Read embedded XML metadata from a NESSTAR container

Decodes the Huffman-compressed XML blocks embedded in the container to recover dataset file names, variable labels, and categorical value labels.

Usage

nesstar_metadata(x)

Arguments

x

A nesstar_binary object from nesstar_parse.

Value

A named list:

datasets

A list, one element per dataset, each containing dataset_number, file_name, and variables (a list of per-variable lists with name, label, and categories).

Returns NULL (with a warning) when metadata cannot be decoded.

Details

If the embedded metadata blocks cannot be decoded (e.g. older NSS files where record IDs differ) the function returns NULL with a warning instead of stopping.