Hi all,

Thank you for addressing my previous query.

I am trying to plot first few incoming transverse waveguide modes on lead 0. I am wondering whether it is possible to plot all incoming modes on Lead 0. kwant.physics.modes gives me PropagatingModes and Stabilized modes but I want to select just first few modes of incoming flux. 
Here is the sample code of my system

import kwant                     
import numpy as np               
from matplotlib import pyplot
from numpy import sqrt
from math import *


#======================================================================
# Define the shape -------------------
#======================================================================
def shape(pos):
    x, y = pos
    return (np.abs(2.0*x)<=L)&(np.abs(y)<W1/2.0)
#----------------------------------------------------------------------

a      = 1;     
t      = 1;    
E0L    = 0*t   
L      = 10;  # Length of the
W1   = 30;  # Width on the left

# Define geometry
--------------------------------------------------------------------------
sys0 = kwant.Builder()
lat  = kwant.lattice.square(a)
#--------------------------------------------------------------------------------------------
# Define onsite energies and couplings
----------------------------------------------------
sys0[lat.shape(wv_shape,(0,0))] = E0     # To make all sites the same
sys0[lat.neighbors()]           = t
#--------------------------------------------------------------------------------------------

# Left lead
----------------------------------------------------------------------------------
left_lead = kwant.Builder(kwant.TranslationalSymmetry([-1,0]))  
left_lead[(lat(0,y) for y in range(int(-W1/2+1),int(W1/2)))] = E0L
left_lead[lat.neighbors()] = t                                                             
sys0.attach_lead(left_lead);
#--------------------------------------------------------------------------------------------
# Right lead
---------------------------------------------------------------------------------
right_lead = kwant.Builder(kwant.TranslationalSymmetry([1,0])) 
right_lead[(lat(0,y) for y in range(int(-W1/2+1),int(W1/2)))] = E0L
right_lead[lat.neighbors()] = t                                  
sys0.attach_lead(right_lead);
#---------------------------------------------------------------------------------------------
sys = sys0.finalized()
kwant.plot(sys);                                        


def plot_conductance(sys, energies):

    data = []
    for energy in energies:
        smatrix = kwant.smatrix(sys, energy)
        data.append(smatrix.transmission(2, 0)+smatrix.transmission(1,2) )
        #transmission from left 2 leads to right lead

    pyplot.figure()
    pyplot.plot(energies, data)
    pyplot.xlabel("energy [t]")
    pyplot.ylabel("conductance [e^2/h]")
    pyplot.show()
energies=[-3+i*0.02 for i in range(100)]
plot_conductance(sys,energies)