For a text or a collection of texts (in a quanteda corpus object), return a list of a keyword supplied by the user in its immediate context, identifying the source text and the word index number within the source text. (Not the line number, since the text may or may not be segmented using end-of-line delimiters.)
kwic(
x,
pattern,
window = 5,
valuetype = c("glob", "regex", "fixed"),
separator = " ",
case_insensitive = TRUE,
index = NULL,
...
)
is.kwic(x)
# S3 method for kwic
as.data.frame(x, ...)a character vector, list of character vectors, dictionary, or collocations object. See pattern for details.
the number of context words to be displayed around the keyword
the type of pattern matching: "glob" for "glob"-style
wildcard expressions; "regex" for regular expressions; or "fixed" for
exact matching. See valuetype for details.
a character to separate words in the output
logical; if TRUE, ignore case when matching a
pattern or dictionary values
an index object to specify keywords
unused
A kwic classed data.frame, with the document name
(docname) and the token index positions (from and to,
which will be the same for single-word patterns, or a sequence equal in
length to the number of elements for multi-word phrases).
pattern will be a keyword pattern or phrase, possibly multiple
patterns, that may include punctuation. If a pattern contains whitespace,
it is best to wrap it in phrase() to make this explicit. However if
pattern is a collocations (see quanteda.textstats or
dictionary object, then the collocations or multi-word dictionary keys
will automatically be considered phrases where each whitespace-separated
element matches a token in sequence.
# single token matching
toks <- tokens(data_corpus_inaugural[1:8])
kwic(toks, pattern = "secure*", valuetype = "glob", window = 3)
#> Keyword-in-context with 6 matches.
#> [1797-Adams, 478] welfare, and | secure | the blessings of
#> [1797-Adams, 1512] nations, and | secured | immortal glory with
#> [1805-Jefferson, 2367] , and shall | secure | to you the
#> [1817-Monroe, 1754] cherished. To | secure | us against these
#> [1817-Monroe, 1814] defense as to | secure | our cities and
#> [1817-Monroe, 3009] I can to | secure | economy and fidelity
#>
kwic(toks, pattern = "secur", valuetype = "regex", window = 3)
#> Keyword-in-context with 10 matches.
#> [1789-Washington, 1496] government for the | security |
#> [1797-Adams, 478] welfare, and | secure |
#> [1797-Adams, 1512] nations, and | secured |
#> [1805-Jefferson, 2367] , and shall | secure |
#> [1813-Madison, 321] seas and the | security |
#> [1817-Monroe, 1609] may form some | security |
#> [1817-Monroe, 1754] cherished. To | secure |
#> [1817-Monroe, 1814] defense as to | secure |
#> [1817-Monroe, 3009] I can to | secure |
#> [1817-Monroe, 3427] and as a | security |
#>
#> of their union
#> the blessings of
#> immortal glory with
#> to you the
#> of an important
#> against these dangers
#> us against these
#> our cities and
#> economy and fidelity
#> against foreign dangers
#>
kwic(toks, pattern = "security", valuetype = "fixed", window = 3)
#> Keyword-in-context with 4 matches.
#> [1789-Washington, 1496] government for the | security |
#> [1813-Madison, 321] seas and the | security |
#> [1817-Monroe, 1609] may form some | security |
#> [1817-Monroe, 3427] and as a | security |
#>
#> of their union
#> of an important
#> against these dangers
#> against foreign dangers
#>
# phrase matching
kwic(toks, pattern = phrase("secur* against"), window = 2)
#> Keyword-in-context with 2 matches.
#> [1817-Monroe, 1609:1610] form some | security against | these dangers
#> [1817-Monroe, 3427:3428] as a | security against | foreign dangers
#>
kwic(toks, pattern = phrase("war against"), valuetype = "regex", window = 2)
#> Keyword-in-context with 1 match.
#> [1801-Jefferson, 1268:1269] the surest | bulwarks against |
#>
#> antirepublican tendencies
#>
# use index
idx <- index(toks, phrase("secur* against"))
kwic(toks, index = idx, window = 2)
#> Keyword-in-context with 2 matches.
#> [1817-Monroe, 1609:1610] form some | security against | these dangers
#> [1817-Monroe, 3427:3428] as a | security against | foreign dangers
#>
kw <- kwic(tokens(data_corpus_inaugural[1:20]), "provident*")
is.kwic(kw)
#> [1] TRUE
is.kwic("Not a kwic")
#> [1] FALSE
is.kwic(kw[, c("pre", "post")])
#> [1] TRUE
toks <- tokens(data_corpus_inaugural[1:8])
kw <- kwic(toks, pattern = "secure*", valuetype = "glob", window = 3)
as.data.frame(kw)
#> docname from to pre keyword post pattern
#> 1 1797-Adams 478 478 welfare , and secure the blessings of secure*
#> 2 1797-Adams 1512 1512 nations , and secured immortal glory with secure*
#> 3 1805-Jefferson 2367 2367 , and shall secure to you the secure*
#> 4 1817-Monroe 1754 1754 cherished . To secure us against these secure*
#> 5 1817-Monroe 1814 1814 defense as to secure our cities and secure*
#> 6 1817-Monroe 3009 3009 I can to secure economy and fidelity secure*