R/removedips.R

In hamun001/STEF: Space-time change analysis of earth observation data for forest cover change monitoring and detection

removedips <- function(x) {
  #x <- na.approx(x, rule = 2)
  y <- as.numeric(x)
  leng <- length(x) - 2
  for(i in 1:leng)
  {
    ## moving window - check distance
    b <- i + 2
    c <- b - 1
    mida <- x[c] - x[i]
    midc <- x[c] - x[b]

    # Find 20 percent
    threshold1 <- (-1/100) * x[i]
    threshold2 <- (-1/100) * x[b]

    # check threshold
    if( mida < 0 & midc < 0 &  mida < threshold1 & midc < threshold2) {
      y[c] <- (x[b] + x[i]) / 2}
  }
  return(y)
}