octave:17> [EE,psi, DeltaE] = eigenstates(@v1doubledip, 5.4, 1e-12, 1.2, 1000); Options for LSODE include: keyword value ------- ----- absolute tolerance 2.22e-16 relative tolerance 1e-12 integration method non-stiff initial step size -1 maximum order -1 maximum step size -1 minimum step size 0 step limit 100000 predict_N_eigenvals = 4.0745 n = 1 eigenvalue = -6.75035426995796 Eigenvalue_uncertainty = -6.7504e-12 n = 2 eigenvalue = -6.74239989235951 %%% About 0.1% higher than ground state %%% Eigenvalue_uncertainty = -6.7424e-12 n = 3 eigenvalue = -0.992178434655953 Eigenvalue_uncertainty = -9.9218e-13 n = 4 eigenvalue = -0.733040203015612 Eigenvalue_uncertainty = -7.3304e-13