NCL Frequently Asked Questions (FAQ)

Where can I download NCL? · gsnMaximize

    setenv NCARG_ROOT /usr/local
    set path=(/usr/local/bin $path)

    export NCARG_ROOT=/usr/local
    export PATH=(/usr/local/bin $PATH)

    setenv DISPLAY :0.0
    setenv DISPLAY 128.117.14.12:0
    setenv DISPLAY localhost:13.0

    export DISPLAY=:0.0
    export DISPLAY=128.117.14.12:0
    export DISPLAY=localhost:13.0

ncl

 Copyright (C) 1995-2008 - All Rights Reserved
 University Corporation for Atmospheric Research
 NCAR Command Language Version 5.0.1
 The use of this software is governed by a License Agreement.
 See http://www.ncl.ucar.edu/ for more details.
ncl 0>

  ncl myscript.ncl

Variable: x
Type: float
Total Size: 80 bytes
            20 values
Number of Dimensions: 1
Dimensions and sizes:   [20]
Coordinates: 
(0)      0
(1)     0.5263158
(2)     1.052632
(3)     1.578947
(4)     2.105263
(5)     2.631579
. . .

Variable: x
Type: float
Total Size: 80 bytes
            20 values
Number of Dimensions: 1
Dimensions and sizes:   [20]
Coordinates: 
 0
0.5263158
1.052632
1.578947
2.105263
2.631579
. . .

  ncl -x your_script.ncl

  ldd `which ncl`

  libnc-dap.so.3 => /usr/local/lib/libnc-dap.so.3 (0x0000002a95557000)
  libdap.so.6 => /usr/local/lib/libdap.so.6 (0x0000002a956ee000)
  libdapclient.so.1 => /usr/local/lib/libdapclient.so.1 (0x0000002a958b9000)

  url = "http://test.opendap.org/opendap/data/nc/" 
  filename = "123.nc" 
  exists = isfilepresent(url+filename) 
  if(.not.exists) then 
    print("OPeNDAP isfilepresent test unsuccessful.") 
    print("Either you don't have the appropriate permissions to access OPeNDAP servers, or NCL does not have OPeNDAP capabilities on this system") 
    status_exit(1) 
  else 
    print("OPeNDAP isfilepresent test successful.") 
    f = addfile(url + filename,"r") 
    vars = getfilevarnames(f) 
    vars_out = (/"l","j","i","cross","aloan","shot","order","bears"/) 

    sqsort(vars) 
    sqsort(vars_out) 

    print(vars)         ; These two lists should
    print(vars_out)     ; be the same.
  end if 

; Here is a comment before a command that assigns a variable.
  x = 5.

  x = 5.     ; This comment can be at the end of a line

;
; This is a block of comments,
; each of which must be 
; preceded by its own semicolon
;

  x = (/"This", "is", "a", "long", "array", "of", "strings", "that", \
        "we", "can", "continue", "on", "a", "new", "line", "with", "a", \
        "\", "character."/)

; Can use \ for arithmetic expressions
  output(i,1:n-2) = (p4)*(var( i-1, 1 : n-2 ) + var( i,   2 : n-1)  + \
                          var( i+1, 1 : n-2 ) + var( i,   0 : n-3)) + \
                    (q4)*(var( i-1, 0 : n-3 ) + var( i-1, 2 : n-1)  + \
                          var( i+1, 2 : n-1 ) + var( i+1, 0 : n-3))

  x   = 3.14
  str = "" + x

  x = new(5, float, "No_FillValue")

  x = 1.d      ; double, x = 1d   (also acceptable)
  l = 1l       ; long
  s = 1s       ; short

  quote = inttochar(34)
  print("The word " + quote + "string" + quote + " has double quotes around it.")
  print("'Single' quotes are no big deal.")

    x = - 3^2

    x = (-3)^2

    print(- (3+2)^2)      ----> yields 25

    print(- ((3+2)^2))    ---->  yields -25

    x = 0 - 3^2      ; equivalent to  x = (0) - (3^2)

  ii  = ispan(0,100,1)
  iis = sprinti("%0.3i",ii)   ; "000", "001", ... "100"

    datestr = systemfunc("date")

    filenames = systemfunc("ls *.txt")

  month    = 1
  day      = 21
  year     = 2002
  date_str = "The date is " + month + "/" + day + "/" + year

  do i=1,10
    filename = "sw" + sprinti("%0.3i",i) + ".out"
    ...do something with filename...
  end do

    env_str = getenv("PATH")

