Re: Deleted attribute reappears

Thanks, Mary. I'll give it a try. I don't know why my original email got
sent 3 times! Sorry!

-Bridget

On Thu, Jun 30, 2011 at 3:53 PM, Mary Haley <haley@ucar.edu> wrote:

> Bridget,
>
> I'm not positive about this, but if "dat" already has a time coordinate
> array attached to it, and that "time" coordinate array has a "description"
> attribute, then it will be retained, even when you do:
>
> dat&time = t2
>
> Therefore, inside your loop, you might need to delete the description
> attribute from the time coordinate array attached to "dat" directly:
>
> dat = fin->data(ii,:,:)
>
> . . .
> delete(dat&times@description)
>
> --Mary
>
> On Jun 30, 2011, at 4:23 PM, Bridget Thrasher wrote:
>
> I've got a file with 32 years of daily data that I'm breaking into files of
> individual years. The time variable in the original file has an incorrect
> "description" attribute that I am deleting. But when I write the new yearly
> file, the attribute reappears! I can figure out a work around, but I'd like
> to understand what I'm doing wrong. I'm running 5.2.0. Here is a code
> snippet followed by the screen output:
>
> CODE:
>
> times = fin->day
> delete_VarAtts(times,"description")
> printVarSummary(times)
> t = ut_calendar(times,-5)
> strs = str_split(fin,"_")
> vname = strs(0)
> do y = 1979,2010
> ii = ind(t(:,0).eq.y)
> fname = strs(0)+"_"+y+".nc"
> fout = addfile(fname,"c")
> t2 = times(ii)
> printVarSummary(t2)
> dat = fin->data(ii,:,:)
> dat!0 = "time"
> dat!1 = "lat"
> dat!2 = "lon"
> dat&time = t2
> fout->$vname$ = dat
> delete(ii)
> delete(dat)
> delete(t2)
> system("ncdump -h "+fname)
> end do
>
>
> OUTPUT:
>
> Variable: times
> Type: float
> Total Size: 46752 bytes
> 11688 values
> Number of Dimensions: 1
> Dimensions and sizes: [day | 11688]
> Coordinates:
> day: [722816..734503]
> Number Of Attributes: 2
> units : days since 0001-01-01
> calendar : gregorian
>
>
> Variable: t2
> Type: float
> Total Size: 1460 bytes
> 365 values
> Number of Dimensions: 1
> Dimensions and sizes: [day | 365]
> Coordinates:
> day: [722816..723180]
> Number Of Attributes: 2
> calendar : gregorian
> units : days since 0001-01-01
>
> netcdf pr_1979 {
> dimensions:
> time = 365 ;
> lat = 200 ;
> lon = 464 ;
> variables:
> float pr(time, lat, lon) ;
> pr:units = "mm" ;
> pr:description = "Daily Accumulated Precipitation" ;
> pr:_FillValue = -9999.f ;
> float time(time) ;
> time:units = "days since 0001-01-01" ;
> time:calendar = "gregorian" ;
> *time:description = "days since 1900-01-01" ;*
> float lat(lat) ;
> lat:units = "degrees_north" ;
> lat:description = "Latitude of the center of the grid cell" ;
> float lon(lon) ;
> }
>
>
> Any insight?
>
> --
> Bridget Thrasher, PhD
> Independent Contractor, Research Scientist
>
>
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>

-- 
Bridget Thrasher, PhD
Independent Contractor, Research Scientist