[update] small changes increasing code robustness

PyLoT.py

@@ -3590,7 +3590,7 @@ class MainWindow(QMainWindow):
     def calc_magnitude(self):
         self.init_metadata()
         if not self.metadata:
-            return None
+            return []
 
         wf_copy = self.get_data().getWFData().copy()
 
@@ -3599,6 +3599,10 @@ class MainWindow(QMainWindow):
         for station in np.unique(list(self.getPicks('manual').keys()) + list(self.getPicks('auto').keys())):
             wf_select += wf_copy.select(station=station)
 
+        if not wf_select:
+            logging.warning('Empty Stream in calc_magnitude. Return.')
+            return []
+
         corr_wf = restitute_data(wf_select, self.metadata)
         # calculate moment magnitude
         moment_mag = MomentMagnitude(corr_wf, self.get_data().get_evt_data(), self.inputs.get('vp'),

pylot/core/util/dataprocessing.py

@@ -654,6 +654,8 @@ def restitute_data(data, metadata, unit='VEL', force=False, ncores=0):
     """
 
     # data = remove_underscores(data)
+    if not data:
+        return
 
     # loop over traces
     input_tuples = []
@@ -661,9 +663,14 @@ def restitute_data(data, metadata, unit='VEL', force=False, ncores=0):
         input_tuples.append((tr, metadata, unit, force))
         data.remove(tr)
 
-    pool = gen_Pool(ncores)
-    result = pool.imap_unordered(restitute_trace, input_tuples)
-    pool.close()
+    if ncores == 0:
+        result = []
+        for input_tuple in input_tuples:
+            result.append(restitute_trace(input_tuple))
+    else:
+        pool = gen_Pool(ncores)
+        result = pool.imap_unordered(restitute_trace, input_tuples)
+        pool.close()
 
     for tr, remove_trace in result:
         if not remove_trace: