Get the imputation methods for the intervals

get_impute_method() is the rule pk.nca() uses to find the imputation methods for each interval, from the impute argument of PKNCAdata() and the intervals. It reads impute one of three ways, in this order:

Usage

get_impute_method(intervals, impute)

Arguments

intervals

the data.frame of intervals

impute

the imputation definition – either the name of a column in intervals (character scalar), NA to look for a generic "impute" column, or the imputation method string. Must be an atomic scalar; a list (even of length 1) is rejected.

Value

A character vector of imputation specifications: one per row of intervals when read from a column, and of length one otherwise (the method string, or NA_character_ for no imputation). A column that is not character is an error, except that a column of only NA (which is logical when made with NA) is read as no imputation.

Details

1. If impute is the name of a column in intervals, the methods are that column's values, one per interval. The name may be any column name, not only "impute".

2. Otherwise, if impute is NA and intervals has a column named "impute", the methods are that column's values, one per interval.

3. Otherwise impute is itself the method (or comma- or space-separated methods) for every interval, and the result is impute as a single value. An NA that finds no "impute" column therefore gives a single NA_character_, meaning no imputation.

get_impute_method() only reads the specification. It does not check that the methods exist; assert_impute_method() does. get_impute_column() gives the name of the column the methods are read from, which tells a column from a method string even for an intervals table with one row.

See also

Other Imputation: PKNCA_impute_fun_list(), PKNCA_impute_method, assert_impute_method(), get_impute_column(), pknca_impute_methods()

Examples

intervals <- data.frame(start = 0, end = 24, impute = "start_conc0")
# The column named by `impute`
get_impute_method(intervals, impute = "impute")
#> [1] "start_conc0"
# NA finds the column named "impute"
get_impute_method(intervals, impute = NA)
#> [1] "start_conc0"
# NA without an "impute" column means no imputation
get_impute_method(intervals[, c("start", "end")], impute = NA)
#> [1] NA
# Anything else is the method for every interval
get_impute_method(intervals, impute = "start_predose")
#> [1] "start_predose"