data_dict_expand: Transform single-row category information to multiple rows as element

Description

Expands data dictionary column(s) in a element (the parameter 'from'), into another element (the parameter 'to'). If the element from contains any column starting with 'prefix', (xx,yy), these columns will be added as 'xx' and 'yy' in the element identified by to. This data frame will be created if necessary, and columns will be added, from left to right. (unique names will be generated if necessary). Separator of each element is the following structure : 'name = xx1 ; name = xx2'. This function is mainly used to expand the column(s) 'Categories::xx' in "Variables" to "Categories" element with column(s) xx. This function is the reversed operation of data_dict_collapse()

Usage

data_dict_expand(
  data_dict,
  from = "Variables",
  name_prefix = "Categories::",
  to = "Categories"
)

Value

A list of data frame(s) identifying a data dictionary.

Arguments

data_dict: A list of data frame(s) representing metadata to be transformed.
from: A symbol identifying the name of the element (data frame) to take column(s) from. Default is 'Variables'.
name_prefix: Character string of the prefix of columns of interest. This prefix will be used to select columns, and to rename them in the 'to' element. Default is 'Categories::'.
to: A symbol identifying the name of the element (data frame) to create column(s) to. Default is 'Categories'.

Details

A data dictionary contains the list of variables in a dataset and metadata about the variables and can be associated with a dataset. A data dictionary object is a list of data frame(s) named 'Variables' (required) and 'Categories' (if any). To be usable in any function, the data frame 'Variables' must contain at least the name column, with all unique and non-missing entries, and the data frame 'Categories' must contain at least the variable and name columns, with unique combination of variable and name.

Examples

Run this code

{

library(dplyr)

# use madshapR_examples provided by the package
data_dict_collapsed <- madshapR_examples$`data_dictionary_example - collapsed`

data_dict_expanded <- data_dict_expand(data_dict_collapsed)
glimpse(data_dict_expand(data_dict_expanded))

}