def __getstate__(self):
dict = Mesh2D.__getstate__(self)
dict['epsilon'] = self.epsilon
dict['actualDomainHeight'] = self.actualDomainHeight
dict['actualFineRegionHeight'] = self.actualFineRegionHeight
dict['cellSize'] = self.cellSize
dict['fineMesh'] = self.fineMesh
dict['faceVertexIDs'] = self.faceVertexIDs.filled()
return dict
