R/common_helper.R

In bnaras/pip: Platelet Inventory Prediction

#' Return the positive part of a value
#' @param x the vector
#' @return the maximum of x and 0
#' @export
pos <- function(x) pmax(x, 0)

## expandWeek <- function(days){
##   weeks0 = days%%7
##   weeks = matrix(0, ncol = 7, nrow = length(weeks0))
##   for(i in 0:6){
##     if(i != 0){
##       weeks[weeks0 == i, i] = 1
##     } else {
##       weeks[weeks0 == i, 7] = 1
##     }
##   }
##   weeks
## }
## ma <- function(z, n=5) {
##   res <- numeric(length(z)-n)
##   for(i in 1:(length(res))){
##     res[i] <- mean(z[i:(i+n-1)])}
##   return(res)
## }

# moving average of past n days, padding the front with NAs
## mamiss <- function(z, n=7){
##   c(rep(NA, n), ma(z, n))
## }

## Does cross validation

create_folds <- function(n, nfold){
    foldid  <- integer(n)
    fold_len <- floor( (n + 0.1) / nfold )
    for(i in seq.int(0, nfold - 1L)){
        if(i < nfold - 1L){
            foldid[(i*fold_len):((i+1)*fold_len)] = i+1
        }else{
            foldid[(i*fold_len):n] = i+1
        }
    }
  foldid
}