  N    = 5
  M    = 7
  ave  = 0.0
  std  = 5.0
  x    = random_normal(ave, std, (/N,M/))  

  write_matrix(x, "5f7.2", False)

   4.35   4.39   0.27  -3.35  -6.90
   4.36   4.66   3.77  -1.66   4.06
   9.73  -5.84   0.89   8.46  10.39
   4.91   4.59  -3.09   7.55   4.56
   1.77   3.68   5.08   0.14  -5.63
  -0.63 -14.12  -2.51   1.76  -1.43
  -4.29   0.07   5.85   0.87   8.65

  ncl_convert2nc your_file.xxx

  ncl_filedump ced1.lf00.t00z.ega.grb
  ncl_filedump -v PRES_6_SFC -ftime ced1.lf00.t00z.ega.grb

   ncendef: ncid 0: NetCDF: One or more variable sizes violate format
                            constraints

    ncl_convert2nc U12345.grb -L

spherical = new(1,"character") 
spherical!0 = "ncl_scalar" 
spherical = integertocharacter(1)
ncid->spherical = spherical 

filevardef(ncid, "spherical","character","ncl_scalar") 
ncld->spherical = integertocharacter(1) 

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

  fils = systemfunc("ls /model/annual*nc")

  f    = addfiles(fils, "r")
  T    = addfiles_GetVar(f,fils,"T")
  printVarSummary(T)

in->Data-Set-14
ncl> print(in->Data-Set-14) 
fatal:Either file (in) isn't defined or variable (Data) is not a variable in the file
fatal:Execute: Error occurred at or near line 24

  print(in->$"Data-Set-14"$)

  var_string = "Data-Set-14"
  print(in->$var_string$)

begin
  grib_file  = addfile("ced1.lf00.t00z.eta.grb","r")  ; Open GRIB file to read
  ncfile_out = addfile("data.nc","c")             ; Open NetCDF file to write

; Write some data to NetCDF file.
  ncfile_out->PRES  = grib_file->PRES_6_SFC 
  ncfile_out->HGT   = grib_file->HGT_6_SFC 
  ncfile_out->A_PCP = grib_file->A_PCP_6_SFC_acc
  ncfile_out->NCPCP = grib_file->NCPCP_6_SFC_acc
  ncfile_out->ACPCP = grib_file->ACPCP_6_SFC_acc
  ncfile_out->CAPE  = grib_file->CAPE_6_SFC
end

;
; Assume the "oceanland30e.asc" file contains a single column of integers,
; 16471 of them. "asciiread" allows you to specify the dimensionality of
; the data, and in this case we are passing dimensions (/91,181/), so
; "ocean1" will be a 2-dimensional array dimensioned 91 x 181, which can
; be verified by printing the dimsizes of "ocean1."
;
  ocean1 = asciiread("oceanland30e.asc",(/91,181/),"integer")
  print(dimsizes(ocean1))

;
; Write out part of "ocean1" to a new ASCII file.  "data.asc" will contain
; 15 integers, since (7:3:2,0:4) is a 3 x 5 array.
;	
  asciiwrite("data.asc",ocean1(7:3:2,0:4))

  N    = 5
  M    = 7
  ave  = 0.0
  std  = 5.0
  x    = random_normal (ave, std, (/N,M/))  

  res = True
  res@fout = "file.txt"
  write_matrix (x, "5f7.2", res)

   4.35   4.39   0.27  -3.35  -6.90
   4.36   4.66   3.77  -1.66   4.06
   9.73  -5.84   0.89   8.46  10.39
   4.91   4.59  -3.09   7.55   4.56
   1.77   3.68   5.08   0.14  -5.63
  -0.63 -14.12  -2.51   1.76  -1.43
  -4.29   0.07   5.85   0.87   8.65

   z = asciiread("file.dat",-1,float)

   z = asciiread("file.dat",-1,"float")

   ncol = 4                            ; number of columns
   nrow = dimsizes(z)/ncol            ; get number of points
   znew = onedtond(z,(/nrow,ncol/))   ; znew will be nrow x ncol

    ncol = 4
    nrow = stringtointeger(systemfunc("wc -l wgt"))  ; "wc -l" returns the #
                                                     ; of lines in a file
    z = asciiread("file.dat",(/nrow,ncol/),"float")

  setfileoption("bin","ReadByteOrder","LittleEndian")
  v = cbinread("data.littleEndian.bin",-1,"float")

  setfileoption("bin","WriteByteOrder","BigEndian")
  cbinwrite("data.bigEndian.bin",v)

   ncendef: ncid 0: NetCDF: One or more variable sizes violate format
                            constraints

  a = addfile("swath.hdf.hdfeos","r")

begin
  ...
  f = addfile("newfile.nc","w")
  ...write stuff to file pointed to by 'f'.
  delete(f)
end

