dataset.addValue(1D, series1, category1);
dataset.addValue(5D, series1, category2);
dataset.addValue(4D, series1, category3);
dataset.addValue(8D, series1, category4);
dataset.addValue(7D, series1, category5);
dataset.addValue(3D, series2, category1);
dataset.addValue(4D, series2, category2);
dataset.addValue(3D, series2, category3);
dataset.addValue(5D, series2, category4);