How to mark top axis

Hi all,
   Here is my code as follo. I want to mark the top axis with the same tick mark but different labels, such as 10^4 10^3 10^2 10. How should I modify the code? Thanks.

;*************************************************
; spec_3.ncl
;************************************************
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_csm.ncl"
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/contributed.ncl"
load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/shea_util.ncl"
;************************************************
begin
;************************************************
; variable and file handling
;************************************************
   sec1 = "KS" ; define section name
   sec2 = "BS"
   sec3 = "MS"
   sec4 = "LS"
   pic_name = "SCS"+"_spec"
   wks_type = "eps"
   post = "_daily.dat.bak"
   data = asciiread(sec1+post,(/4017,2/),"float")
   x1 = data(:,1)
   data = asciiread(sec2+post,(/4017,2/),"float")
   x2 = data(:,1)
   data = asciiread(sec3+post,(/4017,2/),"float")
   x3 = data(:,1)
   data = asciiread(sec4+post,(/4017,2/),"float")
   x4 = data(:,1)
   
;************************************************
; set function arguments
;************************************************
  iopt = 0 ; detrending opt: 0=>remove mean 1=>remove mean + detrend
  sm = 2 ; smooth: should be at least 3 and odd ;jave
  pct = 0.10 ; percent taper: (0.0 <= pct <= 1.0) 0.10 common.
;************************************************
; calculate spectrum
;************************************************
  dof1 = specx_anal(x1,iopt,sm,pct)
  dof2 = specx_anal(x2,iopt,sm,pct)
  dof3 = specx_anal(x3,iopt,sm,pct)
  dof4 = specx_anal(x4,iopt,sm,pct)

  plt1 = specx_ci(dof1, 0.05, 0.95) ; calc confidence interval
  plt2 = specx_ci(dof2, 0.05, 0.95) ; calc confidence interval
  plt3 = specx_ci(dof3, 0.05, 0.95) ; calc confidence interval
  plt4 = specx_ci(dof4, 0.05, 0.95) ; calc confidence interval

  frq = dof1@frq
;************************************************
; plotting parameters
;************************************************
   wks = gsn_open_wks(wks_type,pic_name) ; Opens a ps file
   plot = new(4,graphic) ; create graphic array

   r = True ; plot mods desired
   r@gsnDraw = False ; do not draw
   r@gsnFrame = False ; do not advance frame
   r@tiYAxisString = "PSD (Sv**2/cpd)" ; yaxis
   r@xyLineThicknesses = (/2.,1.,1.,1./) ; Define line thicknesses
   r@xyDashPatterns = (/0,0,1,1/) ; Dash patterns
   r@trYLog = True
   r@trXLog = True
   r@trYMinF = 0.01
   r@trXMaxF = 0.2
   r@trXMinF = 0.0001
   r@xyLineColors = (/"foreground","blue","red","red"/)

   r@tmXUseBottom = False
; r@tmXTOn = True
; r@tmXTLabelsOn = True
   r@tmXTMode = "Explicit"
   r@tmXTValues = (/1e-4,1e-3,1e-2,1e-1/)
   r@tmXTLabels = (/"10~S~4","10~S~3","10~S~2","10~S~1"/)
   r@tmXTMinorOn = True

; r@tmXTStyle = "Log"
   r@vpWidthF = 0.5
   r@vpHeightF = 0.3
;************************************************
; first plot
;************************************************
; plot(0)=gsn_csm_xy(wks, dof1@frq, sdof@spcx, r) ; create plot
   r@tiMainString = sec1 ; title
   plot(0)=gsn_csm_xy(wks, frq, plt1, r) ; create plot
;***********************************************
; second plot: Generate quick-n-dirty plot showing
; 5 and 95% "red noise" confidence
; bounds
;***********************************************
   r@tiYAxisString = "" ; yaxis
   r@tiMainString = sec2 ; title
   plot(1) = gsn_csm_xy(wks,frq, plt2,r)
;***********************************************
; Third Plot: Generate fancier plot showing
; "red noise" confidence bounds
; (a) solid for spectrum and Markov,
; (b) dash for bounds
;***********************************************
   r@tiXAxisString = "Frequency (cpd)" ; xaxis
   r@tiYAxisString = "PSD (Sv**2/cpd)" ; yaxis
   r@tiXAxisOn = True
   r@tiMainString = sec3 ; title
   plot(2) = gsn_csm_xy(wks,frq, plt3,r)
;***********************************************
; Fouth Plot: Generate color plot showing
; "red noise" confidence bounds
;***********************************************
   r@tiYAxisString = "" ; yaxis
  r@tiMainString = sec4 ; title
   plot(3) = gsn_csm_xy(wks,frq, plt4,r)
;***********************************************
   res_P = True ; panel mods desired
   res_P@gsnMaximize = True ; blow up plot
   res_P@vpWidthF = 0.3
   res_P@vpHeightF = 0.8

   gsn_panel(wks,plot,(/2,2/),res_P) ; create panel plots
end



2013-11-15



Xueming Zhu 朱学明
Key Laboratory of Research on Marine Hazards Forecasting (LoMF), SOA
National Marine Environmental Forecasting Center (NMEFC)
No.8, Dahuisi Road, Haidian District, Beijing, 100081
People's Republic of China
Tel:+86-10-82481923

_______________________________________________
ncl-talk mailing list
List instructions, subscriber options, unsubscribe:
http://mailman.ucar.edu/mailman/listinfo/ncl-talk
Received on Thu Nov 14 22:14:09 2013