用gsub替换带重音的多个字母

Question

当然我可以替换这样的特定参数:

    mydata=c("á","é","ó")
    mydata=gsub("á","a",mydata)
    mydata=gsub("é","e",mydata)
    mydata=gsub("ó","o",mydata)
    mydata

但是肯定有一种更容易的方法来完成这一切,对吧？我没有发现gsub帮助非常全面.

Answer 1

使用字符翻译功能

chartr("áéó", "aeo", mydata)

Answer 2

一个有趣的问题!我认为最简单的选择是设计一个特殊的函数,比如"multi"gsub():

mgsub <- function(pattern, replacement, x, ...) {
  if (length(pattern)!=length(replacement)) {
    stop("pattern and replacement do not have the same length.")
  }
  result <- x
  for (i in 1:length(pattern)) {
    result <- gsub(pattern[i], replacement[i], result, ...)
  }
  result
}

这给了我:

> mydata <- c("á","é","ó")
> mgsub(c("á","é","ó"), c("a","e","o"), mydata)
[1] "a" "e" "o"

Answer 3

也许这可能有用:

iconv('áéóÁÉÓçã', to="ASCII//TRANSLIT")
[1] "aeoAEOca"

Answer 4

您可以使用stringi包来替换这些字符.

> stri_trans_general(c("á","é","ó"), "latin-ascii")

[1] "a" "e" "o"

Answer 5

这与@kith非常相似,但是在函数形式中,以及最常见的diacritcs案例:

removeDiscritics <- function(string) {
  chartr(
     "ŠŽšžŸÀÁÂÃÄÅÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖÙÚÛÜÝàáâãäåçèéêëìíîïðñòóôõöùúûüýÿ"
    ,"SZszYAAAAAACEEEEIIIIDNOOOOOUUUUYaaaaaaceeeeiiiidnooooouuuuyy"
    , string
  )
}


removeDiscritics("test áéíóú")

"测试aeiou"

Answer 6

另一个mgsub实现使用Reduce

mystring = 'This is good'
myrepl = list(c('o', 'a'), c('i', 'n'))

mgsub2 <- function(myrepl, mystring){
  gsub2 <- function(l, x){
   do.call('gsub', list(x = x, pattern = l[1], replacement = l[2]))
  }
  Reduce(gsub2, myrepl, init = mystring, right = T) 
}

Answer 7

上面的一些实现(例如,Theodore Lytras的)的问题在于,如果模式是多个字符,则在一个模式是另一个模式的子串的情况下它们可能冲突.解决此问题的方法是创建对象的副本并在该副本中执行模式替换.这是在我的软件包bayesbio中实现的,可在CRAN上使用.

mgsub <- function(pattern, replacement, x, ...) {
  n = length(pattern)
  if (n != length(replacement)) {
    stop("pattern and replacement do not have the same length.")
  }
  result = x
  for (i in 1:n) {
    result[grep(pattern[i], x, ...)] = replacement[i]
  }
  return(result)
}

这是一个测试用例:

  asdf = c(4, 0, 1, 1, 3, 0, 2, 0, 1, 1)

  res = mgsub(c("0", "1", "2"), c("10", "11", "12"), asdf)