Index: fact/tools/pyscripts/pyfact/pyfact.py
===================================================================
--- fact/tools/pyscripts/pyfact/pyfact.py	(revision 14427)
+++ fact/tools/pyscripts/pyfact/pyfact.py	(revision 14428)
@@ -646,4 +646,6 @@
         # or whole arrays of numbers as well.
         # we treat single elements differently...
+        if number_of_elements == 0:
+            return 
         if number_of_elements == 1:
             # allocate some memory for a single number according to its type
@@ -690,6 +692,16 @@
             local = np.zeros( number_of_elements, nptype)
         
-        # Set the Pointer Address 
-        f.SetPtrAddress(colname, local)
+        # Set the Pointer Address
+        try:
+            f.SetPtrAddress(colname, local)
+        except TypeError:
+            print 'something was wrong with SetPtrAddress()'
+            print 'Type of colname', type(colname)
+            print 'colname:', colname
+            print 'Type of local', type(local)
+            print 'length of local', len(local)
+            print 'local should be alle zeros, since "local = np.zeros( number_of_elements, nptype)" '
+            raise
+            
         self._table_cols[colname] = local
         if number_of_elements > 1: