public Canvas canvas() {
        Canvas canvas = new Canvas(getLowerBound(), getUpperBound());
        canvas.add(this);
        if (name != null) {
            canvas.setTitle(name);
        }
        return canvas;
    }
@Test
    public void testIris() throws Exception {
        System.out.println("Iris");

        var canvas = ScatterPlot.of(iris, "sepallength", "sepalwidth", "petallength", "class", '*').canvas();
        canvas.setAxisLabels("sepallength", "sepalwidth", "petallength");
        canvas.window();
    }