Update scale factor and offset [viirs_l1b]

satpy/readers/viirs_l1b.py

@@ -235,6 +235,11 @@ def get_dataset(self, dataset_id, ds_info):
         if factors[0] != 1 or factors[1] != 0:
             data *= factors[0]
             data += factors[1]
+
+        # update scale_factor and scale_offset
+        data.attrs["scale_factor"] = scale_factor
+        data.attrs["add_offset"] = scale_offset
+
         # rename dimensions to correspond to satpy's 'y' and 'x' standard
         if "number_of_lines" in data.dims:
             data = data.rename({"number_of_lines": "y", "number_of_pixels": "x"})