R/calcRelativeCoords.r

In kleebaum/geoelectrics: 3D-Visualization of Geoelectric Resistivity Measurement Profiles

#' Calculate Relative Coordinates
#'
#' Calculates relative coordinates (unity: meters) from GPS coordinates
#' (either given in UTM or Gauss Krueger).
#' This method is used when a profile set of many profiles is instantiated.
#'
#' @param coords exact coordinates of a single Profile.
#' @param minLat starting point (latititude).
#' @param minLon starting point (longitude).
#' @return data frame that contains the relative coordinates (latitude and longitude).
#' @export
#' @seealso \code{\link{ProfileSet-class}}, \code{\link{GpsCoordinates-class}}
calcRelativeCoords <- function(coords, minLat, minLon) {
  # latitude and longitude
  if (max(coords@exact$lat) < 180) {
    # Gauss Krueger
    relativeCoords <- data.frame(
      lat = (coords@exact$lat - minLat) * 111000,
      lon = (coords@exact$lon - minLon) * 72000
    )
  }
  else {
    # UTM
    relativeCoords <- data.frame(
      lat = (coords@exact$lat - minLat),
      lon = (coords@exact$lon - minLon)
    )
  }
  return(relativeCoords)
}