anki/ts/src/stats/intervals.ts
2020-06-29 15:48:01 +10:00

99 lines
2.8 KiB
TypeScript

// Copyright: Ankitects Pty Ltd and contributors
// License: GNU AGPL, version 3 or later; http://www.gnu.org/licenses/agpl.html
/* eslint
@typescript-eslint/no-non-null-assertion: "off",
@typescript-eslint/no-explicit-any: "off",
*/
import pb from "../backend/proto";
import { extent, histogram, quantile } from "d3-array";
import { scaleLinear, scaleSequential } from "d3-scale";
import { CardQueue } from "../cards";
import { HistogramData } from "./histogram-graph";
import { interpolateBlues } from "d3-scale-chromatic";
export interface IntervalGraphData {
intervals: number[];
}
export enum IntervalRange {
Month = 0,
Percentile50 = 1,
Percentile95 = 2,
Percentile999 = 3,
All = 4,
}
export function gatherIntervalData(data: pb.BackendProto.GraphsOut): IntervalGraphData {
const intervals = (data.cards as pb.BackendProto.Card[])
.filter((c) => c.queue == CardQueue.Review)
.map((c) => c.ivl);
return { intervals };
}
function hoverText(
data: HistogramData,
binIdx: number,
_cumulative: number,
percent: number
): string {
const bin = data.bins[binIdx];
const interval =
bin.x1! - bin.x0! === 1
? `${bin.x0} day interval`
: `${bin.x0}~${bin.x1} day interval`;
return (
`${bin.length} cards with ${interval}. ` +
`<br>${percent.toFixed(1)}% cards at or before this point.`
);
}
export function prepareIntervalData(
data: IntervalGraphData,
range: IntervalRange
): HistogramData | null {
// get min/max
const allIntervals = data.intervals;
if (!allIntervals.length) {
return null;
}
const total = allIntervals.length;
const [xMin, origXMax] = extent(allIntervals);
let xMax = origXMax;
// cap max to selected range
switch (range) {
case IntervalRange.Month:
xMax = Math.min(xMax!, 31);
break;
case IntervalRange.Percentile50:
xMax = quantile(allIntervals, 0.5);
break;
case IntervalRange.Percentile95:
xMax = quantile(allIntervals, 0.95);
break;
case IntervalRange.Percentile999:
xMax = quantile(allIntervals, 0.999);
break;
case IntervalRange.All:
break;
}
xMax = xMax! + 1;
// cap bars to available range
const desiredBars = Math.min(70, xMax! - xMin!);
const scale = scaleLinear().domain([xMin!, xMax!]).nice();
const bins = histogram()
.domain(scale.domain() as any)
.thresholds(scale.ticks(desiredBars))(allIntervals);
// start slightly darker
const shiftedMin = xMin! - Math.round((xMax - xMin!) / 10);
const colourScale = scaleSequential(interpolateBlues).domain([shiftedMin, xMax]);
return { scale, bins, total, hoverText, colourScale, showArea: true };
}