vectorizing "if" in R

Question

I have an array of probability over a classification

post <- c(0.73,0.69,0.44,0.55,0.67,0.47,0.08,0.15,0.45,0.35)

and I want to retrieve the predicted class. right now I use

predicted <- function(post) { 
               function(threshold) {plyr::aaply(post, 1, 
                   function(x) {if(x >= threshold) '+' else '-'})}}

but that seems like something R would have a syntax for.

Is there some indexing expression that would be more direct ?

Answer 1

pred <- c("-", "+")[1+(post > 0.5)]