polmineR (version 0.8.9)

cqp: Tools for CQP queries.

Description

Test whether a character string is a CQP query, or turn a character vector into CQP queries.

Usage

is.cqp(query)
check_cqp_query(query, warn = TRUE)
as.cqp(
  query,
  normalise.case = FALSE,
  collapse = FALSE,
  check = TRUE,
  warn = TRUE
)

Value

is.cqp returns a logical value, as.cqp a character vector, check_cqp_query a logical value that is TRUE if all queries are valid, or FALSE if not.

Arguments

query

A character vector with at least one CQP query.

warn

A (length-one) logical value, whether to issue a warning if a query may be buggy.

normalise.case

A logical value, if TRUE, a flag will be added to the query/queries to omit matching case.

collapse

A logical value, whether to collapse the queries into one.

check

A logical value whether to run check_cqp_query() on queries.

Details

The is.cqp() function guesses whether query is a CQP query and returns the respective logical value (TRUE/FALSE).

The as.cqp() function takes a character vector as input and converts it to a CQP query by putting the individual strings in quotation marks.

The check_cqp_query-function will check that opening quotation marks are matched by closing quotation marks, to prevent crashes of CQP and the R session.

References

CQP Query Language Tutorial (https://cwb.sourceforge.io/files/CQP_Tutorial.pdf)

Examples

is.cqp("migration") # will return FALSE
is.cqp('"migration"') # will return TRUE
is.cqp('[pos = "ADJA"] "migration"') # will return TRUE

as.cqp("migration")
as.cqp(c("migration", "diversity"))
as.cqp(c("migration", "diversity"), collapse = TRUE)
as.cqp("migration", normalise.case = TRUE)

check_cqp_query('"Integration.*"') # TRUE, the query is ok
check_cqp_query('"Integration.*') # FALSE, closing quotation mark is missing
check_cqp_query("'Integration.*") # FALSE, closing quotation mark is missing
check_cqp_query(c("'Integration.*", '"Integration.*')) # FALSE too