i_get_equal_subject {ilabelled}

get variable names by subject

Description

return all variable names by subjects

one, several, or all subjects can be looked up

Usage

i_get_equal_subject(x, subject = NULL)

Arguments

x

data.frame

subject

one or more subjects as character vector. when NULL return all variable names by all subjects in data

Value

named list or NA. return named list with one list entry for each subject. when no subject in data or no match for subjects, return NA.