R/fixDateline.R

In EricArcher/PAMsbuoy: Manipulation and filtering for PAM (Passive Acoustic Monitoring) data collected from sonobuoys

#' @name fixDateline
#' @title Fix Longitude Data Across the Dateline
#' @description Returns a dataframe identical to the input after checking
#'    if the \code{Longitude} column crosses the dateline. If it does,
#'    check whether the center is positive or negative and set all values
#'    to the same sign.
#'
#' @param data data frame with a \code{Longitude} column to adjust for
#'    cross-dateline plotting
#'
#' @author Taiki Sakai \email{taiki.sakai@@noaa.gov}
#'
fixDateline <- function(data) {
  boundLong <- range(data$Longitude)
  if(boundLong[2]-boundLong[1] > 180) {
    if(sum(boundLong) < 0) {
      data$Longitude <- (data$Longitude %% 360)
    } else {
      data$Longitude <- (data$Longitude %% 360) - 360
    }
  }
  data
}