Hi John,
thanks for your quick response.
If I'm going to use a single index (to save time), it can't be named
<filename>.gbx, because I want to use one index file for multiple grib
files, so I can save the time of making an index each time I read a
similar file. I'm assuming the index is a property of the particular
fields that are in a file, but not values in the field. If the indices
differ depending on the data in the files, then this obviously won't work.
If it can work, then I'd like to specify a specific index file, like
'RR.gbx' to work for all the RR (Rapid Refresh model, actually) files.
By the way, what is "TDS"?
-Bill
On 2/9/2009 4:14 PM, John Caron wrote:
Hi Bill:
If you create the indexes externally, the library will use them (they better be
right!). They must
be named <filename>.gbx, and placed in the DiskCache.setRootDirectory().
For Grib files, I just noticed that theres some more stuff you have to do. In
4.0, the policy is set
seperately from DiskCache. So you need to call
GribServiceProvider.setIndexAlwaysInCache( true); // force use the cache for
grib index
You probably also want to set
GribServiceProvider.setIndexExtendMode( IndexExtendMode.none); // never write
an index
GribServiceProvider.setIndexSyncMode( IndexExtendMode.none); // never sync
the index
this means that the index will never be created by the library, which is needed
if you are in a
multi-threaded situation like on a server. This is what the TDS does.
Ill add this to the docs.
Id like to hear what is your use case that might require this?
Bill Moninger wrote:
Hello,
I understand that I can use
DiskCache.setRootDirectory("grib_data");
to set a directory where grib index files will be stored. This allows me
to read and process grib files from a read-only directory.
However, I recall reading that it is possible to use a pre-defined index
file to save the time involved in generating an index file. In spite of
a lot of looking I haven't (re)found the documentation that tells me how
to do it.
My question: how do I tell the netcdf4 reader to use a specified index
file (and one that is in a different directory than the data files)?
-Bill
--
William R. Moninger http://www-frd.fsl.noaa.gov/~moninger/
NOAA / Earth Systems Research Laboratory / Global Systems Division
325 Broadway, R/GSD1 voice: 303-497-6435
Boulder, CO 80305 fax: 303-497-3329
