// PREpend all of 'nc' onto the current NewChunk. Kill nc.
public void addr(NewChunk nc) {
long[] tmpl = _ls;
_ls = nc._ls;
nc._ls = tmpl;
int[] tmpi = _xs;
_xs = nc._xs;
nc._xs = tmpi;
tmpi = _id;
_id = nc._id;
nc._id = tmpi;
double[] tmpd = _ds;
_ds = nc._ds;
nc._ds = tmpd;
int tmp = _sparseLen;
_sparseLen = nc._sparseLen;
nc._sparseLen = tmp;
tmp = _len;
_len = nc._len;
nc._len = tmp;
add(nc);
}
