R help - Nov 2010 - Problem downloading and opening netcdf file

I am trying to download and open an on-line netcdf file. 

I'm using Windows XP and R 2.11.1

Here's my script

  library(ncdf)
  link <-
"http://ibis.grdl.noaa.gov/SAT/SeaLevelRise/slr/slr_sla_gbl_free_all_66.nc"
  dest <-  "C:/temp/slr_sla_gbl_free_all_66.nc"
  download.file(url=link,destfile=dest) 
  nc1 <- open.ncdf(dest)

The file appears in my C:/temp directory, however I can not open() it, I get
this error message:
>   nc1 <- open.ncdf(dest)
Error in open.ncdf(dest) : 
  Error in open.ncdf trying to open file
C:/temp/slr_sla_gbl_free_all_66.nc
> 
I can manually download and save the netcdf file and then open it. I'd like
to be able to automate the download and open process within my script.

Any suggestions?



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On Wed, Nov 17, 2010 at 2:54 PM, D Kelly O'Day <koday at
processtrends.com> wrote:
>
> I am trying to download and open an on-line netcdf file.
>
> I'm using Windows XP and R 2.11.1
>
> Here's my script
>
> ?library(ncdf)
> ?link <-
>
"http://ibis.grdl.noaa.gov/SAT/SeaLevelRise/slr/slr_sla_gbl_free_all_66.nc"
> ?dest <- ?"C:/temp/slr_sla_gbl_free_all_66.nc"
> ?download.file(url=link,destfile=dest)
> ?nc1 <- open.ncdf(dest)
>
> The file appears in my C:/temp directory, however I can not open() it, I
get
> this error message:
>
>> ? nc1 <- open.ncdf(dest)
> Error in open.ncdf(dest) :
> ?Error in open.ncdf trying to open file C:/temp/slr_sla_gbl_free_all_66.nc
>>
>
> I can manually download and save the netcdf file and then open it. I'd
like
> to be able to automate the download and open process within my script.
 Works for me. When you get the file with download.file is it
identical to when you download it from a web browser? I can only think
its getting corrupted, or perhaps your download.file isn't going
through a proxy or something and you're actually saving a proxy error
message file.

 Check the length of the saved file: file.info(dest) should help -
check the 'size' is what you expect. I get 17004 for that example.

Barry