fast_handle_na: Handle NA values

In dataPreparation: Automated Data Preparation

Handle NA values

Description

Handle NAs values depending on the class of the column.

Usage

fast_handle_na(
  data_set,
  set_num = 0,
  set_logical = FALSE,
  set_char = "",
  verbose = TRUE
)

Arguments

data_set	Matrix, data.frame or data.table
set_num	NAs replacement for numeric column, (numeric or function, default to 0)
set_logical	NAs replacement for logical column, (logical or function, default to FALSE)
set_char	NAs replacement for character column, (character or function, default to "")
verbose	Should the algorithm talk (logical, default to TRUE)

Details

To preserve RAM this function edits data_set by reference. To keep object unchanged, please use copy.
If you provide a function, it will be applied to the full column. So this function should handle NAs.
For factor columns, it will add NA to list of values.

Value

data_set as a data.table with NAs replaced.

Examples

# Build a useful data_set set for example
require(data.table)
data_set <- data.table(numCol = c(1, 2, 3, NA),
                   charCol = c("", "a", NA, "c"),
                   booleanCol = c(TRUE, NA, FALSE, NA))

# To set NAs to 0, FALSE and "" (respectively for numeric, logical, character)
fast_handle_na(copy(data_set))

# In a numeric column to set NAs as "missing"
fast_handle_na(copy(data_set), set_char = "missing")

# In a numeric column, to set NAs to the minimum value of the column#'
fast_handle_na(copy(data_set), set_num = min) # Won't work because min(c(1, NA)) = NA so put back NA
fast_handle_na(copy(data_set), set_num = function(x)min(x,na.rm = TRUE)) # Now we handle NAs

# In a numeric column, to set NAs to the share of NAs values
rateNA <- function(x) {
  sum(is.na(x)) / length(x)
}
fast_handle_na(copy(data_set), set_num = rateNA)

dataPreparation documentation built on July 9, 2023, 7:02 p.m.