R/utils.R

In sillasgonzaga/lexiconPT: Lexicons for Portuguese Text Analysis

#' get_word_sentiment
#'
#' Lookup word or term in datasets available on lexiconPT
#'
#' @param word character.
#'
#' @return A list of all datasets available on lexiconPT filtered by the inputed word.
#' @examples{
#'   get_word_sentiment("cantar")
#'   \dontshow{
#'   get_word_sentiment("facil")
#'   }
#'  }
#' @export
get_word_sentiment <- function(word,
                               dictionary = c("all", "oplexicon_v2", "oplexicon_v3",
                                              "sentilex")){

  notAvailable <- function(df) {
    if(nrow(df) == 0) return("Word not present in dataset") else df
  }
  x1 <- notAvailable(oplexicon_v2.1[oplexicon_v2.1[["term"]] == word, ])
  x2 <- notAvailable(oplexicon_v3.0[oplexicon_v3.0[["term"]] == word, ])
  x3 <- notAvailable(sentiLex_lem_PT02[sentiLex_lem_PT02[["term"]] == word, ])

  dict <- match.arg(dictionary, choices = c("all", "oplexicon_v2", "oplexicon_v3", "sentilex"))
  if(dict == "all"){
    return(list(
      oplexicon_v2.1 = x1,
      oplexicon_v3.0 = x2,
      sentilex = x3
    ))
  } else if(dict == "oplexicon_v2"){
    return(x1)
  } else if(dict == "oplexicon_v3"){
    return(x2)
  } else {
    return(x3)
  }

}

#' @export
get_polarity <- function(word){
  x <- get_word_sentiment(word, dictionary = "oplexicon_v3")

  if(length(x) == 1){
    p <- 0
    return(p)
  } else{
    p <- x$polarity
    return(p)
  }
}