Merge pull request #19279 from snukhulov/feat-add-minmax-sampler

feat(sampler): add min-max sampler function
apache · Nov 27, 2023 · c5e0910 · c5e0910
2 parents b07ce79 + 4a63340
commit c5e0910
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Showing 3 changed files with 131 additions and 2 deletions.
diff --git a/src/processor/dataSample.ts b/src/processor/dataSample.ts
@@ -61,6 +61,22 @@ const samplers: Dictionary<Sampler> = {
         // NaN will cause illegal axis extent.
         return isFinite(min) ? min : NaN;
     },
+    minmax: function (frame) {
+        let turningPointAbsoluteValue = -Infinity;
+        let turningPointOriginalValue = -Infinity;
+
+        for (let i = 0; i < frame.length; i++) {
+            const originalValue = frame[i];
+            const absoluteValue = Math.abs(originalValue);
+
+            if (absoluteValue > turningPointAbsoluteValue) {
+                turningPointAbsoluteValue = absoluteValue;
+                turningPointOriginalValue = originalValue;
+            }
+        }
+
+        return isFinite(turningPointOriginalValue) ? turningPointOriginalValue : NaN;
+    },
     // TODO
     // Median
     nearest: function (frame) {
@@ -116,4 +132,4 @@ export default function dataSample(seriesType: string): StageHandler {
             }
         }
     };
-}
+}
diff --git a/src/util/types.ts b/src/util/types.ts
@@ -1675,7 +1675,7 @@ export interface SeriesStackOptionMixin {
 type SamplingFunc = (frame: ArrayLike<number>) => number;
 
 export interface SeriesSamplingOptionMixin {
-    sampling?: 'none' | 'average' | 'min' | 'max' | 'sum' | 'lttb' | SamplingFunc
+    sampling?: 'none' | 'average' | 'min' | 'max' | 'minmax' | 'sum' | 'lttb' | SamplingFunc
 }
 
 export interface SeriesEncodeOptionMixin {

diff --git a/test/line-sampling.html b/test/line-sampling.html