The stack layout allows us to stack regions in a chart, which is useful for things such as stacked area charts and what have you. It's in the d3-shape package.
Go back to main.js and comment out the last example and add the following:
westerosChart.init('stack',
'data/GoT-deaths-by-season.json', false);We add another option to this because we're going to create two charts from this example. This time we're using our deaths-by-season dataset.
Inchapter7/index.js add the following to the bottom of the file:
westerosChart.stack = function Stack({ data }, isStream = false) {
const episodesPerSeason = 10;
const totalSeasons = 6;
// Create a nest containing deaths per episode
const seasons = d3.nest()
.key(d => d.death.episode)
.key(d => d.death.season)
.entries(data.filter(d => !d.death.isFlashback))
.map(v => {
return d3.range(1, totalSeasons + 1)
.reduce((item, episodeNumber) => {
const deaths = v.values.filter...