clean up write_to_csv for MeasurmentResult (Fixs #30)

src/damaris/data/MeasurementResult.py

@@ -193,7 +193,7 @@ class MeasurementResult(Drawable.Drawable, collections.UserDict):
 
     def uses_statistics(self):
         """
-        drawable interface method, returns True
+        drawable interface method returns True
         """
         return True
 
@@ -203,10 +203,11 @@ class MeasurementResult(Drawable.Drawable, collections.UserDict):
         destination can be a file or a filename
         suitable for further processing
         """
-        # write sorted
         the_destination=destination
+        file_opened = False
         if type(destination) in (str,):
             the_destination=open(destination, "w")
+            file_opened = True
 
         the_destination.write("# quantity:"+str(self.quantity_name)+"\n")
         the_destination.write("# x y ysigma n\n")
@@ -222,7 +223,8 @@ class MeasurementResult(Drawable.Drawable, collections.UserDict):
                                                           y.mean_error(),
                                                           delimiter,
                                                           y.n))
-        the_destination=None
+        if file_opened:
+            the_destination.close()
 
 
     def write_to_hdf(self, hdffile, where, name, title, complib=None, complevel=None):