R/get_date_range.R

In WorldHealthOrganization/godataR: Connecting R with the Go.Data Application

#' Get minimum and maximum date for a vector of dates
#'
#' @author Amy Mikhail, \email{amy.mikhail@@gmail.com}
#'
#' @description
#' This function will attempt to auto-detect the date format using lubridate,
#' then determine the minimum and maximum for the submitted vector of dates.
#' It is intended as a helper function for selecting date ranges and adding
#' them to queries.
#'
#' @md
#'
#' @param dates character vector of dates to extract the date range from
#'
#' @return
#' Returns a list object with two values (minimum and maximum date)
#'
#' @import lubridate
#'
#' @examples
#' # Create a character vector of dates:
#' x <- c("2022-07-15", "2021-08-09", NA, "2022-08-03")
#'
#' # Get date range:
#' daterange <- get_date_range(dates = x)
#'
#' # View the result:
#' daterange
#' @export
get_date_range <- function(dates) {

  # Check if the input variable is already in date format:
  if (any(class(dates) %in% c("Date", "POSIXt"))) {

    # If yes, no need to format:
    dates2range <- dates

  } else {

    # If no, convert to date format with lubridate:
    dates2range <- lubridate::parse_date_time(
      x = dates,
      orders = c("ymd", "dmy", "mdy")
    )
  }

  # Get the minimum date:
  mindate <- min(dates2range, na.rm = TRUE)

  # Get the maximum date:
  maxdate <- max(dates2range, na.rm = TRUE)

  # Compile results:
  daterange <- list(mindate = mindate, maxdate = maxdate)

  # Return the results:
  return(daterange)
}