load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"

load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_csm.ncl"

procedure pminmax(data:numeric,name:string)

begin

  print ("min/max " + name + " = " + min(data) + "/" + max(data))

  if(isatt(data,"units")) then

    print (name + " units = " + data@units)

  end if

end

;

; Main code.

;

begin

  data_types    = (/ "Obs",        "Model"       /)

  data_names    = (/ "data.81.nc", "i01.03cn_1545-1569_ANN_climo.nc" /)

; data_names    = (/ "data.81.nc", "i01.04casa_1605-1629_ANN_climo.nc" /)

  filevar_names = (/ (/"PREC_ANN","TNPP_C"/), (/"RAIN","NPP"/) /)

  ndata_types   = dimsizes(data_types)

  data_file_obs = addfile(data_names(0),"r")    ; Open obs file

  data_file_mod = addfile(data_names(1),"r")    ; Open model file

;

; Read four variables from files.

;

  PREC_ANN = tofloat(data_file_obs->PREC_ANN)

  TNPP_C   = data_file_obs->TNPP_C

  RAIN     = data_file_mod->RAIN

  NPP    = data_file_mod->NPP

;

; Units for these four variables are:

;

; PREC_ANN : mm/year

; TNPP_C   : g C/m^2/year

; RAIN     : mm/s

; NPP    : g C/m^2/s

;

; We want to convert these to "m/year" and "g C/m^2/year".

;

  nsec_per_year = 60*60*24*365                  ; # seconds per year

; Do the necessary conversions.

  PREC_ANN = PREC_ANN / 1000.

  RAIN     = (RAIN / 1000.) * nsec_per_year

  NPP    = NPP * nsec_per_year

; Redo the units.

  PREC_ANN@units = "m/yr"

  RAIN@units     = "m/yr"

  NPP@units    = "gC/m^2/yr"

  TNPP_C@units   = "gC/m^2/yr"

  pminmax(PREC_ANN,"PREC_ANN")

  pminmax(TNPP_C,"TNPP_C")

  pminmax(RAIN,"RAIN")

  pminmax(NPP,"NPP")

  RAIN_1D     = ndtooned(RAIN)

  NPP_1D    = ndtooned(NPP)

  PREC_ANN_1D = ndtooned(PREC_ANN)

  TNPP_C_1D   = ndtooned(TNPP_C)

;

; Calculate some "nice" bins for binning the data in equally spaced

; ranges.

;

  nbins       = 15     ; Number of bins to use.

  nicevals    = nice_mnmxintvl(min(RAIN_1D),max(RAIN_1D),nbins,True)

  nvals       = floattoint((nicevals(1) - nicevals(0))/nicevals(2) + 1)

  range       = fspan(nicevals(0),nicevals(1),nvals)

;

; Use this range information to grab all the values in a

; particular range, and then take an average.

;

  nr      = dimsizes(range)

  nx      = nr-1

  xvalues     = new((/2,nx/),typeof(RAIN_1D))

  xvalues(0,:) = range(0:nr-2) + (range(1:)-range(0:nr-2))/2.

  dx           = xvalues(0,1) - xvalues(0,0)       ; range width

  dx4          = dx/4                              ; 1/4 of the range

  xvalues(1,:) = xvalues(0,:) - dx/5.

  yvalues      = new((/2,nx/),typeof(RAIN_1D))

  mn_yvalues   = new((/2,nx/),typeof(RAIN_1D))

  mx_yvalues   = new((/2,nx/),typeof(RAIN_1D))

  do nd=0,1

;

; See if we are doing model or observational data.

;

    if(nd.eq.0) then

      data     = PREC_ANN_1D

      npp_data = TNPP_C_1D

    else

      data     = RAIN_1D

      npp_data = NPP_1D

    end if

;

; Loop through each range and check for values.

;

    do i=0,nr-2

      if (i.ne.(nr-2)) then

        print("")

        print("In range ["+range(i)+","+range(i+1)+")")

        idx = ind((range(i).le.data).and.(data.lt.range(i+1)))

      else

        print("")

        print("In range ["+range(i)+",)")

        idx = ind(range(i).le.data)

      end if

;

; Calculate average, and get min and max.

;

      if(.not.any(ismissing(idx))) then

        yvalues(nd,i)    = avg(npp_data(idx))

        mn_yvalues(nd,i) = min(npp_data(idx))

        mx_yvalues(nd,i) = max(npp_data(idx))

        count = dimsizes(idx)

      else

        count            = 0

        yvalues(nd,i)    = yvalues@_FillValue

        mn_yvalues(nd,i) = yvalues@_FillValue

        mx_yvalues(nd,i) = yvalues@_FillValue

      end if

;

; Print out information.

;

      print(data_types(nd) + ": " + count + " points, avg = " + yvalues(nd,i))

      print("Min/Max:  " + mn_yvalues(nd,i) + "/" + mx_yvalues(nd,i))

;

; Clean up for next time in loop.

;

      delete(idx)

    end do

    delete(data)

    delete(npp_data)

  end do

  xvalues@long_name = "Mean Annual precipitation (m/year)"

  yvalues@long_name = "NPP (g C/m2/year)"                 

;

; Start the graphics.

;

; wks = gsn_open_wks("x11","npp")

  wks = gsn_open_wks("png","npp")

  res             = True

  res@tiMainString = "Observed vs i01.03cn"

; res@tiMainString = "Observed vs i01.04casa"

  res@gsnMaximize = False

  res@gsnDraw     = False

  res@gsnFrame    = False

  res@xyMarkLineMode = "Markers"

  res@xyMarkerSizeF   = 0.014

  res@xyMarker       = 16

; res@xyMarkerColors = (/"Gray25","Gray50"/)

  res@xyMarkerColors = (/"brown","blue"/)

  res@trYMinF        = min(mn_yvalues) - 10.

  res@trYMaxF        = max(mx_yvalues) + 10.

  xy = gsn_csm_xy(wks,xvalues,yvalues,res)

  max_bar = new((/2,nx/),graphic)

  min_bar = new((/2,nx/),graphic)

  max_cap = new((/2,nx/),graphic)

  min_cap = new((/2,nx/),graphic)

  lnres = True

  line_colors = (/"brown","blue"/)

  do nd=0,1

    lnres@gsLineColor = line_colors(nd)

    do i=0,nx-1

      if(.not.ismissing(mn_yvalues(nd,i)).and. \

         .not.ismissing(mx_yvalues(nd,i))) then

;

; Attach the vertical bar, both above and below the marker.

;

        x1 = xvalues(nd,i)

        y1 = yvalues(nd,i)

        y2 = mn_yvalues(nd,i)

        min_bar(nd,i) = gsn_add_polyline(wks,xy,(/x1,x1/),(/y1,y2/),lnres)

        y2 = mx_yvalues(nd,i)

        max_bar(nd,i) = gsn_add_polyline(wks,xy,(/x1,x1/),(/y1,y2/),lnres)

;

; Attach the horizontal cap line, both above and below the marker.

;

        x1 = xvalues(nd,i) - dx4

        x2 = xvalues(nd,i) + dx4

        y1 = mn_yvalues(nd,i)

        min_cap(nd,i) = gsn_add_polyline(wks,xy,(/x1,x2/),(/y1,y1/),lnres)

        y1 = mx_yvalues(nd,i)

        max_cap(nd,i) = gsn_add_polyline(wks,xy,(/x1,x2/),(/y1,y1/),lnres)

      end if

    end do

  end do

  draw(xy)

  frame(wks)

end