public void plotPropagationCurves() {
        double[] eRange = getEnergyRange();
        PlotFrame frame = new PlotFrame("Energy", "Propagation", "QW Propagation Curves");
        for (int i = 1; i < intervals.size() - 1; i++) {
            if (intervals.get(i).getY() < intervals.get(i - 1).getY() && intervals.get(i).getY() < intervals.get(i + 1).getY()) {
                for (double e : eRange) {
                    frame.append(i, Utils.erg2ev(e), getPropagationValueLog(i, e));
                }
                frame.setMarkerShape(i, 0);
            }
        }
        frame.setSize(600, 600);
        frame.setConnected(true);
        frame.setVisible(true);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    }