}
public void writeToDir(File od, String tag)throws Exception{
GenomicRegionsBuilder gbr= new GenomicRegionsModifier(gbtr).getExtendedRegions(side, side);
GenomicRegionsComparator gc= new GenomicRegionsComparator(gbpeak, gbr);
File ofa= new File(od+"/asso-"+side+"_"+ tag+".bed");
File ofn= new File(od+"/asso-not-"+side+"_"+ tag+".bed");
new BedExporter( gc.getIntersection() ).writeToFile(ofa);
new BedExporter( gc.getNonIntersection() ).writeToFile(ofn);
}