fix: calibrateX if not enough peaks found

Author: lpatiny

src/filters/x/__tests__/calibrateX.test.ts

@@ -87,4 +87,44 @@ describe('calibrateX', () => {
       Float64Array.from([1, 1, 1, 1, 700, 1, 5, 1, 1, 1, 1, 1, 1]),
     );
   });
+
+  it('2 peaks', () => {
+    let data = {
+      x: Float64Array.from([
+        0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19,
+        20,
+      ]),
+      y: Float64Array.from([
+        1, 1, 1, 1, 1, 700, 1, 1, 1, 1, 1, 1, 1, 1, 1, 700, 1, 1, 1, 1, 1,
+      ]),
+    };
+
+    let gsdOptions = {
+      minMaxRatio: 0.4,
+      realTopDetection: true,
+      smoothY: true,
+      sgOptions: {
+        windowSize: 5,
+        polynomial: 3,
+      },
+    };
+
+    let shifted = calibrateX(data, {
+      targetX: 6,
+      gsd: gsdOptions,
+      nbPeaks: 2,
+    });
+    // because we look for the real maximum it is not exactly 2
+    expect(shifted.data.x).toMatchCloseTo(
+      Float64Array.from([
+        -4, -3, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
+        16,
+      ]),
+    );
+    expect(shifted.data.y).toStrictEqual(
+      Float64Array.from([
+        1, 1, 1, 1, 1, 700, 1, 1, 1, 1, 1, 1, 1, 1, 1, 700, 1, 1, 1, 1, 1,
+      ]),
+    );
+  });
 });

src/filters/x/calibrateX.ts

@@ -65,7 +65,7 @@ export function calibrateX(
     .sort((a, b) => b.y - a.y)
     .slice(0, nbPeaks);
 
-  if (peaks.length === 0) return { data };
+  if (peaks.length < nbPeaks) return { data };
 
   const middle = xMean(peaks.map((peak) => peak.x));
   return { data: { x: xAdd(data.x, targetX - middle), y: data.y } };