or multiple variables is more complex, a lookup table can be created for later application via applyLookup or applyLookup_expandVar. The function allows the extraction of the values of multiple variables and sorting of these unique values via variable and/or values. If addCols are specified the lookup table has to be formatted via collapseColumns, before it can be applied to recode data.

Value

Returns a data frame in long format with the following variables:

variable	Variables as specified in recodeVars
value	Unique values of the variables specified in recodeVars
value_new	This is the default for addCols. If different additional column names are supplied, this column is missing.

Examples

# create example GADS
dat <- data.frame(ID = 1:4, var1 = c(NA, "Eng", "Aus", "Aus2"),
                  var2 = c(NA, "French", "Ger", "Ita"),
                  stringsAsFactors = FALSE)
gads <- import_DF(dat)

# create Lookup table for recoding
lookup <- createLookup(gads, recodeVars = c("var1", "var2"), sort_by = c("value", "variable"))

# create Lookup table for recoding by multiple recoders
lookup2 <- createLookup(gads, recodeVars = c("var1", "var2"), sort_by = c("value", "variable"),
                        addCols = c("value_recoder1", "value_recoder2"))

eatGADS documentation built on Oct. 9, 2024, 5:09 p.m.