Use of switch() in R to replace vector values

Here is the correct way to vectorize a function, e.g. switch:

# Data vector:
test <- c("He is",
          "She has",
          "He has",
          "She is")

# Vectorized SWITCH:
foo <- Vectorize(vectorize.args = "a",
                 FUN = function(a) {
                   switch(as.character(a),
                          "He is" = 1,
                          "She is" = 1,
                          "He has" = 2,
                          2)})

# Result:
foo(a = test)

  He is She has  He has  She is 
      1       2       2       1

I hope this helps.

You coud try

test_out <- sapply(seq_along(test), function(x) switch(test[x],
  "He is"=1,
  "She is"=1,
  "He has"=2,
  "She has"=2))

Or equivalently

test_out <- sapply(test, switch,
  "He is"=1,
  "She is"=1,
  "He has"=2,
  "She has"=2)