Create a min state item

bliss/flint/model/plot_state_model.py

@@ -314,3 +314,77 @@ class MaxCurveItem(plot_model.AbstractIncrementalComputableItem, CurveStatisticM
             max_index, max_location_y, max_location_x, min_y_value, nb + len(xx)
         )
         return result
+
+
+class MinData(NamedTuple):
+    min_index: int
+    min_location_y: float
+    min_location_x: float
+    max_y_value: float
+    nb_points: int
+
+
+class MinCurveItem(plot_model.AbstractIncrementalComputableItem, CurveStatisticMixIn):
+    """Statistic identifying the minimum location of a curve."""
+
+    def isResultValid(self, result):
+        return result is not None
+
+    def compute(self, scan: scan_model.Scan) -> Optional[MinData]:
+        sourceItem = self.source()
+
+        xx = sourceItem.xArray(scan)
+        yy = sourceItem.yArray(scan)
+        if xx is None or yy is None:
+            return None
+
+        min_index = numpy.argmin(yy)
+        max_y_value = numpy.max(yy)
+        min_location_x, min_location_y = xx[min_index], yy[min_index]
+
+        result = MinData(
+            min_index, min_location_y, min_location_x, max_y_value, len(xx)
+        )
+        return result
+
+    def incrementalCompute(
+        self, previousResult: MinData, scan: scan_model.Scan
+    ) -> MinData:
+        sourceItem = self.source()
+
+        xx = sourceItem.xArray(scan)
+        yy = sourceItem.yArray(scan)
+        if xx is None or yy is None:
+            raise ValueError("Non empty data is expected")
+
+        nb = previousResult.nb_points
+        if nb == len(xx):
+            # obviously nothing to compute
+            return previousResult
+
+        xx = xx[nb:]
+        yy = yy[nb:]
+
+        min_index = numpy.argmin(yy)
+        max_y_value = numpy.max(yy)
+        min_location_x, min_location_y = xx[min_index], yy[min_index]
+        min_index = min_index + nb
+
+        if previousResult.max_y_value < max_y_value:
+            max_y_value = previousResult.max_y_value
+
+        if previousResult.min_location_y < min_location_y:
+            # Update and return the previous result
+            return MinData(
+                previousResult.min_index,
+                previousResult.min_location_y,
+                previousResult.min_location_x,
+                max_y_value,
+                nb + len(xx),
+            )
+
+        # Update and new return the previous result
+        result = MinData(
+            min_index, min_location_y, min_location_x, max_y_value, nb + len(xx)
+        )
+        return result

tests/flint/model/test_plot_state_model.py

@@ -41,6 +41,23 @@ def test_max_compute():
     assert result.min_y_value == -10
 
 
+def test_min_compute():
+    scan = None
+    yy = [0, -10, 2, 5, 9, 500, 100]
+    xx = numpy.arange(len(yy)) * 10
+
+    item = plot_state_model.MinCurveItem()
+    curveItem = CurveMock(xx=xx, yy=yy)
+    item.setSource(curveItem)
+
+    result = item.compute(scan)
+    assert result.nb_points == len(xx)
+    assert result.min_index == 1
+    assert result.min_location_x == 10
+    assert result.min_location_y == -10
+    assert result.max_y_value == 500
+
+
 def test_max_incremental_compute_1():
     """The result is part of the increment"""
     scan = None