 CDC_URL  = "http://www.cdc.noaa.gov/cgi-bin/opendap/nph-nc/Datasets/" ; generic CDC
 CDC_FILP = "ncep.reanalysis.dailyavgs/pressure/air.2005.nc"     ; data path

 filp = CDC_URL + CDC_FILP
 if (isfilepresent(filp)) then
   fp = addfile(filp,"r")
 else
   print("============================================")
   print("CDC_URL : "+CDC_URL)
   print("CDC_FILP: "+CDC_FILP)
   print("does not exist: message from NCL script")
   print("============================================")
   exit
 end if

 x = fp->FOO

  x = (/1,2,3,-999,5,6,7,-999,-999,10/)
  x@_FillValue = -999

x
x
  is_msg = any(ismissing(data)))
  if(is_msg) then
    print("'data' contains missing values.")
  else
    print("'data' doesn't contain any missing values.")
  end if

  num_msg = num(ismissing(data)))
  print("data contains " + num_msg + " missing values.")

  data@_FillValue = -999

  data@_FillValue = data@missing_value
  delete(data@missing_value)      ; not necessary, just cleaning up

x
y
   x = (/(/(/2,3/), (/4,5/), (/1,2/)/), (/(/3,8/), (/1,4/), (/0,2/)/)/)
   y = avg(x)

  temp!0 = "time"
  temp!1 = "lat"
  temp!2 = "lon"
  hourly_avg_temp = dim_avg(temp(lat|:,lon|:,time|:))

hourly_avg_temp
temp
  NX = 21
  NY = 21

; Define the input data arrays.
  x = (/0.00, 1.00, 0.00, 1.00, 0.40, 0.75/)
  y = (/0.00, 0.00, 1.00, 1.00, 0.20, 0.65/)
  z = (/0.00, 0.00, 0.00, 0.00, 1.25, 0.80/)

; Define the output grid.
  xc = 1./(NX-1.) 
  xo = ispan(0,NX-1,1) * xc

  yc = 1./(NY-1.) 
  yo = ispan(0,NY-1,1) * yc

; Do the gridding using natgrid. "natout" will be a 2-dimensional array
; dimensioned 21 x 21.
  natout = natgrid(x, y, z, xo, yo)
  print(natout)

; Do the gridding using dsgrid2. "dsout" will be a 2-dimensional array
; dimensioned 21 x 21.
  dsout = dsgrid2(x, y, z, xo, yo)
  print(dsout)

  NX = 21
  NY = 21
  NZ = 21
  x = (/0.00, 1.00, 0.00, 1.00, 0.40, 0.75/)
  y = (/0.00, 0.00, 1.00, 1.00, 0.20, 0.65/)
  z = (/0.00, 0.00, 0.00, 0.00, 1.25, 0.80/)
  u = x*x + y*y + z*z

  xo = new((/NX/),float)
  yo = new((/NY/),float)
  zo = new((/NZ/),float)

;
; Create the output grid.
;
  xmin = -2.0
  ymin = -2.0
  zmin = -2.0
  xmax =  2.0
  ymax =  2.0
  zmax =  2.0

  ii = fspan(0,20.,21)
  xo = xmin + (ii/(NX-1)) * (xmax-xmin)
  yo = ymin + (ii/(NY-1)) * (ymax-ymin)
  zo = zmin + (ii/(NZ-1)) * (zmax-zmin)

;
; Interpolate.  "output" will be a 3-dimensional grid dimensioned 21x21x21.
;
  output = dsgrid3(x, y, z, u, xo, yo, zo)
  print(output)

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

  data = generate_2d_array(10, 10, -19.69, 15.82, 0, (/129,129/))

  wks = gsn_open_wks("x11","max")

  plot = gsn_contour(wks,data,False)

  res             = True
  res@gsnMaximize = True
  plot = gsn_contour(wks,data,res)

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

  wks = gsn_open_wks("ncgm","gsn_draw_colormap")
  gsn_draw_colormap(wks)   ; Draw the default colormap

  gsn_define_colormap(wks,"hotres")   ; Change color map and
  gsn_draw_colormap(wks)              ; draw it.

  res@mpCenterLonF = (res@mpMinLonF + res@mpMaxLonF)/2.

