Removes sentences from a corpus or a character vector shorter than a specified length.

corpus_trim(x, what = c("sentences", "paragraphs", "documents"),
  min_ntoken = 1, max_ntoken = NULL, exclude_pattern = NULL)

char_trim(x, what = c("sentences", "paragraphs", "documents"),
  min_ntoken = 1, max_ntoken = NULL, exclude_pattern = NULL)

Arguments

x

corpus or character object whose sentences will be selected.

what

units of triming, "sentences" or "paragraphs", or "documents"

min_ntoken, max_ntoken

minimum and maximum lengths in word tokens (excluding punctuation)

exclude_pattern

a stringi regular expression whose match (at the sentence level) will be used to exclude sentences

Value

a corpus or character vector equal in length to the input. If the input was a corpus, then the all docvars and metadata are preserved. For documents whose sentences have been removed entirely, a null string ("") will be returned.

Examples

txt <- c("PAGE 1. This is a single sentence. Short sentence. Three word sentence.", "PAGE 2. Very short! Shorter.", "Very long sentence, with multiple parts, separated by commas. PAGE 3.") mycorp <- corpus(txt, docvars = data.frame(serial = 1:3)) texts(mycorp)
#> text1 #> "PAGE 1. This is a single sentence. Short sentence. Three word sentence." #> text2 #> "PAGE 2. Very short! Shorter." #> text3 #> "Very long sentence, with multiple parts, separated by commas. PAGE 3."
# exclude sentences shorter than 3 tokens texts(corpus_trim(mycorp, min_ntoken = 3))
#> text1 #> "This is a single sentence. Three word sentence." #> text3 #> "Very long sentence, with multiple parts, separated by commas."
# exclude sentences that start with "PAGE <digit(s)>" texts(corpus_trim(mycorp, exclude_pattern = "^PAGE \\d+"))
#> text1 #> "This is a single sentence. Short sentence. Three word sentence." #> text2 #> "Very short! Shorter." #> text3 #> "Very long sentence, with multiple parts, separated by commas."
# trimming character objects char_trim(txt, "sentences", min_ntoken = 3)
#> text1 #> "This is a single sentence. Three word sentence." #> text3 #> "Very long sentence, with multiple parts, separated by commas."
char_trim(txt, "sentences", exclude_pattern = "sentence\\.")
#> text1 #> "PAGE 1." #> text2 #> "PAGE 2. Very short! Shorter." #> text3 #> "Very long sentence, with multiple parts, separated by commas. PAGE 3."