function taylor_diagram (wks:graphic ,RATIO[*][*]:numeric, CC[*][*]:numeric \

                                     ,rOpts:logical)

;--------------------------------------------------------------------

; This version of taylor_diagram supports "paneling"

; It requires NCL version 4.2.0.a034 because it uses "gsn_create_legend"

;--------------------------------------------------------------------

;

; Generate a Taylor Diagram:

; Generate Multiple Aspects of Model Performance in a Single Diagram

; Taylor, K. E., J. Geophys. Res., 106, D7, 7183-7192, 2001

;

; An example:

; http://www.grida.no/climate/ipcc_tar/wg1/fig8-4.htm

;

; This expects one or more datasets. The left dimension 

; is the number of datasets. The rightmost is the number of pts.

;

; Markers are at: 

; http://www.ncl.ucar.edu/Document/Graphics/Resources/gs.shtml

;

; By default, the function can handle up to 10 variable comparisons..

; To expand ...  modify the 'Colors' and 'Markers' attributes.

; The user can change / add some default settings.

;

; The defaults that the user can modify:

;

; rOpts                 = True 

;                                  ; 'made-up' resources

; rOpts@Colors          =  (/ "blue" , "red", "green", "cyan", "black" \

;                           , "torquoise", "brown", "yellow"/)

; rOpts@Markers         =  (/ 2, 3, 6, 14, 9, 12, 7, 4/) ; Marker Indices

; rOpts@markerTxOffset  = 0.0175   ; offset for text above marker

; rOpts@stnRad          = (/ 1. /) ;  (/ 0.50, 0.75, 1.5 /) 

; rOpts@centerDiffRMS   = False    ;  True mean draw additional radii from REF 

; rOpts@caseLabelsFontHeightF = 0.05

; rOpts@varLabelsFontHeightF  = 0.013

; rOpts@varLabelsYloc         = 0.65

; rOpts@legendWidth           = 0.015

; rOpts@legendHeight          = 0.030*nCase

; rOpts@taylorDraw            = True

; rOpts@taylorFrame           = True

;

;                                  ; standard NCL resources

; rOpts@tiMainString    = "Taylor" ; not using title makes plot bigger

; rOpts@gsMarkerSizeF   = 0.0085   ; marker size   

; rOpts@gsMarkerThicknessF = 1.0

; rOpts@txFontHeightF   = 0.0125   ; text size 

; rOpts@tiMainFontHeightF = 0.0225 ; tiMainString size

;

; It returns to the user a graphic object containing the 

; Taylor background and plotted x/y pts.

; This graphic object contains a simple Taylor background appropriate

; for standardized data and the markers for the datasets.

; ==================================================================

; This version allows paneling:

;      The 'cumbersome' "dum" variables were added by 

;      Adam Phillips to allow paneling via "gsn_add_?".

; ==================================================================

begin

  dimR                  = dimsizes(RATIO)

  nCase                 = dimR(0)    ; # of cases [models] 

  nVar                  = dimR(1)    ; # of variables

                                     ; x/y coordinates for plotting

  X    = new ( (/nCase,nVar/) , typeof(RATIO) )

  Y    = new ( (/nCase,nVar/) , typeof(RATIO) )

  do nc=0,nCase-1

     angle      = acos( CC(nc,:) )   ; array operation                                    

     X(nc,:)    = RATIO(nc,:)*cos( angle )     

     Y(nc,:)    = RATIO(nc,:)*sin( angle )    

  end do

  xyMin                 = 0.  

  xyOne                 = 1.00

  xyMax                 = 1.65

  xyMax_Panel           = xyMax+ 0.10            ; paneling purposes

  if (rOpts .and. isatt(rOpts,"txFontHeightF"))  then 

      FontHeightF       = rOpts@txFontHeightF    ; user wants to specify size

  else

      FontHeightF       = 0.0175

  end if

; ----------------------------------------------------------------

; Part 1:

; base plot: Based upon request of Mark Stevens

; basic x-y and draw the 1.0 observed and the outer curve at 1.65

; ----------------------------------------------------------------

  rxy                   = True       

  rxy@gsnDraw           = False

  rxy@gsnFrame          = False

  rxy@vpHeightF         = 0.65

  rxy@vpWidthF          = 0.65

  rxy@tmYLBorderOn      = False

  rxy@tmXBBorderOn      = False

; rxy@tiYAxisString     = "Standardized Deviations (Normalized)"

  rxy@tiYAxisString     = "Standardized Deviations"

  rxy@tiYAxisFontHeightF= FontHeightF                        ; default=0.025 

  rxy@tmXBMode          = "Explicit" 

  rxy@tmXBValues        = (/0.0,0.25,0.50,0.75,1.00,1.25,1.5/)    ; major tm

                                                                  ; default  "OBS" or "REF"

