throw new IllegalStateException(); int partWant = vip.partnoSA.findIdx(partno); // which partition ? index into PartitionCollectionImmutable.partitions[]. variable doesnt have to exist in all partitions if (partWant < 0 || partWant >= vip.nparts) { if (Grib.debugRead) System.out.printf(" cant find partition=%d in vip=%s%n", partno, vip);