from ATK.TwoProbe import *

# Reopen old two-probe configuration
vnl_file = VNLFile("lih2li.vnl")
atomic_configuration = vnl_file.readAtomicConfigurations()["lih2li"]

# Restore results from previous calculations
bias0V = restoreSelfConsistentCalculation('lih2li-bias-0.0.nc')
bias1V = restoreSelfConsistentCalculation('lih2li-bias-1.0.nc')

# Calculate effective potentials ...
pot_0V = calculateEffectivePotential(bias0V)
pot_1V = calculateEffectivePotential(bias1V)

# ... and find the difference = the voltage drop
potential_drop = pot_1V - pot_0V

# Store result in a new VNL file
vnl_file = VNLFile("lih2li-voltdrop.vnl")
vnl_file.addToSample(atomic_configuration,'lih2li-voltdrop')
vnl_file.addToSample(potential_drop,'lih2li-voltdrop')