codes.py 文件源码

def Zcorrections(self):
        '''Qubits on which to apply Z operator to fix the X stabilizer.'''
        L = self.L
        graph = self.Xwgraph()
        matches = {tuple(sorted(_)) for _ in
                   nx.max_weight_matching(graph, maxcardinality=True).items()}
        qubits = set()
        for (y1, x1), (y2, x2) in matches:
            ym, yM = 2*min(y1, y2), 2*max(y1, y2)
            if yM-ym > L:
                ym, yM = yM, ym+2*L
                horizontal = yM if (x2-x1)*(y2-y1)<0 else ym
            else:
                horizontal = ym if (x2-x1)*(y2-y1)<0 else yM
            xm, xM = min(x1, x2), max(x1, x2)
            if xM-xm > L/2:
                xm, xM = xM, xm+L
                vertical = xM
            else:
                vertical = xm
            qubits.update((horizontal%(2*L), _%L) for _ in range(xm, xM))
            qubits.update(((_+1)%(2*L), vertical%L) for _ in range(ym, yM, 2))
        return matches, qubits