module.exports = { config: { type: 'polarArea', data: { labels: [0, 1, 2, 3, 4, 5], datasets: [ { // option in element (fallback) data: [0, 2, 4, null, 6, 8], } ] }, options: { elements: { arc: { backgroundColor: function(ctx) { var value = ctx.dataset.data[ctx.dataIndex] || 0; return value > 8 ? '#ff0000' : value > 6 ? '#00ff00' : value > 2 ? '#0000ff' : '#ff00ff'; } } }, scales: { r: { display: false } } } }, options: { canvas: { height: 256, width: 512 } } };