R/tableChange.R

In EGRET: Exploration and Graphics for RivEr Trends

#' Create a table of the changes in flow-normalized values between various points in time in the record
#'
#' These tables describe trends in flow-normalized concentration and in flow-normalized flux. 
#' They are described as changes in real units or in percent and as slopes in real units per year or in percent per year.
#' They are computed over pairs of time points.  These time points can be user-defined or
#' they can be set by the program to be the final year of the record and a set of years that are multiples of 5 years prior to that.
#' tableChangeSingle is a version of the same code that will produce output only for flow-normalized concentration or flow-normalized flux, but not both
#'
#' @param eList named list with at least the Daily and INFO dataframes
#' @param fluxUnit object of fluxUnit class. \code{\link{printFluxUnitCheatSheet}}, or numeric represented the short code, or character representing the descriptive name.
#' @param yearPoints numeric vector listing the years for which the change or slope computations are made, they need to be in chronological order.  For example yearPoints=c(1975,1985,1995,2005), default is NA (which allows the program to set yearPoints automatically)
#' @keywords water-quality statistics
#' @export
#' @rdname tableChange
#' @examples
#' eList <- Choptank_eList
#' # Water Year:
#' \donttest{
#' tableChange(eList, fluxUnit = 8, yearPoints = c(1980, 1995, 2011))
#' tableChange(eList, fluxUnit = 5) 
#' # Winter:
#' eList <- setPA(eList, paStart = 12, paLong = 3)
#' tableChange(eList, fluxUnit = 8, yearPoints = c(1980, 1995, 2011))
#' 
#' # Water Year:
#' eList <- setPA(eList, paStart = 10, paLong = 12)
#' #This returns concentration ASCII table in the console:
#' tableChangeSingle(eList, fluxUnit = 8, yearPoints = c(1980, 1995, 2011), flux = FALSE)
#' #Returns a data frame:
#' change <- tableChangeSingle(eList, fluxUnit = 8, yearPoints=c(1980, 1995, 2011), flux = FALSE) 
#' #This returns flux values as a data frame:
#' df <- tableChangeSingle(eList, fluxUnit = 8, yearPoints=c(1980, 1995, 2011), flux = TRUE)  
#' # Winter Concentration only:
#' eList <- setPA(eList, paStart = 12, paLong = 3)
#' df.winter <- tableChangeSingle(eList, fluxUnit = 8, yearPoints=c(1980, 1995, 2011), flux = FALSE)
#' 
#' }
tableChange <- function(eList, fluxUnit = 9, yearPoints = NA) {
  
  localINFO <- getInfo(eList)
  localDaily <- getDaily(eList)
  
  if(!all(c("FNFlux", "FNConc") %in% names(localDaily))){
    stop("Must run modelEstimation on eList first.")
  }
  
  if(all(c("paStart","paLong") %in% names(localINFO))){
    paLong <- localINFO$paLong
    paStart <- localINFO$paStart  
  } else {
    paLong <- 12
    paStart <- 10
  }
  
  possibleGoodUnits <- c("mg/l","mg/l as N", "mg/l as NO2", 
                         "mg/l as NO3","mg/l as P","mg/l as PO3","mg/l as PO4","mg/l as CaCO3",
                         "mg/l as Na","mg/l as H","mg/l as S","mg/l NH4" )
  
  allCaps <- toupper(possibleGoodUnits)
  localUnits <- toupper(localINFO$param.units)
  
  if(!(localUnits %in% allCaps)){
    warning("Expected concentration units are mg/l, \nThe INFO dataframe indicates:",localINFO$param.units,
            "\nFlux calculations will be wrong if units are not consistent")
  }
  
  localAnnualResults <- setupYears(paStart = paStart,
                                   paLong = paLong,
                                   localDaily = localDaily)
  localAnnualResults <- localAnnualResults[rowSums(is.na(localAnnualResults[,c("Conc","Flux","FNConc","FNFlux")])) != 4,]
  
