polmineR: s_attributes-method – R documentation

Become an expert in R — Interactive courses, Cheat Sheets, certificates and more!

s_attributes-method

Get s-attributes.

Description

Structural annotations (s-attributes) of a corpus capture metainformation for regions of tokens. The s_attributes-method offers high-level access to the s-attributes present in a corpus or subcorpus, or the values of s-attributes in a corpus/partition.

Usage

s_attributes(.Object, ...)

## S4 method for signature 'character'
s_attributes(.Object, s_attribute = NULL, unique = TRUE, regex = NULL, ...)

## S4 method for signature 'corpus'
s_attributes(.Object, s_attribute = NULL, unique = TRUE, regex = NULL, ...)

## S4 method for signature 'slice'
s_attributes(.Object, s_attribute = NULL, unique = TRUE, ...)

## S4 method for signature 'partition'
s_attributes(.Object, s_attribute = NULL, unique = TRUE, ...)

## S4 method for signature 'subcorpus'
s_attributes(.Object, s_attribute = NULL, unique = TRUE, ...)

## S4 method for signature 'call'
s_attributes(.Object, corpus)

## S4 method for signature 'remote_corpus'
s_attributes(.Object, ...)

## S4 method for signature 'remote_partition'
s_attributes(.Object, ...)

Arguments

`.Object`	A `corpus`, `subcorpus`, `partition` object, or a `call`. A corpus can also be specified by a length-one `character` vector.
`...`	To maintain backward compatibility, if argument `sAttribute` (deprecated) is used. If `.Object` is a `remote_corpus` or `remote_subcorpus` object, the three dots (`...`) are used to pass arguments. Hence, it is necessary to state the names of all arguments to be passed explicity.
`s_attribute`	The name of a specific s-attribute.
`unique`	A `logical` value, whether to return unique values.
`regex`	A regular expression passed into `grep` to filter return value by applying a regex.
`corpus`	A `corpus`-object or a length one character vector denoting a corpus.

Details

Importing XML into the Corpus Workbench (CWB) turns elements and element attributes into so-called "s-attributes". There are two basic uses of the s_attributes-method: If the argument s_attribute is NULL (default), the return value is a character vector with all s-attributes present in a corpus.

If s_attribute is the name of a specific s-attribute (a length-one character vector), the values of the s-attributes available in the corpus/partition are returned.

If argument unique is FALSE, the full sequence of the s_attributes is returned, which is a useful building block for decoding a corpus.

If argument s_attributes is a character providing several s-attributes, the method will return a data.table. If unique is TRUE, all unique combinations of the s-attributes will be reported by the data.table.

If .Object is a call, the s_attributes-method will return a character vector with the s-attributes occurring in the call. This usage is relevant internally to implement the subset method to generate a subcorpus using non-standard evaluation. Usually it will not be relevant in an interactive session.

Value

A character vector (s-attributes, or values of s-attributes).

Examples

use("polmineR")

s_attributes("GERMAPARLMINI")
s_attributes("GERMAPARLMINI", "date") # dates of plenary meetings
s_attributes("GERMAPARLMINI", s_attribute = c("date", "party"))  
s_attributes(corpus("GERMAPARLMINI"))
p <- partition("GERMAPARLMINI", date = "2009-11-10")
s_attributes(p)
s_attributes(p, "speaker") # get names of speakers

# Get s-attributes occurring in a call
s_attributes(quote(grep("Merkel", speaker)), corpus = "GERMAPARLMINI")
s_attributes(quote(speaker == "Angela Merkel"), corpus = "GERMAPARLMINI")
s_attributes(quote(speaker != "Angela Merkel"), corpus = "GERMAPARLMINI")
s_attributes(
  quote(speaker == "Angela Merkel" & date == "2009-10-28"),
  corpus = "GERMAPARLMINI"
)

polmineR

Verbs and Nouns for Corpus Analysis

v0.8.5

GPL-3

Authors

Andreas Blaette [aut, cre] (<https://orcid.org/0000-0001-8970-8010>), Christoph Leonhardt [ctb]

Initial release

2020-09-22