R/getSeason.R

In lhenneman/searchAQ: Import SEARCH data and detrend

#' Return season for given dates
#'
#' \code{getSeason} takes as input a vector of dates and returns the season
#'
#' @param DATES vector of dates
#' @return A vector of seasons for each date


#===============================================================#
# Return season for given dates
#================================================================#


getSeason <- function(DATES) {
  WS <- as.Date( "2012-12-21", format = "%Y-%m-%d") # Winter Solstice
  SE <- as.Date( "2012-3-20",  format = "%Y-%m-%d") # Spring Equinox
  SS <- as.Date( "2012-6-21",  format = "%Y-%m-%d") # Summer Solstice
  FE <- as.Date( "2012-9-22",  format = "%Y-%m-%d") # Fall Equinox

  # Convert dates from any year to 2012 dates
  d <- as.Date( strftime( DATES, format="2012-%m-%d"))

  ifelse ( d >= WS | d < SE, "win",
           ifelse ( d >= SE & d < SS, "spr",
                    ifelse ( d >= SS & d < FE, "sum", "fal")))
}