R/row_locations.R

In khufkens/junglerhythms: Process and screen raw Zooniverse's Jungle Rhythms data

#' calculate the approximate location of the rows
#'
#' Use the corners of the yearly section (provided as a vector)
#' in order: bottom_left, top_left, bottom_middle,top_middle,
#' bottom_right, top_right
#'
#' @param coord coordinates
#' @export
#' @return location and length of row

row_locations = function(coord) {

  # start of the year
  d_left_start = sqrt((coord[1] - coord[3]) ^ 2 + (coord[2] - coord[4]) ^ 2)
  d_left_start = d_left_start / 5
  d_right_start = sqrt((coord[5] - coord[7]) ^ 2 + (coord[6] - coord[8]) ^ 2)
  d_right_start = d_right_start / 5

  left_start = matrix(unlist(lapply(1:4 * d_left_start,
                                    function(x){
    intersect_line_circle(coord[1:2], coord[3:4], x)})),
    4, 2, byrow = T)

  right_start = matrix(unlist(lapply(1:4 * d_right_start, function(x){
    intersect_line_circle(coord[5:6], coord[7:8], x)})),
    4, 2, byrow = T)
  d_start = mean(c(d_left_start, d_right_start))

  # end of the year
  d_left_end = sqrt((coord[5] - coord[7]) ^ 2 + (coord[6] - coord[8]) ^ 2)
  d_left_end = d_left_end / 5
  d_right_end = sqrt((coord[9] - coord[11]) ^ 2 + (coord[10] - coord[12]) ^ 2)
  d_right_end = d_right_end / 5
  left_end = right_start
  right_end = matrix(unlist(lapply(1:4 * d_right_end, function(x)
    intersect_line_circle(coord[9:10], coord[11:12], x))), 4, 2, byrow = T)
  d_end = mean(c(d_left_end, d_right_end))

  # bind
  t_start = cbind(left_start, right_start)
  t_end = cbind(left_end, right_end)

  # output as nested list
  return(list(t_start, t_end, d_start, d_end))

}