Centroid subtracts dark image if there is one

src/toolbox_scs/detectors/hrixs.py

@@ -333,11 +333,11 @@ class hRIXS:
             # If runNB cannot be iterated over, we assume it's a single run
             data = self.from_run(runNB, proposal)
         self.dark_image = data['hRIXS_det'].mean(dim='trainId')
+        self.dark_im_array = self.dark_image.to_numpy()
         self.USE_DARK = True
 
     def find_curvature(self, runNB, proposal=None, plot=True, args=None, **kwargs):
         data = self.from_run(runNB, proposal)
-
         image = data['hRIXS_det'].sum(dim='trainId') \
                 .to_numpy()[self.X_RANGE, self.Y_RANGE].T
         if args is None:
@@ -356,8 +356,12 @@ class hRIXS:
         hit_y = []
         ret = np.zeros((len(data["hRIXS_det"]), bins))
         for image, r in zip(data["hRIXS_det"], ret):
+            if self.USE_DARK:
+                use_image = image.to_numpy() - self.dark_im_array
+            else:
+                use_image = image.to_numpy()
             c = centroid(
-                image.to_numpy()[self.X_RANGE, self.Y_RANGE].T,
+                use_image[self.X_RANGE, self.Y_RANGE].T,
                 threshold=self.THRESHOLD,
                 std_threshold=self.STD_THRESHOLD,
                 curvature=(self.CURVE_A, self.CURVE_B))