Re: finding nearest point and 4 nearest points

I believe this would find the closest gridcells within 5km of stn_lat
and stn_lon:

   lon = file2->XLONG(0,:,:)
   lat = file2->XLAT(0,:,:)
   dist = gc_latlon(stn_lat,stn_lon,lat,lon,2,4)
   ndist = dimsizes(dist)
   dist1d = ndtooned(dist)
   tmp = dimsizes(ind(dist1d.le.5.0))
   if (tmp.lt.2) then
      print("No gridcells found within 5km...")
      exit
   else
      distidx = ind_resolve(ind(dist1d.le.5.0),ndist) ; within 5km
      ndistidx = dimsizes(distidx)
   end if
   delete(tmp)

Scott

On 5/3/12 5:36 AM, Dorita Rostkier-Edelstein wrote:
> Hi folks,
>
> Does anyone have a script to find the closest and the 4 closest points
> to a given lat/lon, the nc file has the WRF XLAT, XLONG (pasted below).
>
> Thanks.
>
> Dorita
>
> netcdf wrf_static {
> dimensions:
> Time = UNLIMITED ; // (1 currently)
> south_north = 171 ;
> west_east = 96 ;
> variables:
> float HGT(Time, south_north, west_east) ;
> HGT:FieldType = 104 ;
> HGT:MemoryOrder = "XY " ;
> HGT:description = "Terrain Height" ;
> HGT:units = "m" ;
> HGT:stagger = "" ;
> HGT:coordinates = "XLONG XLAT" ;
> float XLAND(Time, south_north, west_east) ;
> XLAND:FieldType = 104 ;
> XLAND:MemoryOrder = "XY " ;
> XLAND:description = "LAND MASK (1 FOR LAND, 2 FOR WATER)" ;
> XLAND:units = "" ;
> XLAND:stagger = "" ;
> XLAND:coordinates = "XLONG XLAT" ;
> float XLAT(Time, south_north, west_east) ;
> XLAT:FieldType = 104 ;
> XLAT:MemoryOrder = "XY " ;
> XLAT:description = "LATITUDE, SOUTH IS NEGATIVE" ;
> XLAT:units = "degree_north" ;
> XLAT:stagger = "" ;
> float XLONG(Time, south_north, west_east) ;
> XLONG:FieldType = 104 ;
> XLONG:MemoryOrder = "XY " ;
> XLONG:description = "LONGITUDE, WEST IS NEGATIVE" ;
> XLONG:units = "degree_east" ;
> XLONG:stagger = "" ;
>
>
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Received on Thu May 3 08:12:20 2012