fix: sample func (#2004)

Co-authored-by: xuying.xu <[email protected]>
antvis · Oct 9, 2024 · 41045d2 · 41045d2
1 parent cd44a23
commit 41045d2
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Showing 3 changed files with 6 additions and 3 deletions.
diff --git a/packages/f2-algorithm/src/lttbDownSample.ts b/packages/f2-algorithm/src/lttbDownSample.ts
@@ -19,13 +19,13 @@ export default function lttbDownSample(data, options?: OptionsProps) {
   const len = data.length;
   const targetCount = len / rate;
 
-  if (rate >= len || targetCount === 0) {
+  if (rate >= len || targetCount < 2) {
     return data;
   }
 
   const sampled = [];
   let sampledIndex = 0;
-  // Bucket size
+  // Bucket size targetCount需大于2
   const bucketSize = Math.floor((len - 2) / (targetCount - 2));
 
   // A is the first point in the triangle

diff --git a/...lgorithm/test/__image_snapshots__/sample-test-tsx-sample-rate-小于可抽个数-1-snap.png b/...lgorithm/test/__image_snapshots__/sample-test-tsx-sample-rate-小于可抽个数-1-snap.png
diff --git a/packages/f2-algorithm/test/sample.test.tsx b/packages/f2-algorithm/test/sample.test.tsx
@@ -61,7 +61,7 @@ describe('sample', () => {
     expect(context).toMatchImageSnapshot();
   });
 
-  it('rate 小于 data个数', async () => {
+  it('rate 小于可抽个数', async () => {
     const res = await fetch(url);
     const result = [
       { value: { value: '0.516' }, updateTime: '2023-10-26T16:00:00.000Z', extInfo: null },
@@ -70,6 +70,9 @@ describe('sample', () => {
       { value: { value: '0.516' }, updateTime: '2023-10-29T16:00:00.000Z', extInfo: null },
       { value: { value: '0.472' }, updateTime: '2023-10-30T16:00:00.000Z', extInfo: null },
       { value: { value: '0.448' }, updateTime: '2023-10-31T16:00:00.000Z', extInfo: null },
+      { value: { value: '0.478' }, updateTime: '2023-10-32T16:00:00.000Z', extInfo: null },
+      { value: { value: '0.458' }, updateTime: '2023-10-33T16:00:00.000Z', extInfo: null },
+      { value: { value: '0.455' }, updateTime: '2023-10-34T16:00:00.000Z', extInfo: null },
     ];
     const data = result.map((d) => {
       return {