Detect a single core-periphery pair.
	
		Parameters
		----------
		G : NetworkX graph object
		
		Examples
		--------
		>>> import networkx as nx
		>>> import cpalgorithm as cpa
		>>> G = nx.karate_club_graph()  # load the karate club network. 
		>>> lrc = cp.LowRankCore()
		>>> lrc.detect(G)

def detect(self, G):
		"""Detect a single core-periphery pair.
	
		Parameters
		----------
		G : NetworkX graph object
		
		Examples
		--------
		>>> import networkx as nx
		>>> import cpalgorithm as cpa
		>>> G = nx.karate_club_graph()  # load the karate club network. 
		>>> lrc = cp.LowRankCore()
		>>> lrc.detect(G)

		"""
		
		self.c_, self.x_ = self._low_rank_core(G)
		
		self.Q_ = self._score(G, self.c_, self.x_) 
		self.qs_ = self.Q_