R/argmin.R

In maxwestphal/DTAmc: Diagnostic Test Accuracy studies with multiple comparisons

argmin <- function(x, rdm=FALSE){
  am <- which(x == min(x))
  # deterministic output, if required, otherwise randomize in case of ties
  if(!rdm){ 
    return(min(am))
  }
  if(length(am) == 1){
    return(am)
  }else{
    return(sample(am, 1))
  }
}

pargmin <- function(..., args=list(), rdm=FALSE){
  args <- c(list(...), args)
  stopifnot(is.list(args))
  stopifnot(do.call(all.equal, lapply(args, length)))
  apply(as.data.frame(args), 1, argmin, rdm=rdm)
}

argmax <- function(x, rdm=FALSE) {
  argmin(-x, rdm)
}

pargmax <- function(..., args=list(), rdm=FALSE){
  args <- c(list(...), args)
  args <- lapply(args, function(x){-x})
  pargmin(args=args, rdm=rdm)
}