    *Font : helvetica

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

  wks = gsn_open_wks("x11","font")   ; Open an X11 workstation.

  y = (/1,3,-1,-2,0,2,3/)
  x = ispan(0,dimsizes(y)-1,1)

  res = True
  res@tiMainString  = "This is an XY plot"
  res@tiXAxisString = "X values"
  res@tiYAxisString = "Y values"

  xy = gsn_xy(wks,x,y,res)   ; Create and draw an XY plot.

! Change all fonts to times-bold
*Font : times-bold

    *TextFuncCode : ~

*FuncCode
    res@txString = "Time : 0600 hours"

    res@txFuncCode = "~"
    res@txString   = "Time : 0600 hours"

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

begin
  wks = gsn_open_wks("x11","degree")   

  res              = True                     ; plot mods desired

  res@tiMainString = "Example degree (~S~o~N~) symbol"

  res@tmXBMode     = "Explicit"                ; explicit labels 
  res@tmXBValues   = (/  0.2,          0.4,      0.6,          0.8/)
  res@tmXBLabels   = (/"20~F34~0~F~","40~F34~0~F~","60~F34~0~F~","80~F34~0~F~"/)
  res@tmXBLabelFontColor = "Red"

  plot = gsn_blank_plot(wks,res)
end

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

begin

  wks = gsn_open_wks("x11","text")

  res               = True
  res@txJust        = 4
  res@txFont        = 25
  res@txFontHeightF = .1
;
; Explanation of the text string function codes:
;
; :F22: - Select font 22 (Helvetica bold)
; :H-15F35: - Move 15 digitized font units left and select font 35.
; The character "H" in font 35 is an umlaut.
; :H4F22: - Move 4 digitized font units right and select font 22.
; :H-14F35: - Move 14 digitized font units left and select font 35.
; :H3F22: - Move 3 digitized font units right and select font 22.
;
  str1 = ":F22:u:H-15F35:H:H4F22:berho:H-14F35:H:H3F22:hen"

;
; Explanation of the text string function codes:
;
; :F22: - Select font 22.
; :H-16V6F35: - Move 16 digitized units left, 6 digitized units
; up, and select font 35.
; :V-6H5F22: - Move 6 digitized units down and select font 22.
; :H-13F35: - Move 13 digitized units left and select font 35.
; :F22H2: - Select font 22 and move 2 digitized units right.
;
  str2 = ":F22:U:H-16V6F35:H:V-6H5F22:bersta:H-13F35:H:F22H2:nder"

  gsn_text_ndc(wks,str1,0.5,0.7,res)    ; Draw the text string
  gsn_text_ndc(wks,str2,0.5,0.3,res)

  frame(wks)
end 

   res@tiMainString = "Bell (~F19~n~F~)"

begin
  wks = gsn_open_wks("ps","font_test")

  txres = True
  txres@txFontQuality = "low"
  txres@txFontHeightF = 0.04
  txres@txFuncCode    =  ":"
  gsn_text_ndc(wks,"Test PS fonts",.5,.5,txres)
  frame(wks)

  txres@txDirection = "down"
  gsn_text_ndc(wks,"Vertical",.5,.5,txres)
  frame(wks)

  txres@txDirection = "across"
  gsn_text_ndc(wks,                                                   \
    "degree sign:: :F34:0:FC:superscript:: 1.3:F0L1:4:F:10:S:300",    \
    .5,.5,txres)
  frame(wks)
end

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

  wks = gsn_open_wks("x11","viewport")   ; Open an X11 workstation.

  y = (/1,3,-1,-2,0,2,3/)
  x = ispan(0,dimsizes(y)-1,1)

  res = True
  res@vpWidthF  = 0.75
  res@vpHeightF = 0.4

  xy = gsn_csm_xy(wks,x,y,res)   ; Create and draw an XY plot.

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

  wks = gsn_open_wks("x11","viewport")   ; Open an X11 workstation.

  mpres              = True
  mpres@mpShapeMode  = "FreeAspect"    ; Allow the aspect ratio to be changed.
  mpres@gsnMaximize   = True
  mpres@vpWidthF     = 0.8
  mpres@vpHeightF    = 0.8

  map = gsn_map(wks,"CylindricalEquidistant",mpres)

  res@tiMainFontColor = 2     ; index value

  res@tiMainFontColor = "red" ; color name

(/(/0.0,0.0,0.0/),(/1.0,1.0,1.0/),(/1.0,0.0,0.0/),(/0.0,1.0,0.0/),
  (/0.0,0.0,1.0/),(/1.0,1.0,0.0/),(/0.0,1.0,1.0/),(/1.0,0.0,1.0/),
  (/0.5,0.0,0.0/),(/0.5,1.0,1.0/),(/0.0,0.0,0.5/),(/1.0,1.0,0.5/),
  (/0.5,0.0,1.0/),(/1.0,0.5,0.0/),(/0.0,0.5,1.0/),(/0.5,1.0,0.0/),
  (/0.5,0.0,0.5/)/)

