def X(self):
"""Return X vector (of unknowns) for MNA"""
self._analyse()
V = ['V_' + node for node in self.node_list[1:]]
I = ['I_' + branch for branch in self.unknown_branch_currents]
return Vector(V + I)
def ZV(self):
"""Return Z vector for MNA"""
self._analyse()
return Vector(self._Z)