Re: fatal error

Wei,

The error is telling you what's wrong. It's saying that you are
trying to access "v" as if it were a file pointer.
This means you are trying to do something like this:

      x = v->x

"v" is not a file pointer, but "a" is. A file pointer is what's
returned when you call "addfile".

You need to replace your "v->" with "a->".

For example:

hyam = v->hyam

should be:

hyam = a->hyam

--Mary

On Mar 29, 2010, at 4:40 AM, wei huang wrote:

> Hello NCL talk,
> Could anyone fix the problem given below:
> fatal:(v) does not reference a file
> fatal:Execute: Error occurred at or near line 25 in file stf1.ncl
>
> And also the code is attached:
> Thanks
> wei
>
> 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"
> begin
> ;************************************************
> ; read in netCDF file
> ;************************************************
> a = addfile("vwnd.1999.nc","r")
> ;a1 = addfile("pres.sfc.1999.nc","r")
> ;************************************************
> ; read in data required for calculation
> ;************************************************
> v = short2flt(a->vwnd(0,:,:,:))
> ;ps = short2flt(a1->pres(0,:,:))
> printVarSummary(v)
>
> ; vinth2p requires the lev_p to be expressed in mb [hPa]
> lev_p = (/300,500,850,1000 /)
> lev_p!0 = "lev_p" ; variable/dim name
> lev_p&lev_p = lev_p ; create coordinate variable
> lev_p@long_name = "pressure" ; attach some attributes
> lev_p@units = "hPa"
> lev_p@positive = "down"
>
> hyam = v->hyam ; read from file
> hybm = v->hybm
> P0mb = v->P0*0.01
> ps = v->ps ; these are in Pa
> v = v->V
> ; convert to pressure levels
> vp = vinth2p(v,hyam,hybm,lev_p,ps,intyp,P0mb,1,False)
> ; calculate zonal meridional streamfunction
> psi = zonal_mpsi_Wrap(vp,lat,lev_p*100.,ps)
> wks = gsn_open_wks("x11","h_lat") ; open a ps file
> plot= gsn_csm_pres_hgt(wks,psi,False) ; create plot
> end
> ===================
> Variable: v
> Type: float
> Total Size: 714816 bytes
> 178704 values
> Number of Dimensions: 3
> Dimensions and sizes: [level | 17] x [lat | 73] x [lon | 144]
> Coordinates:
> level: [1000..10]
> lat: [90..-90]
> lon: [ 0..357.5]
> Number Of Attributes: 16
> time : 17549208
> long_name : mean Daily V wind
> valid_range : ( -125, 160 )
> actual_range : ( -81.77499, 82.47501 )
> units : m/s
> precision : 2
> least_significant_digit : 1
> GRIB_id : 34
> GRIB_name : VGRD
> var_desc : v-wind
> V
> dataset : NCEP Reanalysis Daily Averages
> level_desc : Multiple levels
> F
> statistic : Mean
> M
> parent_stat : Individual Obs
> I
> _FillValue : 32766
> missing_value : 32766
> _______________________________________________
> ncl-talk mailing list
> List instructions, subscriber options, unsubscribe:
> http://mailman.ucar.edu/mailman/listinfo/ncl-talk

_______________________________________________
ncl-talk mailing list
List instructions, subscriber options, unsubscribe:
http://mailman.ucar.edu/mailman/listinfo/ncl-talk
Received on Mon Mar 29 08:18:58 2010