quanteda: dfm_tolower – R documentation

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dfm_tolower

Convert the case of the features of a dfm and combine

Description

dfm_tolower() and dfm_toupper() convert the features of the dfm or fcm to lower and upper case, respectively, and then recombine the counts.

Usage

dfm_tolower(x, keep_acronyms = FALSE)

dfm_toupper(x)

fcm_tolower(x, keep_acronyms = FALSE)

fcm_toupper(x)

Arguments

`x`	the input object whose character/tokens/feature elements will be case-converted
`keep_acronyms`	logical; if `TRUE`, do not lowercase any all-uppercase words (applies only to `*_tolower()` functions)

Details

fcm_tolower() and fcm_toupper() convert both dimensions of the fcm to lower and upper case, respectively, and then recombine the counts. This works only on fcm objects created with context = "document".

Examples

# for a document-feature matrix
dfmat <- dfm(tokens(c("b A A", "C C a b B")), tolower = FALSE)
dfmat
dfm_tolower(dfmat)
dfm_toupper(dfmat)

# for a feature co-occurrence matrix
fcmat <- fcm(tokens(c("b A A d", "C C a b B e")),
             context = "document")
fcmat
fcm_tolower(fcmat)
fcm_toupper(fcmat)

quanteda

Quantitative Analysis of Textual Data

v3.0.0

GPL-3

Authors

Kenneth Benoit [cre, aut, cph] (<https://orcid.org/0000-0002-0797-564X>), Kohei Watanabe [aut] (<https://orcid.org/0000-0001-6519-5265>), Haiyan Wang [aut] (<https://orcid.org/0000-0003-4992-4311>), Paul Nulty [aut] (<https://orcid.org/0000-0002-7214-4666>), Adam Obeng [aut] (<https://orcid.org/0000-0002-2906-4775>), Stefan Müller [aut] (<https://orcid.org/0000-0002-6315-4125>), Akitaka Matsuo [aut] (<https://orcid.org/0000-0002-3323-6330>), William Lowe [aut] (<https://orcid.org/0000-0002-1549-6163>), Christian Müller [ctb], European Research Council [fnd] (ERC-2011-StG 283794-QUANTESS)

Initial release