 ;rxy@tmXBLabels        = (/"0.00","0.25","0.50","0.75","REF" ,"1.25","1.50"/)

  rxy@tmXBLabels        = (/"    ","0.25","0.50","0.75","REF" ,"1.25","1.50"/)

  if (rOpts .and. isatt(rOpts,"OneX") )  then                     ; eg: rOpts@OneX="1.00" 

     ;rxy@tmXBLabels        = (/"0.00","0.25","0.50","0.75",rOpts@OneX,"1.25","1.50"/)

      rxy@tmXBLabels        = (/"    ","0.25","0.50","0.75",rOpts@OneX,"1.25","1.50"/)

  end if

  rxy@tmXBMajorLengthF  = 0.015      ; default=0.02 for a vpHeightF=0.6

  rxy@tmXBLabelFontHeightF = FontHeightF

  rxy@tmXBMinorOn       = False

  rxy@trXMaxF           = xyMax_Panel

  rxy@tmYLMode          = "Manual"

  rxy@tmYLMinorOn       = False

  rxy@tmYLMajorLengthF  = rxy@tmXBMajorLengthF

  rxy@tmYLLabelFontHeightF = FontHeightF

  rxy@tmYLMode          = "Explicit" 

  rxy@tmYLValues        = (/0.0, .25,0.50, 0.75, 1.00, 1.25, 1.5/) ; major tm

  rxy@tmYLLabels        = (/"0.00","0.25","0.50","0.75","1.00","1.25","1.50"/)

 ;rxy@tmYLLabels        = (/"    ","0.25","0.50","0.75","1.00","1.25","1.50"/)

  rxy@trYMaxF           = xyMax_Panel

  rxy@tmYRBorderOn      = False

  rxy@tmYROn            = False      ; Turn off right tick marks.

  rxy@tmXTBorderOn      = False

  rxy@tmXTOn            = False      ; Turn off right tick marks.

  rxy@xyDashPatterns    = (/ 0 /)    ; line characteristics (dash,solid)

  rxy@xyLineThicknesses = (/ 2./)    ; choose line thickness

  rxy@gsnFrame          = False      ; Don't advance the frame.

                                            ; create outer 'correlation axis'

  npts    = 200                        ; arbitrary

  xx      = fspan(xyMin,xyMax,npts) 

  yy      = sqrt(xyMax^2 - xx^2    )   ; outer correlation line (xyMax)

  sLabels = (/"0.0","0.1","0.2","0.3","0.4","0.5","0.6" \ ; correlation labels

             ,"0.7","0.8","0.9","0.95","0.99","1.0"     /); also, major tm

  cLabels = stringtofloat(sLabels)

  rad     = 4.*atan(1.0)/180.

  angC    = acos(cLabels)/rad                     ; angles: correlation labels

  if (rOpts .and. isatt(rOpts,"tiMainString")) then

      rxy@tiMainString      = rOpts@tiMainString

     ;rxy@tiMainOffsetYF    = 0.015               ; default  0.0

      if (isatt(rOpts,"tiMainFontHeightF")) then

           rxy@tiMainFontHeightF = rOpts@tiMainFontHeightF

      else

           rxy@tiMainFontHeightF = 0.0225         ; default  0.025              

      end if

  end if

;;if (rOpts .and. isatt(rOpts,"gsnCenterString")) then

;;    rxy@gsnCenterString  = rOpts@gsnCenterString      ; only gsn_csm_xy

;;end if

  taylor  = gsn_xy(wks,xx,yy,rxy)                 ; Create and draw XY plot.

  rsrRes  = True

  rsrRes@gsLineThicknessF  = rxy@xyLineThicknesses(0)  ; line thickness

  rsrRes@gsLineDashPattern = 0                    ; solid line pattern

                                                  ; draw x and y to xyMax

  dum0 = gsn_add_polyline(wks,taylor,(/0.,  0. /),(/0.,xyMax/), rsrRes)

  dum1 = gsn_add_polyline(wks,taylor,(/0.,xyMax/),(/0.,  0. /), rsrRes)

  xx   = fspan(xyMin, xyOne ,npts)                ; draw 1.0 standard radius

  yy   = sqrt(xyOne - xx^2)   

