data = {
const rand = d3.randomNormal()
while(true) {
let n = (Math.random() * 300 + 750)|0
const x = d3.range(n).map(n => rand()).sort(d3.ascending)
if (Math.random() < 0.99) {
const scale = Math.random() + 1;
const q = Math.random() / 2;
x.forEach((val,i) => {if (i>n*(1-q) && Math.random()<0.7) x[i] = val*scale});
x.forEach((val,i) => {if (i<n*q && Math.random()<0.7) x[i] = (x[i]+x[i+1])/2});
}
yield x
await Promises.tick(2000)
}
}