  ...
  cmap = (/"(/0.0,0.0,0.0/)","(/1.0,1.0,1.0/)","(/1.0,0.0,0.0/)",\
           "(/0.0,1.0,0.0/)","(/0.0,0.0,1.0/)","(/1.0,1.0,0.0/)",\
           "(/0.0,1.0,1.0/)","(/1.0,0.0,1.0/)","(/0.5,0.0,0.0/)",\
           "(/0.5,1.0,1.0/)","(/0.0,0.0,0.5/)","(/1.0,1.0,0.5/)",\
           "(/0.5,0.0,1.0/)","(/1.0,0.5,0.0/)","(/0.0,0.5,1.0/)",\
           "(/0.5,1.0,0.0/)","(/0.5,0.0,0.5/)",\
           "Olive","Plum","Gold","MediumBlue","LightSlateGray"/)

  wks = gsn_open_wks(...)
  gsn_define_colormap(wks,cmap)
  ...

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

begin

  res = True

;
;  draw_cells draws cells fitting them into a box with lower left 
;  corner (xll,yll) and upper right corner (xur,yur) with nx cells 
;  in x and ny cells in y.  For each call each cell is colored 
;  using increasing indices in cmap, starting with index 0.
;
  procedure draw_cells(wks:graphic, xll:float,  yll:float,  xur:float, \
                       yur:float,   nx:integer, ny:integer,            \
                       cmap[*][3]:numeric)
  begin 
    xinc = (xur-xll)/nx
    yinc = (yur-yll)/ny
    do j=0,ny-1
      plly = yll + j*yinc
      pury = plly + yinc
      do i=0,nx-1
        pllx = xll + i*xinc
        purx = pllx + xinc
        x = (/pllx,purx,purx,pllx,pllx/)
        y = (/plly,plly,pury,pury,plly/)
        res@gsFillColor = i+j*nx
        gsn_polygon_ndc(wks,x,y,res)
      end do
    end do
  end

;
;  Original color map is "black", "red", "green", "blue".
;
  cmap = (/ (/0.,0.,0./), (/1.,0.,0./), (/0.,1.,0./), (/0.,0.,1./) /)
  rlist = True
  rlist@wkColorMap = cmap
  wks_type = "x11"
  wks = gsn_open_wks(wks_type,"cell")
  gsn_define_colormap(wks,cmap)

;
;  Draw color boxes using the original color map.
;
  draw_cells(wks, 0., 0., 1.0, 0.5, 2, 2, cmap)

;
;  Redefine indices 1-3.
;
  NhlSetColor(wks, 1, 0., 1., 1.)  ; cyan
  NhlSetColor(wks, 2, 1., 0., 1.)  ; magenta
  NhlSetColor(wks, 3, 1., 1., 0.)  ; yellow

;
;  Draw color boxes using the redefined color map.
;
  draw_cells(wks, 0., 0.5, 1.0, 1.0, 2, 2, cmap)

  frame(wks)
end

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

  data = generate_2d_array(10, 10, -19.69, 15.82, 0, (/129,129/))

  wks = gsn_open_wks("pdf,"pdfmax")

  res             = True
  res@gsnMaximize = True
  plot = gsn_contour(wks,data,res)

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

  type = "ps"
  type@wkDeviceLowerX = -75   ; These coordinates can be negative.
  type@wkDeviceLowerY = -50
  type@wkDeviceUpperX = 750
  type@wkDeviceUpperY = 950

  wks = gsn_open_wks(type,"psmax")

  res   = True
  blank = gsn_blank_plot(wks,res)

! Make default X11 window larger (adjust as necessary)
*wkWidth   : 800
*wkHeight  : 800

