Local hydrodynamic stability problem

I am trying to solve for local hydrodynamic stability for plane poiseuille flow (incompressible and viscous)
I tried using meshL to create 1d domain but the A branch of the eigenvalue spectrum is not matching with the standard result.
Can you help with the solver and tgv value that i should use?

Also is there a way to plot eigenvectors in matlab after finding them using eigs? the results given by the Eigenvalue function is not correct.