Multi-thread TPS plot

Closes #2 (closed).

#30 (closed).17

sohstationviewer/view/plotting/time_power_squared_dialog.py

@@ -61,8 +61,11 @@ class TimePowerSquaredWidget(plotting_widget.PlottingWidget):
         self.tps_t = 0
 
         self.tps_processors: List[TimePowerSquaredProcessor] = []
+        # The list of all channels that are processed.
         self.channels = []
+        # The list of channels that have been processed.
         self.processed_channels = []
+
         # The post-processing step does not take too much time so there is no
         # need to limit the number of threads that can run at once.
         self.thread_pool = QtCore.QThreadPool()
@@ -83,10 +86,6 @@ class TimePowerSquaredWidget(plotting_widget.PlottingWidget):
         :param waveform_data: dict - read waveform data of selected data set,
             refer to DataTypeModel.__init__.waveform_data[key]['read_data']
         """
-        if self.axes:
-            self.plotting_axes.fig.clear()
-            self.draw()
-
         self.processed_channels = []
         self.channels = []
         self.tps_processors = []
@@ -99,6 +98,7 @@ class TimePowerSquaredWidget(plotting_widget.PlottingWidget):
 
         if self.axes:
             self.plotting_axes.fig.clear()
+            self.draw()
         self.date_mode = self.parent.date_format.upper()
         if waveform_data is not None:
             self.plotting_data1 = waveform_data
@@ -120,7 +120,6 @@ class TimePowerSquaredWidget(plotting_widget.PlottingWidget):
         for chan_id in self.plotting_data1:
             c_data = self.plotting_data1[chan_id]
             if 'tps_data' not in c_data:
-                # get new minX, maxX according to exact start time  of days
                 self.channels.append(chan_id)
                 channel_processor = TimePowerSquaredProcessor(
                     chan_id, c_data, self.min_x, self.max_x,
@@ -140,7 +139,16 @@ class TimePowerSquaredWidget(plotting_widget.PlottingWidget):
             self.thread_pool.start(processor)
 
     @QtCore.Slot()
-    def channel_done(self, chan_id):
+    def channel_done(self, chan_id: str):
+        """
+        Called when a TPS processor finishes processing a channel. Plot the
+        channel's data if chan_id is not the empty string and add chan_id to
+        the list of processed channel. If all channels are processed, move to
+        final step.
+
+        :param chan_id: the name of the channel that were processed. Is the
+            empty string if processing is stopped prematurely.
+        """
         self.finished_lock.lock()
         if chan_id != '':
             ax = self.plot_channel(self.plotting_data1[chan_id], chan_id)
@@ -156,6 +164,7 @@ class TimePowerSquaredWidget(plotting_widget.PlottingWidget):
         self.finished_lock.unlock()
 
     def done(self):
+        """Add finishing touches to the plot and display it on the screen."""
         self.set_legend()
         # Set view size fit with the given data
         if self.main_widget.geometry().height() < self.plotting_bot_pixel:
@@ -417,6 +426,7 @@ class TimePowerSquaredWidget(plotting_widget.PlottingWidget):
             zm2.set_data(x_idx, y_idx)
 
     def request_stop(self):
+        """Request all running channel processors to stop."""
         for processor in self.tps_processors:
             processor.request_stop()