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

; Create some dummy data for the contour plot.
  T = (/ (/  7,  7,   7,   7,   7,   7,   7,   7,   7, 7, 7 /),\
         (/  7,  5,   5,   5,   5,   5,   5,   5,   5, 5, 7 /),\
         (/  7,  5, 999, 999, 999, 999, 999, 999, 999, 5, 7 /),\
         (/  7,  5, 999,   3,   3,   3,   3,   3, 999, 5, 7 /),\
         (/  7,  5, 999,   3,   2,   2,   2,   3, 999, 5, 7 /),\
         (/  7,  5, 999,   3,   2,   1,   2,   3, 999, 5, 7 /),\
         (/  7,  5, 999,   3,   2,   2,   2,   3, 999, 5, 7 /),\
         (/  7,  5, 999,   3,   3,   3,   3,   3, 999, 5, 7 /),\
         (/  7,  5, 999, 999, 999, 999, 999, 999, 999, 5, 7 /),\
         (/  7,  5,   5,   5,   5,   5,   5,   5,   5, 5, 7 /),\
         (/  7,  7,   7,   7,   7,   7,   7,   7,   7, 7, 7 /)/)

  T@_FillValue = 999    ; Set _FillValue.

  wks = gsn_open_wks("x11","contour")
  contour = gsn_contour(wks,T,False)    ; Draw a contour plot.

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

  wks = gsn_open_wks("x11","xy")

  y = (/1,3,-1,-2,0,2,3,0,5,-2,1,0,0,8,10,5,-3/)

  y@_FillValue = 0               ; Set the missing value.

  xy = gsn_y(wks,y,False)        ; Create and draw an XY plot.

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

begin
;
; Generate some dummy data.
;
  level = (/1000, 850, 700, 500, 400, 300, 250, 200, 150, 100/)
  lat   = fspan(-90,90,20)

  nlat  = dimsizes(lat)
  nlev  = dimsizes(level)
  data  = generate_2d_array(10, 12, -20., 17., 0, (/ nlev,nlat/))

  data!0   = "lev"     ; Name the dimensions and
  data!1   = "lat"     ; attach coordinate arrays
  data&lev = level     ; This coordinate array is irregulary spaced
  data&lat = lat

  wks = gsn_open_wks("x11","linear")
  gsn_define_colormap(wks,"rainbow")

; Set up resources.
  res                     = True
  res@gsnMaximize         = True        ; Maximize plot in frame
  res@gsnSpreadColors     = True        ; Span full color map
  res@cnFillOn            = True        ; Turn on contour fill
  res@cnLinesOn           = False       ; Turn off contour lines
  res@lbLabelAutoStride   = True        ; Control labelbar spacing

  res@tiYAxisString       = "Irregularly-spaced values"
  plot = gsn_csm_contour(wks,data,res)  ; Create filled contours

  res@tiYAxisString       = "Y axis linearized"
  res@gsnYAxisIrregular2Linear = True
  plot = gsn_csm_contour(wks,data,res)  ; Create filled contours
end

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

; Create dummy data for XY plot.
  y =  (/10, 100, 5000, 10, 9000, 70, 300, 10000, 600/)

  wks = gsn_open_wks("x11","logxy")   ; Open an X11 workstation.

  xyres = True
  xyres@tiXAxisString = "linear"
  xyres@tiYAxisString = "linear"

  xyplot = gsn_y(wks,y,xyres)  ; Create and draw the XY plot.

; Change the Y axis scale to be log and redraw the plot.
  xyres@trYLog        = True
  xyres@tiYAxisString = "log"
  xyres@xyComputeYMin = True   ; To keep from getting some warning msgs.

  xyplot = gsn_y(wks,y,xyres)  ; Create and draw the XY plot.

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

; Create some dummy data for the contour plot.
  N=25
  T = new((/N,N/),float)
  jspn = ispan(-N/2,N/2,1)^2
  ispn = ispan(-N/2,N/2,1)^2
  do i = 0, dimsizes(ispn)-1
      T(i,:) = ispn(i) + jspn
  end do
  T = 100.0 - sqrt(8^2 * T)

  wks = gsn_open_wks("x11","logcon")   ; Open an X11 workstation.

  cnres = True
  cnres@sfYCStartV    = 10
  cnres@sfYCEndV      = 1000
  cnres@tiXAxisString = "linear"   ; Label for X axis.
  cnres@tiYAxisString = "log"    ; Label for Y axis.
  cnres@trYLog        = True     ; Log scaling for Y axis

  contour = gsn_contour(wks,T,cnres)  ; Create and draw contour plot.

