Projets informatiques MIMSE M2

unaccent = function(text) {
  # Supprime les accents
  text = gsub("['`^~\"]", " ", text)
  text = iconv(text, to="ASCII//TRANSLIT//IGNORE")
  text = gsub("['`^~\"]", "", text)
  return(text)
}

remove_space = function(some_txt){
  # Supprime les espaces inutiles
  some_txt = unlist(strsplit(some_txt," "))
  if (length(which(some_txt==""))!=0)
    some_txt = some_txt[-which(some_txt=="")]
  some_txt = paste(some_txt,collapse=" ")
  return(some_txt)
}

remove_apostrophe = function(some_txt){
  # Supprime les apostrophes et les remplace par des espaces
  some_txt = unlist(strsplit(some_txt,"'"))
  if (length(which(some_txt==""))!=0)
    some_txt = some_txt[-which(some_txt=="")]
  some_txt = paste(some_txt,collapse=" ")
  some_txt = unlist(strsplit(some_txt,"’"))
  if (length(which(some_txt==""))!=0)
    some_txt = some_txt[-which(some_txt=="")]
  some_txt = paste(some_txt,collapse=" ")
  return(some_txt)
}

try.error = function(x){
  # Essaie de passer le texte en minuscule, le retourne si elle y arrive, retourne NA sinon
  y = NA
  try_error = tryCatch(tolower(x), error=function(e) e)
  if (!inherits(try_error, "error"))
    y = tolower(x)
  return(y)
}

nettoyage = function(some_txt){
  # Supprime les entités RT
  some_txt = gsub("(RT|via)((?:\\b\\W*@\\w+)+)", "", some_txt)
  # Supprime les @comptes
  some_txt = gsub("@\\w+", "", some_txt)
  # Supprime les #Hashtags
  some_txt = gsub("#\\w+","",some_txt)
  # Appelle la fonction remove_apostrophe
  some_txt = unlist(lapply(some_txt,remove_apostrophe))
  # Supprime la ponctuation
  some_txt = gsub("[[:punct:]]", "", some_txt)
  # Supprime les nombres
  some_txt = gsub("[[:digit:]]", "", some_txt)
  # Supprime les liens
  some_txt = gsub("http\\w+", "", some_txt)
  # Supprime les accents (grâce à la fonction unaccent)
  some_txt = unlist(lapply(some_txt,unaccent))
  # Supprime les espaces inutiles (grâce à la fonction remove_space)
  some_txt = unlist(lapply(some_txt,remove_space))
  # Passe le texte en minuscule (grâce à la foncion try.error)
  some_txt = unlist(lapply(some_txt, try.error))
  # Supprime les NA générés par la fonction try.error
  some_txt = some_txt[!is.na(some_txt)]
  # Supprime les noms présents dans la table
  names(some_txt) = NULL
  return(some_txt)
}