  rsrRes@gsLineDashPattern = 1                    ; dashed line pattern

  rsrRes@gsLineThicknessF  = rxy@xyLineThicknesses(0)  ; line thickness

  dum2 = gsn_add_polyline(wks,taylor,xx,yy, rsrRes)

  delete(xx)

  delete(yy)

  if (rOpts .and. isatt(rOpts,"stnRad") ) then

      rsrRes@gsLineThicknessF  = 1   ; rxy@xyLineThicknesses(0)  

      nStnRad = dimsizes(rOpts@stnRad)

      dum3  = new(nStnRad,graphic)

      do n=0,nStnRad-1

         rr = rOpts@stnRad(n)

         xx = fspan(xyMin, rr ,npts) 

         yy = sqrt(rr^2   - xx^2)   

         dum3(n) = gsn_add_polyline(wks,taylor,xx,yy, rsrRes)

      end do

      taylor@$unique_string("dum")$ = dum3

      delete(xx)

      delete(yy)

  end if

  getvalues taylor                                ; get style info from taylor

    "tmYLLabelFont"        : tmYLLabelFont        ; use for correlation axis

    "tmYLLabelFontHeightF" : tmYLLabelFontHeightF

  end getvalues

; ----------------------------------------------------------------

; Part 2:

; Correlation labels

; ----------------------------------------------------------------

  radC    = xyMax                                  ; for correlation labels

  xC      = radC*cos(angC*rad)

  yC      = radC*sin(angC*rad)

; added to get some separation

  xC      = xC + 0.020*cos(rad*angC)

  yC      = yC + 0.060*sin(rad*angC)

  txRes               = True                      ; text mods desired

  txRes@txFontHeightF = FontHeightF               ; match YL 

  txRes@tmYLLabelFont = tmYLLabelFont             ; match YL

  txRes@txAngleF      = -45.

  if (.not.isatt(rOpts,"drawCorLabel") .or. rOpts@drawCorLabel) then 

      dum4 = gsn_add_text(wks,taylor,"Correlation",1.30,1.30,txRes)

	 taylor@$unique_string("dum")$ = dum4

  end if

  txRes@txAngleF      = 0.0 

  txRes@txFontHeightF = FontHeightF*0.50          ; bit smaller

;;dum0 = gsn_add_text(wks,taylor,"OBSERVED",1.00,0.075,txRes)

  plRes               = True

  plRes@gsLineThicknessF = 2.

  txRes@txJust        = "CenterLeft"              ; Default="CenterCenter".

  txRes@txFontHeightF = FontHeightF               ; match YL 

 ;txRes@txBackgroundFillColor = "white"

  tmEnd = 0.975

  radTM = xyMax*tmEnd                             ; radius end: major TM 

  xTM   = new( 2 , "float")

  yTM   = new( 2 , "float")

  dum5 = new(dimsizes(sLabels),graphic)

  dum6 = dum5

  do i=0,dimsizes(sLabels)-1                      ; Loop to draw strings

    txRes@txAngleF = angC(i)

    dum5(i) = gsn_add_text(wks, taylor, sLabels(i),xC(i),yC(i),txRes) ; cor label

    xTM(0)   = xyMax*cos(angC(i)*rad)             ; major tickmarks at

    yTM(0)   = xyMax*sin(angC(i)*rad)             ; correlation labels

    xTM(1)   = radTM*cos(angC(i)*rad)             

    yTM(1)   = radTM*sin(angC(i)*rad)

    dum6(i) = gsn_add_polyline(wks,taylor,xTM,yTM,plRes)

  end do

                                                  ; minor tm locations

  mTM     = (/0.05,0.15,0.25,0.35,0.45,0.55,0.65 \ 

             ,0.75,0.85,0.91,0.92,0.93,0.94,0.96,0.97,0.98  /)

  angmTM  = acos(mTM)/rad                         ; angles: correlation labels

  radmTM  = xyMax*(1.-(1.-tmEnd)*0.5)             ; radius end: minor TM 

  dum7 = new(dimsizes(mTM),graphic)

  do i=0,dimsizes(mTM)-1                          ; manually add tm

    xTM(0)   = xyMax*cos(angmTM(i)*rad)           ; minor tickmarks

    yTM(0)   = xyMax*sin(angmTM(i)*rad)

    xTM(1)   = radmTM*cos(angmTM(i)*rad)          

    yTM(1)   = radmTM*sin(angmTM(i)*rad)

    dum7(i)  = gsn_add_polyline(wks,taylor,xTM,yTM,plRes)

