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
