dataset.addValue(1.0, "Series 1", "Category 1");
dataset.addValue(5.0, "Series 1", "Category 2");
dataset.addValue(4.0, "Series 1", "Category 3");
dataset.addValue(3.0, "Series 1", "Category 4");
dataset.addValue(6.0, "Series 1", "Category 5");
dataset.addValue(4.0, "Series 1", "Category 6");
dataset.addValue(3.0, "Series 1", "Category 7");
dataset.addValue(5.0, "Series 2", "Category 1");
dataset.addValue(7.0, "Series 2", "Category 2");
dataset.addValue(8.0, "Series 2", "Category 3");
dataset.addValue(6.0, "Series 2", "Category 4");