R/fBIST.R

In enesn/rBIST: R/BIST

#' Fetch XU100 Index
#'
#' Fetches XU100 index data from historical data service
#'
#' @param startDate A character object "MM-DD-YYYY".When argument is NULL function fetches all dates.
#' @param endDate A character object "MM-DD-YYYY". When stardDate is NULL, endDate should be NULL.
#'
#' @export
fBIST <- function(startDate=NULL,endDate=NULL) {
  ## setup local time according os before set xts.
  if (Sys.info()[['sysname']]== "Windows") {

    Sys.setlocale("LC_TIME", "English")
  }
  else
     Sys.setlocale("LC_TIME", "en_US.UTF-8")  ## to set up xts.

  #################################################

  if(is.null(startDate)) {

    src <- paste0("https://www.google.com/finance/historical?q=INDEXIST%3AXU100&output=csv")
    if(!is.null(endDate)) {

      stop(paste0("When starDate argument is null, endDate have to null."))
    }
  }

  else {
    src <-paste0("https://www.google.com/finance/historical?q=INDEXIST%3AXU100
                   &startdate=",startDate,"&enddate=",endDate,"&output=csv")
  }

  delta <- read.csv(src, sep=",")
  delta <- delta[,-6]
  bar <- strptime(delta[,1], format = "%d-%b-%y","GMT")        # set time to xts
  delta[[1]] <- bar
  delta<- xts(delta[,-1], order.by=delta[,1])                  # convert data.frame to xts.
  delta

}