R/lonsex2dec.R

In vmsbase/R-vmsbase: GUI Tools to Process, Analyze and Plot Fisheries Data

#' Sexagesimal to Decimal Longitude conversion function
#'
#' \code{lonsex2dec} converts sexagesimal longitude data to decimal longitude values.
#'
#' @param degree    The value in degrees of the longitude.
#' @param minute    The value in minutes of the longitude.
#' @param second    The value in seconds of the longitude.
#' @param direction   The direction, as "E" or "W", of the longitude.
#'
#' @return The function returns the longitude value converted in the decimal numeral system
#'
#' @usage lonsex2dec(degree, minute, second, direction)
#'
#' @examples
#' lonsex2dec(degree = 10, minute = 10, second = 10, direction = "W")
#' 

# LON_SEX2DEC
# Converts longitude from sexagesimal to decimal numeral system.

lonsex2dec <- function(degree, minute, second, direction) {
  if (direction == "E") {
    declon <- degree + (minute / 60) + (second / 3600)
  } else {
    declon <- -(degree + (minute / 60) + (second / 3600))
  }
  return(declon)
}