R: Convert the case of the features of a dfm and combine

dfm_tolower {quanteda} | R Documentation

## 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)

[Package quanteda version 3.1.0 Index]