def update(self, v, c_id):
        c_ind = self.child_id2ind[c_id]
        self.child_vals[c_ind] = v
        self.child_expands[c_ind] += 1
updates this node's value based on the updated value for the child c_id
dataset/ETHPy150Open rll/lfd/lfd/mmqe/search.py/SearchNode.update