function set=nj_setcache(cacheDir, persistMinutes, scourEveryMinutes)
% nj_setcache : Enables caching for aggregating dataset
% Usage: set=nj_setcache(cacheDir, persistMinutes, scourEveryMinutes);
%   cacheDir - The full path name to the directory of the cache. Must be writeable.
%   persistMinutes - how old a file should be before deleting.
%   scourEveryMinutes - how often to run the scour process. If <= 0, don't scour.
%
% Example:  Cache every hour and delete stuff older than 30 days. 
%          nj_setcache('/home/rsignell/nj_cache', 60*24*30, 60));
%          nj_setcache('c:\rps\nj_cache', 60*24*30, 60));

% Sachin Bhate (skbhate@gri.msstate.edu)

import ucar.nc2.ncml.Aggregation;
import ucar.nc2.util.DiskCache2;

if nargin < 3 
    help nj_setcache
    return
end
% Create the Disk Cache objet
cache = DiskCache2(cacheDir, false, persistMinutes, scourEveryMinutes);
% Enable Aggregation caching
Aggregation.setPersistenceCache( cache );
%keep this object for furthur use.
set=cache;