  end do

                                                  ; added for Wanli

  if (rOpts .and. isatt(rOpts,"ccRays") ) then

      angRL = acos(rOpts@ccRays)/rad             ; angles: radial lines

      rlRes = True

      rlRes@xyDashPattern    = 4  ; line pattern

      rlRes@xyLineThicknessF = 1  ; choose line thickness

      dum8 = new(dimsizes(angRL),graphic)

      do i=0,dimsizes(angRL)-1

         xRL     = xyMax*cos(angRL(i)*rad)

         yRL     = xyMax*sin(angRL(i)*rad)

         dum8(i) = gsn_add_polyline(wks,taylor,(/0, xRL /),(/0,  yRL  /),rlRes)

      end do

      taylor@$unique_string("dum")$ = dum8

  end if

; ----------------------------------------------------------------

; Part 3:

; Concentric about 1.0 on XB axis

; I think this is correct. Still test mode.

; ----------------------------------------------------------------

  if (rOpts .and. isatt(rOpts,"centerDiffRMS") \

            .and. rOpts@centerDiffRMS) then

      respl                    = True                ; polyline mods desired

      respl@gsLineThicknessF   = 1.0                 ; line thickness

      respl@gsLineColor        = "Black"             ; line color     

      respl@gsLineDashPattern  = 2                   ; short dash lines

      dx   = 0.25

      ncon = 4                                       ; 0.75, 0.50, 0.25, 0.0

      npts = 100                                     ; arbitrary

      ang  = fspan(180,360,npts)*rad

      dum9 = new(ncon,graphic)

      do n=1,ncon 

         rr  = n*dx            ; radius from 1.0 [OBS] abscissa

         xx  = 1. + rr*cos(ang)

         yy  = fabs( rr*sin(ang) )

         if (n.le.2) then

             dum9(n-1) = gsn_add_polyline(wks,taylor,xx,yy,respl)

         end if

         if (n.eq.3) then

             n3 = floattointeger( 0.77*npts ) 

             dum9(n-1) = gsn_add_polyline(wks,taylor,xx(0:n3),yy(0:n3),respl)

         end if

         if (n.eq.4) then

             n4 = floattointeger( 0.61*npts ) 

             dum9(n-1) = gsn_add_polyline(wks,taylor,xx(0:n4),yy(0:n4),respl)

         end if

      end do

      delete(ang)

      delete(xx)

      delete(yy)

      taylor@$unique_string("dum")$ = dum9

  end if

; ---------------------------------------------------------------

; Part 4:

; generic resources that will be applied to all users data points

; of course, these can be changed 

; http://www.ncl.ucar.edu/Document/Graphics/Resources/gs.shtml

; ---------------------------------------------------------------

  if (rOpts .and. isatt(rOpts,"Markers")) then

      Markers = rOpts@Markers

  else

      Markers = (/ 4, 6, 8,  0, 9, 12, 7, 2, 11, 16/) ; Marker Indices

  end if

  if (rOpts .and. isatt(rOpts,"Colors")) then

      Colors  = rOpts@Colors

  else

      Colors  = (/ "red", "blue", "green", "cyan", "orange" \

                 , "torquoise", "brown", "yellow", "purple", "black"/)

  end if

  if (rOpts .and. isatt(rOpts,"gsMarkerThicknessF")) then

      gsMarkerThicknessF = rOpts@gsMarkerThicknessF

  else

      gsMarkerThicknessF = 1.0

  end if

  if (rOpts .and. isatt(rOpts,"gsMarkerSizeF")) then

      gsMarkerSizeF      = rOpts@gsMarkerSizeF

  else

      gsMarkerSizeF      = 0.0085                  ; Default: 0.007

  end if

  gsRes = True

  gsRes@gsMarkerThicknessF = gsMarkerThicknessF      ; default=1.0

  gsRes@gsMarkerSizeF      = gsMarkerSizeF           ; Default: 0.007 

  ptRes = True                        ; text options for points

  ptRes@txJust             = "BottomCenter"; Default="CenterCenter".

