Looking at the plotband.f90 code, jumps are allowed: IF (dxmod > 5*dxmod_save) THEN ! ! A big jump in dxmod is a sign that the point k(:,n) and k(:,n-1) ! are quite distant and belong to two different lines. We put them on ! the same point in the graph ! kx(n)=kx(n-1) Cheers, Vahid