public function isDescendantOf($subj)
    {
        return ($this->lft > $subj->lft) && ($this->rgt < $subj->rgt) && ($this->root === $subj->root);
    }
public function isDescendantOf($subj)
    {
        return ($this->lft > $subj->lft) && ($this->rgt < $subj->rgt) && ($this->root === $subj->root);
    }
public function isDescendantOf ( $ subj ) { return ( $ this -> lft > $ subj -> lft ) && ( $ this -> rgt < $ subj -> rgt ) && ( $ this -> root === $ subj -> root ) ; }
Determines if node is descendant of subject node.

@param TreeModel $subj the subject node

@return bool whether the node is descendant of subject node
Determines if node is descendant of subject node .