FIX: memory leak when calling add_data in loop

Author: Martin Luessi

surfer/viz.py

@@ -768,7 +768,7 @@ def add_data(self, array, min=None, max=None, thresh=None,
                  colormap="RdBu_r", alpha=1,
                  vertices=None, smoothing_steps=20, time=None,
                  time_label="time index=%d", colorbar=True,
-                 hemi=None):
+                 hemi=None, remove_existing=True):
         """Display data from a numpy array on the surface.
 
         This provides a similar interface to add_overlay, but it displays
@@ -817,6 +817,8 @@ def add_data(self, array, min=None, max=None, thresh=None,
             If None, it is assumed to belong to the hemipshere being
             shown. If two hemispheres are being shown, an error will
             be thrown.
+        remove_existing : bool
+            Remove surface added by previous "add_data" call.
         """
         hemi = self._check_hemi(hemi)
 
@@ -895,6 +897,11 @@ def add_data(self, array, min=None, max=None, thresh=None,
         data['surfaces'] = surfs
         data['colorbars'] = bars
         data['orig_ctable'] = ct
+
+        if remove_existing and self.data_dict[hemi] is not None:
+            for surf in self.data_dict[hemi]['surfaces']:
+                surf.parent.parent.remove()
+
         self.data_dict[hemi] = data
 
     def add_annotation(self, annot, borders=True, alpha=1, hemi=None,