map_values: Map values of variables.

In rtsho/preprocessr: Functions to make your preprocessing life easier.

Description

Map values of variables.

Usage

map_values(vars, mapping, rename)

Arguments

vars	Function or formula that returns selected columns from a data.frame. Alternatively, character vector of column names.
mapping	The mapping to apply. This should be a named vector, where the names are the old values, and the elements are the new values. There should be at most one unnamed element, representing 'all other' elements.
func	Function to do the imputation (e.g. mean, median). Can be a user defined function or a formula, where a dot represents the column.

Details

Currently, this function always turns the mapped variables into factors.

Examples

df <- data.frame(a=c(1,2,NA,3), b=c(10,20,30,NA), c=c("c1", "c2", "c3", "c4"))
prep <- map_values("c", c(c1="C1", c4="C4", "other"))
prep$fit(df)
prep$transform(df)
# or more succintly
prep$fit_transform(df)

rtsho/preprocessr documentation built on May 29, 2019, 8:58 a.m.