R/swmm.R

In dleutnant/tsconvert: Read and Convert Time Series Data

#' Reads the .csv structured time series data output generated by the stormwater 
#' management model 'SWMM' and creates an xts-object. For reading the binary output 
#' please check the swmmr-package (https://github.com/dleutnant/swmmr).
#'
#' @title Read time series data from SWMM
#' @param file The file to be read
#' @param header s. read.table
#' @param sep s. read.table
#' @param dec s. read.table
#' @param skip s. read.table
#' @param stringsAsFactors s. read.table
#' @param fileEncoding s. read.table
#' @param format s. read.table
#' @param tz Sets the time zone.
#' @param verbose logical. Provide additional details?
#' @return An xts-object.
#' @rdname read_swmm_dat
#' @export 
#' @seealso \code{\link[xts]{xts}}.
read_swmm_dat  <-  function(file, 
                            header = FALSE,
                            sep = "",
                            dec = ".",
                            skip = 1,
                            stringsAsFactors = F,
                            fileEncoding = "UTF-8",
                            format = "%m/%d/%Y %H:%M",
                            tz = "GMT",
                            verbose = FALSE) {
  if (verbose) print(file)
  
  # get attributes of first lines 
  ## TODO
  
  data <- utils::read.table(file = file,
                            header = header, 
                            sep = sep,
                            dec = dec,
                            skip = skip, 
                            stringsAsFactors = stringsAsFactors,
                            fileEncoding = fileEncoding)
  
  coredata  <- as.numeric(data$V3)
  
  timedata <- paste(data$V1, data$V2)
  
  timedata <- as.POSIXct(timedata, 
                         format = format,
                         tz = tz)
  
  swmmdata <- xts::xts(coredata,timedata)

  invisible(swmmdata)
  
}

#' Writes a xts-object to .dat structured time series data format usually 
#' interpreted by the stormwater management model 'SWMM'.
#'
#' @title Write xts-objects to .dat file format
#' @param xts The xts object to be written.
#' @param file A character string naming the file to write to.
#' @param is_rainfall logical. TRUE shifts coredata values with specified 
#' seconds (default is -60)
#' @param seconds The seconds to shift to.
#' @param is_caldata logical. Modifies the header if .dat output.
#' @param digits Number of digits to write.
#' @rdname write_swmm_dat
#' @export
#' @seealso \code{\link{xts}}, \code{\link{write.table}}.
write_swmm_dat <- function(xts, file, 
                           is_rainfall = FALSE,
                           seconds = -60, 
                           is_caldata = FALSE, 
                           digits = 6) {
  
  mname <- attr(xts,which = "ZRID")
  if (identical(mname, character(0))) mname <- "NoName"
  mpara <- attr(xts,which = "Parameter")
  if (identical(mpara, character(0))) mpara <- "NoParameter"
  munit <- attr(xts,which = "Einheit")
  if (identical(munit, character(0))) munit <- "NoUnit"
  
  xts <- xts[zoo::coredata(xts) != 0]
  
  # respect blockanfang
  if (is_rainfall) {
    xts <- .shift.index(xts, seconds = seconds)
  }
  
  if (is_caldata) {
    colstring <- c("index", "data") 
  } else {
    colstring <- c(";",paste("Name:",mname,";Messgroesse:", mpara, ";Einheit:",munit) )
  }

  utils::write.table(data.frame(format.POSIXct(zoo::index(xts),
                                               format = "%m/%d/%Y %H:%M"),
                                round(x = zoo::coredata(xts), digits = digits)),
                     file = file, 
                     sep = "  ",
                     quote = FALSE,
                     row.names = FALSE,
                     col.names = colstring)
  
}

# write.SWMM.calData <- function(xts, file){
#   
#   mname <- attr(xts,which="ZRID")
#   if (identical(mname, character(0))) mname <- "NoName"
#   mpara <- attr(xts,which="Parameter")
#   if (identical(mpara, character(0))) mpara <- "NoParameter"
#   munit <- attr(xts,which="Einheit")
#   if (identical(munit, character(0))) munit <- "NoUnit"
#   
#   xts <- xts[coredata(xts)!=0]
#   
#   write.table(data.frame(format.POSIXct(index(xts),format="%m/%d/%y %H:%M"),
#                          coredata(xts)),
#               file=file, 
#               sep=",",
#               quote=FALSE,
#               row.names=FALSE,
#               col.names=c("index", "data") )
# }