{
const svg = DOM.svg(width, height)
const sel = d3.select(svg)
const join = sel.selectAll('g.grid')
.data(gridData)
.enter().append('g')
.attr('class', 'grid')
.attr('transform', (d, i) => {
return `translate(${xScale(d.x)}, ${yScale(d.y)})`
})
sel.selectAll('g.grid').each(function(d,i) {
const cell = d3.select(this).append('g')
cell.append('circle').attr('r', 20).attr('fill', 'red')
})
return svg
}