Fix problem when zooming

sohstationviewer/view/plotting/plotting_widget/plotting_widget.py

@@ -484,7 +484,7 @@ class PlottingWidget(QtWidgets.QScrollArea):
                     # channel not plotted
                     continue
                 c_data = self.plotting_data1[chan_id]
-                self.get_zoom_data(c_data, chan_id)
+                self.get_zoom_data(c_data, chan_id, self.plotting_data1)
             for chan_id in self.plotting_data2:
                 c_data = self.plotting_data2[chan_id]
                 self.get_zoom_data(c_data, chan_id)
@@ -511,6 +511,10 @@ class PlottingWidget(QtWidgets.QScrollArea):
                 new_min_y = None
                 new_max_y = None
                 if hasattr(ax, 'x_list'):
+                    if not hasattr(ax, 'y_list'):
+                        # dotForTime plots have attribute 'x_list' but not
+                        # 'y_list'
+                        continue
                     total_points = 0
                     tr_min_ys = []
                     tr_max_ys = []