data extraction functions.r

# Determines if the vector does not having missing data over the range specified
contains_values <- function(start, end, coll) {
  temp <- coll[start:end]
  return(length(temp[!is.na(temp)]) == (end - start + 1))
}

# Determines if the data entry at this index is viable for consideration
is_good_index <- function(k, idx, coll) {
  return(contains_values(idx - k, idx, coll))
}

# Finds all of the good indicies in the vector
find_good_indicies <- function(k, coll) {
  idxs <- k : (length(coll))
  vals <- sapply(idxs, function(idx) {
    return(is_good_index(k, idx, coll))
  })
  return(idxs[vals])
}