R/upsample.R

In epongpipat/ppi: Psychophysiological Interaction (PPI)

#' @title upsample
#' @concept data_wrangling
#' @param data data to upsample
#' @param upsample_factor factor to upsample data
#'
#' @return
#' @export
#' @import readr
#' @examples
#' # to be added
upsample <- function(data, upsample_factor) {

  if (!is.numeric(upsample_factor) || upsample_factor <= 0) {
    stop("upsample_factor must be an integer greater than 1")
  }

  if (is.matrix(data) || is.data.frame(data)) {
    data <- as.data.frame(data)
    data <- data[, 1]
  }

  new_data <- NULL
  for (i in 1:length(data)) {
    temp_start <- data[i]

    if (i == length(data)) {
      temp_end <- data[i]
    } else {
      temp_end <- data[i+1]
    }

    temp_data <- seq(temp_start, temp_end, length.out = (upsample_factor + 1))
    temp_data <- temp_data[-length(temp_data)]
    new_data <- c(new_data, temp_data)
  }

  #data <- rep(data, each = upsample_factor)

  return(new_data)

}