[ncl-talk] Most data disappeared after mask data with shapefile according to the example on the website.

[grace]

Hi:
  All,I am trying to mask data with shapefile according  to the example shapefiles_14_mask.ncl on the NCL website.
But most data disappeared after mask.
The right plot is the plot after mask,the left one is the original plot.



This is my script:
;   Example script to produce precip plots with satationdata,


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"/public/home/huanglei/map/shapefile_mask_data.ncl"
begin
 station_file ="/public/home/huanglei/data/20160724/stationdata_20160724.txt" 
 data  = asciiread(station_file,-1,"string")
 num_att = numAsciiCol(station_file)  ;return the number of columns of the stationfile
 print(num_att)


  lon_station1   = stringtofloat(str_get_field(data(0:1889),2," "))
  lat_station1  = stringtofloat(str_get_field(data(0:1889),3," "))
  obs_precip1 = stringtofloat(str_get_field(data(0:1889),4," "))




  olon = fspan(105.5,110.9,100)
  olat = fspan(31.5,35.8,100)


  olon!0          = "lon"
  olon at long_name  = "lon"
  olon at units      = "degrees-east"
  olon&lon        = olon
  olat!0          = "lat"
  olat at long_name  = "lat"
  olat at units      = "degrees_north"
  olat&lat        = olat
  print("......")
  obs_precip1 at _FillValue = -999.000000
 rscan = (/0.5,0.2,0.1/)   
  griddata = obj_anal_ic_deprecated(lon_station1,lat_station1,obs_precip1,olon,olat,rscan,False)
;;;;;;;;;;;;;;;;;;;;;;mask data with shapfile;;;;;;;;;;;;;;;;;;;
  shp_filename = "/public/home/huanglei/map/shaanxi_city_l.shp"
  final= shapefile_mask_data(griddata,shp_filename,True)
 ; exit
  wks = gsn_open_wks ("pdf","rain20160724")  
    
  res                         = True            
  res at gsnMaximize             = True
  res at gsnDraw                 = False
  res at gsnFrame                = False


;>--------------------------------------------<
;            set for the map 
;>--------------------------------------------<
  res at mpMinLatF               = 31.5                        
  res at mpMaxLatF               = 35.8
  res at mpMinLonF               = 105.5
  res at mpMaxLonF               = 110.9
  res at tmXBMode                = "Explicit"   
  res at tmXBValues              = (/106,107,108,109,110/) 
  res at tmXBLabels              = (/"106~S~o~N~E","107~S~o~N~E","108~S~o~N~E","109~S~o~N~E","110~S~o~N~E"/)   
 ; res at tmXBMinorValues         = fspan(97,109,30) 
 ; res at tmXBMinorOn             = True  
  
  res at tmYLMode                = "Explicit"    
  res at tmYLValues              = (/32,33,34,35/) 
  res at tmYLLabels              = (/"32~S~o~N~N","33~S~o~N~N","34~S~o~N~N","35~S~o~N~N"/)   
  ;res at tmYLMinorValues         = fspan(26,36,20) 
  ;res at tmYLMinorOn             = True  


  res at mpFillOn                = True
  res at mpOutlineOn             = False    
  res at cnFillDrawOrder         = "PreDraw"
  res at mpDataBaseVersion       = "MediumRes"
  res at mpDataSetName           = "Earth..4"
  res at mpAreaMaskingOn         = True
  res at mpLandFillColor         = "white"
  res at mpInlandWaterFillColor  = "white"
  res at mpOceanFillColor        = "white"
  res at mpOutlineBoundarySets   = "NoBoundaries"


;>--------------------------------------------<
; set for the plot
;>--------------------------------------------<


  res at cnFillOn                = True               
  res at cnLinesOn               = False             
 ; res at cnLevelSpacingF         = 0.2             
  res at gsnSpreadColors         = True         
  res at lbLabelAutoStride       = True
  res at gsnAddCyclic            = False   
            
  res at cnLevelSelectionMode = "ExplicitLevels"
  res at cnLevels             = (/ .1, .4, .8, 1.6, 3.2, 6.4, \
                                        12.8, 25.6, 51.2,100/)
  res at cnFillColors         = (/"White","DarkOliveGreen1", \
                                        "DarkOliveGreen3","Chartreuse", \
                                        "Chartreuse3","Green","ForestGreen", \
                                        "Yellow","Orange","Red","Violet"/)
  map = gsn_csm_contour_map(wks,final,res) 


;>------------------------------------------------------------<
;                      add  map
;>------------------------------------------------------------<


 shp_name1    = "/public/home/huanglei/map/xian.shp"
 shp_name2    = "/public/home/huanglei/map/shaanxi_city_l.shp"
  lnres                  = True
  lnres at gsLineColor      = "gray25"
  lnres at gsLineThicknessF = 1.5   


 id = gsn_add_shapefile_polylines(wks,map,shp_name1,lnres)
 id2= gsn_add_shapefile_polylines(wks,map,shp_name2,lnres)
;>------------------------------------------------------------<
  
 ; station             = asciiread("/public/home/huanglei/data/prcdata.txt",(/160,3/),"float")  
  
  res2                 = True                       
  res2 at gsMarkerIndex   = 16                       
  res2 at gsMarkerSizeF   = 6.               
  res2 at gsMarkerColor   = "Violet"                   
  res2 at tfPolyDrawOrder = "PostDraw"  
  res2 at cnFillDrawOrder = "PostDraw"  
   ;
 plots1=gsn_add_polymarker(wks,map,108.9373,34.2158,res2)
 plots2=gsn_add_polymarker(wks,map,108.9133,34.2303,res2)
 plots3=gsn_add_polymarker(wks,map,108.8908,34.1953,res2)


 ; plots=gsn_add_polymarker(wks,map,station(:,1),station(:,2),res2)
   delete(res2)  
  draw(map)
  frame(wks)
  end 

 How can I slove the problem?
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://mailman.ucar.edu/pipermail/ncl-talk/attachments/20160810/64053191/attachment.html 
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/jpeg
Size: 206822 bytes
Desc: not available
Url : http://mailman.ucar.edu/pipermail/ncl-talk/attachments/20160810/64053191/attachment.jpe