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

; Create some dummy data for the contour plot.
  N = 25
  T = new((/N,N/),float)
  jspn = ispan(-N/2,N/2,1)^2
  ispn = ispan(-N/2,N/2,1)^2
  do i = 0, dimsizes(ispn)-1
      T(i,:) = ispn(i) + jspn
  end do
  T = 100.0 - sqrt(8^2 * T)

  wks = gsn_open_wks("x11","logcon")

; Create some dummy data for the Y axis that is not regularly spaced.
  y = (/  10,   50,  100,  150,  250,  500,  750, 1000, 1100, 1300, 1500, \
        1750, 2000, 2200, 2400, 2600, 3000, 4000, 4500, 5000, 5100, 5500, \
        7000, 9000,10000/)

  cnres                       = True
  cnres@sfYArray              = y           ; Irregular Y axis
  cnres@gsnYAxisIrregular2Log = True        ; Force Y axis to be log.
  cnres@tiYAxisString         = "log"       ; Label for Y axis.
  cnres@tiXAxisString         = "linear"    ; Label for X axis.

  contour = gsn_contour(wks,T,cnres)  ; Create and draw contour plot.

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

; Create some data for the contour plot.
  data = generate_2d_array(10, 10, -19.69, 15.82, 0, (/129,129/))

  wks = gsn_open_wks("x11","fillcon")

  cnres                   = True
  cnres@cnFillOn          = True   ; Turn on contour level fill.
  cnres@cnMonoFillPattern = False  ; Indicate you want multiple fill patterns.
;
; Set cnFillPatterns and cnFillColors to various indexes representing
; fill patterns and colors.  A fill pattern index of "0" is solid fill.
; If you don't want any fill for a particular contour level, set it
; to "-1," which means "transparent."
;
  cnres@cnFillPatterns    = (/0, 2, 3, 0, 6, 8,10,-1, 9, 0,11,12,17,16/)
  cnres@cnFillColors      = (/6,10,14, 8, 4, 2, 9, 1,12, 3,20,13, 5, 7/)

  contour = gsn_csm_contour(wks,data,cnres)

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

; Create some dummy data for the contour/map plot.
  data = generate_2d_array(10, 10, -19.69, 15.82, 0, (/64,128/))

  wks = gsn_open_wks("x11","fillcon")

  res          = True
  res@sfXArray = fspan(-180,180,128)
  res@sfYArray = fspan( -90, 90, 64)

  plot = gsn_contour_map(wks,data,res)

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

; Create some dummy data for the contour/map plot.
  udata = generate_2d_array(10, 10, -19, 15, 0, (/32,64/))
  vdata = generate_2d_array(10, 10, -21, 17, 0, (/32,64/))

  wks = gsn_open_wks("x11","fillcon")

  res          = True
  res@tfDoNDCOverlay = True

  plot = gsn_vector_map(wks,udata,vdata,res)

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

  wks = gsn_open_wks("x11","mapres")

  res                   = True
  res@gsnMaximize       = True           ; Maximize plot in frame
  res@mpMinLonF         = -15.           ; Area to zoom in on.
  res@mpMaxLonF         =  15
  res@mpMinLatF         =  40.
  res@mpMaxLatF         =  70.

; Default "LowRes" database.
  map = gsn_csm_map(wks,res)

; "MediumRes" database.
  res@mpDataBaseVersion = "MediumRes" 
  map = gsn_csm_map(wks,res)

; "HighRes" database.
  res@mpDataBaseVersion = "HighRes" 
  map = gsn_csm_map(wks,res)

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

  cdf_file = addfile("$NCARG_ROOT/lib/ncarg/data/cdf/contour.cdf","r")

  Z    = cdf_file->Z(0,0,:,:)           ; geopotential height

  wks = gsn_open_wks("x11","spread_colors")   ; Open an X11 workstation.

  gsn_define_colormap(wks,"temp1")      ; Use a rainbow color map that
                                        ; has 63 colors and goes from
                                        ; gray to blue to red.
  res                       = True
  res@cnFillOn              = True   ; Turn on contour fill.
  res@lbLabelAutoStride     = True   ; Control labelbar label spacing.

  plot = gsn_csm_contour(wks,Z,res)  ; Draw a filled contour plot.
                                     ; are mostly blue.

  res@gsnSpreadColors = True         ; Choose colors across whole color map.
  plot = gsn_csm_contour(wks,Z,res)  ; Note that the contour colors now
                                     ; span from gray to blue to red.

