Convert the case of character objects

Source: R/casechange-functions.R

char_tolower and char_toupper are replacements for base::tolower() and base::tolower() based on the stringi package. The stringi functions for case conversion are superior to the base functions because they correctly handle case conversion for Unicode. In addition, the *_tolower() functions provide an option for preserving acronyms.

char_tolower(x, keep_acronyms = FALSE)

char_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)

Examples

txt1 <- c(txt1 = "b A A", txt2 = "C C a b B")
char_tolower(txt1)
#>        txt1        txt2 
#>     "b a a" "c c a b b" 
char_toupper(txt1)
#>        txt1        txt2 
#>     "B A A" "C C A B B" 

# with acronym preservation
txt2 <- c(text1 = "England and France are members of NATO and UNESCO",
          text2 = "NASA sent a rocket into space.")
char_tolower(txt2)
#>                                               text1 
#> "england and france are members of nato and unesco" 
#>                                               text2 
#>                    "nasa sent a rocket into space." 
char_tolower(txt2, keep_acronyms = TRUE)
#>                                               text1 
#> "england and france are members of NATO and UNESCO" 
#>                                               text2 
#>                    "NASA sent a rocket into space." 
char_toupper(txt2)
#>                                               text1 
#> "ENGLAND AND FRANCE ARE MEMBERS OF NATO AND UNESCO" 
#>                                               text2 
#>                    "NASA SENT A ROCKET INTO SPACE."