tidywikidatar (version 0.6.2)

tw_get_qualifiers: Get Wikidata qualifiers for a given property of a given item

Description

N.B. In order to provide for consistently structured output, this function outputs either id or value for each qualifier. The user should keep in mind that some of these come with additional detail (e.g. the unit, precision, or reference calendar).

Usage

tw_get_qualifiers(
  id,
  p,
  language = tidywikidatar::tw_get_language(),
  cache = NULL,
  overwrite_cache = FALSE,
  cache_connection = NULL,
  disconnect_db = TRUE,
  wait = 0,
  retry = 10,
  user_agent = tidywikidatar::tw_get_user_agent(),
  id_l = NULL
)

Value

A data frame (a tibble) with eight columns: id for the input id, property, qualifier_id, qualifier_property, qualifier_value, rank, qualifier_value_type, and set (to distinguish sets of data when a property is present more than once)

Arguments

id

A character vector, must start with Q, e.g. "Q180099" for the anthropologist Margaret Mead. Can also be a data frame of one row, typically generated with tw_search() or a combination of tw_search() and tw_filter_first().

p

A character vector, a property. Must always start with the capital letter "P", e.g. "P31" for "instance of".

language

Defaults to language set with tw_set_language(); if not set, "en". Use "all_available" to keep all languages. For available language values, see the dedicated Wikimedia page.

cache

Defaults to NULL. If given, it should be given either TRUE or FALSE. Typically set with tw_enable_cache() or tw_disable_cache().

overwrite_cache

Logical, defaults to FALSE. If TRUE, it overwrites the table in the local sqlite database. Useful if the original Wikidata object has been updated.

cache_connection

Defaults to NULL. If NULL, and caching is enabled, tidywikidatar will use a local sqlite database. A custom connection to other databases can be given (see vignette caching for details).

disconnect_db

Defaults to TRUE. If FALSE, leaves the connection to cache open.

wait

In seconds, defaults to 0. Time to wait between queries to Wikidata. If data are cached locally, wait time is not applied. If you are running many queries systematically you may want to add some waiting time between queries.

retry

Defaults to 10. Maximum number of times to retry if the API throws an error, such as "too many requests". Each time, it will wait as much time as requested by the API. Notice that this can be a long time, e.g. 30 minutes. Set to FALSE if you prefer the API to throw an error immediately. Consider adjusting the wait parameter, or customising the user_agent if relevant.

user_agent

Defaults to NULL. If not given, implicitly defaults to current package name (tidywikidatar) and version.

id_l

Defaults to NULL. If given, must be an object or list such as the one generated with tw_get_item(). If given, and the requested id is actually present in id_l, then no query to Wikidata servers is made.

Examples

if (interactive()) {
  tidywikidatar::tw_get_qualifiers(id = "Q180099", p = "P26", language = "en")
}

#' ## using `tw_test_items` in examples in order to show output without calling
## on Wikidata servers

tidywikidatar::tw_get_qualifiers(
  id = "Q180099",
  p = "P26",
  language = "en",
  id_l = tw_test_items
)