clean(tempTable, ["time0", "mean_speed"])
tempTable = {
let twoDims = flights
.groupby({
time0: (d) => op.round(d.time),
distance0: (d) => op.round(d.distance / 100) * 100
})
.rollup({
mean_speed: (d) => op.round(op.mean(d.distance / d.time)),
count: (d) => op.count()
})
.orderby("time0", "distance0")
.reify();
//return twoDims;
let oneDim = flights
.groupby({
time0: (d) => op.round(d.time)
})
.rollup({
mean_speed: (d) => op.round(op.mean(d.distance / d.time))
})
.orderby("time0")
.reify();
return append(oneDim, twoDims);
}
tempTable.view({ limit: 13, offset: 400 })
// 准备缓存时，需要同时 groupby filter 的维度
// 查询缓存，需要先筛选出缓存数据，聚合的时候，count => sum
query0 = tempTable
.filter((d) => d.time0 !== undefined && d.distance0 !== undefined)
.filter((d) => d.distance0 === 400)
.groupby("time0")
.rollup({ count: (d) => op.sum(d.count) })
.view(13)
// filter distance = 400，groupBy time，count
expectResult0 = flights
.filter((d) => op.round(d.distance / 100) * 100 === 400)
.groupby({ time0: (d) => op.round(d.time) })
.rollup({ count: (d) => op.count() })
.orderby("time0")
.view(13)
// 查询缓存，需要先筛选出缓存数据，获取聚合的时候，只能 select
query1 = tempTable
.filter((d) => d.time0 !== undefined && d.distance0 !== undefined)
.filter((d) => d.distance0 === 400 || d.distance0 === 500) // 这里出问题了！
.select("time0", "mean_speed")
.view(13)
expectResult1 = flights
.filter(
(d) =>
op.round(d.distance / 100) * 100 === 400 ||
op.round(d.distance / 100) * 100 === 500
)
.groupby({
time0: (d) => op.round(d.time)
})
.rollup({
mean_speed: (d) => op.round(op.mean(d.distance / d.time))
})
.orderby("time0")
.view(13)
flights = aq.loadArrow(
"https://vega.github.io/vega-datasets/data/flights-200k.arrow"
) // 测试数据
flights.view(5)
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