           }

                option = {
                    tooltip: {},
                    visualMap: {
                        type: 'piecewise',
                        inverse: true,
                        top: 10,
                        left: 10,
                        pieces: [{
                            value: 0, color: COLORS[0]
                        }, {
                            value: 1, color: COLORS[1]
                        }, {
                            value: 2, color: COLORS[2