  ################################################################################
  # I plan to make this a method, so we don't have to repeat it in every funciton:
  if (is.numeric(fluxUnit)){
    fluxUnit <- fluxConst[shortCode=fluxUnit][[1]]    
  } else if (is.character(fluxUnit)){
    fluxUnit <- fluxConst[fluxUnit][[1]]
  }
  ################################################################################ 
  period <- paLong/12
  
  firstYear <- trunc(localAnnualResults$DecYear[1] + period/2)
  numYears <- length(localAnnualResults$DecYear)

  lastYear <- trunc(localAnnualResults$DecYear[numYears] + period/2)
  defaultYearPoints <- seq(lastYear,firstYear,-5)
  numPoints <- length(defaultYearPoints)
  defaultYearPoints[1:numPoints] <- defaultYearPoints[numPoints:1]
  yearPoints <- if(is.na(yearPoints[1])) defaultYearPoints else yearPoints
  numPoints <- length(yearPoints)
  # these last three lines check to make sure that the yearPoints are in the range of the data	
  yearPoints <- if(yearPoints[numPoints] > lastYear) defaultYearPoints else yearPoints
  yearPoints <- if(yearPoints[1] < firstYear) defaultYearPoints else yearPoints
  numPoints <- length(yearPoints)
  fluxFactor <- fluxUnit@unitFactor
  fName <- fluxUnit@shortName
  cat("\n  ", localINFO$shortName, "\n  ", localINFO$paramShortName)
  periodName <- setSeasonLabel(localAnnualResults = localAnnualResults)
  hasFlex <- c("segmentInfo") %in% names(attributes(eList$INFO))
  
  if(hasFlex){
    periodName <- paste(periodName,"*")
  }
  
  cat("\n  ",periodName,"\n")
  header1 <- "\n           Concentration trends\n   time span       change     slope    change     slope\n                     mg/L   mg/L/yr        %       %/yr"
  header2 <- "\n\n\n                 Flux Trends\n   time span          change        slope       change        slope"
  blankHolder <- "      ---"
  results <- rep(NA,4)
  indexPoints <- yearPoints-firstYear+1
  numPointsMinusOne <- numPoints-1
  write(header1,file="")
  
  for(iFirst in 1:numPointsMinusOne) {
    xFirst <- indexPoints[iFirst]
    yFirst <- localAnnualResults$FNConc[indexPoints[iFirst]]
    iFirstPlusOne <- iFirst+1
    for(iLast in iFirstPlusOne:numPoints) {
      xLast <- indexPoints[iLast]
      yLast <- localAnnualResults$FNConc[indexPoints[iLast]]
      xDif <- xLast - xFirst
      yDif <- yLast - yFirst
      results[1] <- if(is.na(yDif)) blankHolder else format(yDif,digits=2,width=9)
      results[2] <- if(is.na(yDif)) blankHolder else format(yDif/xDif,digits=2,width=9)
      results[3] <- if(is.na(yDif)) blankHolder else format(100*yDif/yFirst,digits=2,width=9)
      results[4] <- if(is.na(yDif)) blankHolder else format(100*yDif/yFirst/xDif,digits=2,width=9)
      cat("\n",yearPoints[iFirst]," to ",yearPoints[iLast],results)
    }}
  write(header2,file="")
  cat("              ",fName,fName,"/yr      %         %/yr")
  for(iFirst in 1:numPointsMinusOne) {
    xFirst <- indexPoints[iFirst]
    yFirst <- localAnnualResults$FNFlux[indexPoints[iFirst]]*fluxFactor
    iFirstPlusOne <- iFirst+1
    for(iLast in iFirstPlusOne:numPoints) {
      xLast <- indexPoints[iLast]
      yLast <- localAnnualResults$FNFlux[indexPoints[iLast]]*fluxFactor
      xDif <- xLast - xFirst
      yDif <- yLast - yFirst
      results[1] <- if(is.na(yDif)) blankHolder else format(yDif,digits=2,width=12)
      results[2] <- if(is.na(yDif)) blankHolder else format(yDif/xDif,digits=2,width=12)
      results[3] <- if(is.na(yDif)) blankHolder else format(100*yDif/yFirst,digits=2,width=12)
      results[4] <- if(is.na(yDif)) blankHolder else format(100*yDif/yFirst/xDif,digits=2,width=12)
      cat("\n", yearPoints[iFirst], " to ", yearPoints[iLast],results)
    }
  }
}