  ptRes@txFontThicknessF   = 1.2      ; default=1.00

  ptRes@txFontHeightF      = 0.0125   ; default=0.05

  if (rOpts .and. isatt(rOpts,"txFontHeightF")) then

      ptRes@txFontHeightF  = rOpts@txFontHeightF  

  end if

  markerTxYOffset          = 0.0175   ; default

  if (rOpts .and. isatt(rOpts,"markerTxYOffset")) then

      markerTxYOffset = rOpts@markerTxYOffset             ; user defined offset

  end if

  dum10 = new((nCase*nVar),graphic)

  dum11 = dum10

  do n=0,nCase-1

     gsRes@gsMarkerIndex   = Markers(n)             ; marker style (+)

     gsRes@gsMarkerColor   = Colors(n)              ; marker color

     ptRes@txFontColor     = gsRes@gsMarkerColor

    do i=0,nVar-1

       dum10(n*nVar+i) = gsn_add_polymarker(wks,taylor,X(n,i),Y(n,i),gsRes) 

       dum11(n*nVar+i) = gsn_add_text(wks,taylor,(i+1),X(n,i),Y(n,i)+markerTxYOffset,ptRes)

    end do

  end do

; ---------------------------------------------------------------

; Part 5: ; add case legend and variable labels

; ---------------------------------------------------------------

  if (rOpts .and. isatt(rOpts,"caseLabels")) then 

      if (isatt(rOpts,"caseLabelsFontHeightF")) then

          caseLabelsFontHeightF = rOpts@caseLabelsFontHeightF

      else

          caseLabelsFontHeightF = 0.05  

      end if

      lgres                    = True

      lgres@lgMarkerColors     = Colors        ; colors of markers

      lgres@lgMarkerIndexes    = Markers       ; Markers 

      lgres@lgMarkerSizeF      = gsMarkerSizeF ; Marker size

      lgres@lgItemType         = "Markers"     ; draw markers only

      lgres@lgLabelFontHeightF = caseLabelsFontHeightF  ; font height of legend case labels

      if (isatt(rOpts,"legendWidth")) then

          lgres@vpWidthF       = rOpts@legendWidth

      else

          lgres@vpWidthF       = 0.15           ; width of legend (NDC)

      end if

      if (isatt(rOpts,"legendHeight")) then

          lgres@vpHeightF      = rOpts@legendHeight

      else   

          lgres@vpHeightF      = 0.030*nCase   ; height of legend (NDC)

      end if

      lgres@lgPerimOn          = False         ; turn off perimeter

      nModel                   = dimsizes( rOpts@caseLabels )

      lbid = gsn_create_legend(wks,nModel,rOpts@caseLabels,lgres)

      amres = True

      amres@amParallelPosF     =  0.35           

      amres@amOrthogonalPosF   = -0.35             

      annoid1 = gsn_add_annotation(taylor,lbid,amres)	; add legend to plot

  end if

  if (rOpts .and. isatt(rOpts,"varLabels")) then 

      nVar    = dimsizes(rOpts@varLabels)

      if (isatt(rOpts,"varLabelsFontHeightF")) then

          varLabelsFontHeightF = rOpts@varLabelsFontHeightF

      else

          varLabelsFontHeightF = 0.013

      end if

      txres = True

      txres@txFontHeightF = varLabelsFontHeightF

      txres@txJust = "CenterLeft"              ; justify to the center left

     ;delta_y = 0.02       

      delta_y = 0.06   

      if (rOpts .and. isatt(rOpts,"varLabelsYloc")) then

          ys  = rOpts@varLabelsYloc            ; user specified

      else

          ys  = max( (/nVar*delta_y , 0.30/) )

      end if

      do i = 1,nVar     

         if (i.eq.1) then

             dum12 = new(nVar,graphic)

	 end if

         dum12(i-1) = gsn_add_text(wks,taylor,i+" - "+rOpts@varLabels(i-1), .125,ys,txres)

         ys = ys- delta_y

      end do

      taylor@$unique_string("dum")$ = dum12

  end if

  taylor@$unique_string("dum")$ = dum0   ; x-axis

  taylor@$unique_string("dum")$ = dum1   ; y-axis

  taylor@$unique_string("dum")$ = dum2   ; 1.0 std curve

  taylor@$unique_string("dum")$ = dum5   ; labels [COR]

  taylor@$unique_string("dum")$ = dum6   ; major tm [COR]

  taylor@$unique_string("dum")$ = dum7   ; minor tm

  taylor@$unique_string("dum")$ = dum10  ; markers

  taylor@$unique_string("dum")$ = dum11  ; text

  if (.not.isatt(rOpts,"taylorDraw") .or. \

     (isatt(rOpts,"taylorDraw") .and. rOpts@taylorDraw)) then 

	draw(taylor)

  end if

  if (.not.isatt(rOpts,"taylorFrame") .or. \

     (isatt(rOpts,"taylorFrame") .and. rOpts@taylorFrame)) then 

	frame(wks)

  end if

  return(taylor)

end