SYNC: Merge pull request #4 from dbgate/feature/charts

packages/datalib/src/chartScoring.ts

@@ -0,0 +1,23 @@
+import _sortBy from 'lodash/sortBy';
+import _sum from 'lodash/sum';
+import { ChartLimits, ChartYFieldDefinition, ProcessedChart } from './chartDefinitions';
+
+export function getChartScore(chart: ProcessedChart): number {
+  let res = 0;
+  res += chart.rowsAdded * 5;
+
+  const ydefScores = chart.definition.ydefs.map(yField => getChartYFieldScore(chart, yField));
+  const sorted = _sortBy(ydefScores).reverse();
+  res += _sum(sorted.slice(0, ChartLimits.AUTODETECT_MEASURES_LIMIT));
+  return res;
+}
+
+export function getChartYFieldScore(chart: ProcessedChart, yField: ChartYFieldDefinition): number {
+  let res = 0;
+  res += chart.validYRows[yField.field] * 5; // score for valid Y rows
+  res += (chart.topDistinctValues[yField.field]?.size ?? 0) * 20; // score for distinct values in Y field
+  res += chart.rowsAdded * 2; // base score for rows added
+  res -= (chart.invalidYRows[yField.field] ?? 0) * 50; // penalty for invalid Y rows
+
+  return res;
+}