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

  cdf_file = addfile("$NCARG_ROOT/lib/ncarg/data/cdf/contour.cdf","r")
  Z        = cdf_file->Z(0,0,:,:)           ; geopotential height

  wks = gsn_open_wks("x11","spread_colors")
  gsn_define_colormap(wks,"tbr_240-300")

  res                      = True
  res@gsnMaximize          = True
  res@cnFillOn             = True    ; Turn on contour fill
  res@gsnSpreadColors      = True    ; Spread the colors
  res@gsnSpreadColorStart  =  23     ; Start at 24th color
  res@gsnSpreadColorEnd    = 187     ; There are 201 colors
  res@lbLabelAutoStride    = True    ; Control labelbar labels

  plot = gsn_csm_contour(wks,Z,res)

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

;  Create a color map and an X11 workstation.
  cmap = (/ (/ 1., 1., 1. /),    \  ; 0 - White background.
            (/ 0., 0., 0. /),    \  ; 1 - Black foreground.
            (/ 1., 0., 0. /),    \  ; 2 - Red.
            (/ 0., 0., 1. /),    \  ; 3 - Blue.
            (/ 0., 1., 1. /),    \  ; 4 - Cyan.
            (/ 1., 0., 1. /)/)      ; 5 - Magenta.

  wks = gsn_open_wks("x11","wmlabs")
  gsn_define_colormap(wks,cmap)

;  Create a satellite view projection.
  mpres = True
  mpres@gsnFrame              = False        ; Don't advance the frame.
  mpres@gsnMaximize           = True         ; Maximize plot on page.
  mpres@mpOutlineBoundarySets = "National"
  mpres@mpGridLineColor       = 0
  mpres@mpCenterLatF          =   40.
  mpres@mpCenterLonF          = -105.
  map = gsn_map(wks,"Satellite",mpres)

;  Draw a stationary front.
  wmsetp("ezf",1)           ; Tell wmap we are using an existing map projection.
  wmsetp("lin",1.0)         ; Line width of front curve.
  wmsetp("fro","stationary"); Specify stationary front.
  wmsetp("cfc",3)           ; Use blue for the triangles.
  wmsetp("wfc",2)           ; Use red for the bumps.
  wmsetp("swi",0.04)        ; Increase the size of the bumps and triangles.
  xlat = (/  20.,   30.,   35.,   40.,  45. , 50./)   ; Latitudes.
  xlon = (/-195., -125., -115., -105., -95., -85./)   ; Longitudes.
  wmdrft(wks, xlat, xlon)   ; Draw front.

;  Draw a couple of High symbols.
  wmsetp("hib",4)              ; Cyan for background.
  wmsetp("his",1)              ; Black for shadow.
  wmsetp("hic",5)              ; Magenta for bounding circle.
  wmsetp("sht",0.02)           ; Increase size.
  xl = (/  50.,  50./)         ; Latitudes.
  yl = (/-105.,-145./)         ; Longitudes.
  wmlabs(wks, xl, yl, "HI")    ; Draw symbols.
  frame(wks)

load "$NCARG_ROOT/lib/ncarg/nclscripts/csm/gsn_code.ncl"
begin
    wks = gsn_open_wks("x11","test")

; Assumes '~' is the function code, and not the default ':'
    title = "This is a title~C~with a carriage return"
    txres = True
    txres@txFontHeightF = 0.03
    gsn_text_ndc(wks,title,0.5,0.5,txres)
end

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

begin
  wktype = "ps"
  wks  = gsn_open_wks (wktype, "thickness")
  cmap = (/"White","Black"/)
  gsn_define_colormap(wks,cmap)

;
;  Main title.
;
  txres = True
  txres@txFontHeightF = 0.04
  txres@txFont = 22
  gsn_text_ndc(wks,"Line thicknesses",0.5,0.95,txres)
  txres@txFontHeightF = 0.025
  gsn_text_ndc(wks, \
     "(results will vary depending on the output device)",0.5,0.88,txres)

;
;  Specify the sample line thicknesses.
;
  thicknesses = (/8.00, 4.00, 2.00, 1.00, 0.75, 0.50, 0.25, 0.00/)

;
;  Draw and label lines with the sample thicknesses.
;
  pres = True
  ytop = 0.78
  txres@txFontHeightF = 0.02
  txres@txJust = "CenterLeft"
  do i = 0,dimsizes(thicknesses)-1
    pres@gsLineThicknessF  = thicknesses(i)
    yh = ytop - 0.1*i
    gsn_text_ndc(wks,"Thickness = " + thicknesses(i),0.05,yh+0.025,txres)
    gsn_polyline_ndc(wks,(/0.05,0.95/),(/yh,yh/),pres)
  end do

  frame (wks)
end

  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/shea_util.ncl"

  data = generate_2d_array(10, 10, -19.69, 15.82, 0, (/129,129/))

  wks = gsn_open_wks("x11","max")

  plot = gsn_contour(wks,data,False)

  res             = True
  res@gsnFrame    = False
  plot = gsn_csm_contour(wks,data,res)

  infoTimeStamp(wks,0.02,"")

  frame(wks)

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