// set parent
Node(ModelReader reader) throws IOException {
parent_ = reader.readInt();
cleft_ = reader.readInt();
cright_ = reader.readInt();
sindex_ = reader.readInt();
if (is_leaf()) {
leaf_value = reader.readFloat();
split_cond = Float.NaN;
} else {
split_cond = reader.readFloat();
leaf_value = Float.NaN;
}
}
RTreeNodeStat(ModelReader reader) throws IOException {
loss_chg = reader.readFloat();
sum_hess = reader.readFloat();
base_weight = reader.readFloat();
leaf_child_cnt = reader.readInt();
}